### Re: Measuring a system in a superposition of states vs in a mixed state

On Wed, Oct 31, 2018 at 7:30 AM Bruno Marchal wrote: > > On 30 Oct 2018, at 14:21, agrayson2...@gmail.com wrote: > > > > On Tuesday, October 30, 2018 at 8:58:30 AM UTC, Bruno Marchal wrote: >> >> >> On 29 Oct 2018, at 13:55, agrays...@gmail.com wrote: >> >> >> >> On Monday, October 29, 2018 at 10:22:02 AM UTC, Bruno Marchal wrote: >>> >>> >>> On 28 Oct 2018, at 13:21, agrays...@gmail.com wrote: >>> >>> >>> >>> On Sunday, October 28, 2018 at 9:27:56 AM UTC, Bruno Marchal wrote: On 25 Oct 2018, at 17:12, agrays...@gmail.com wrote: On Tuesday, October 23, 2018 at 10:39:11 PM UTC, agrays...@gmail.com wrote: > > If a system is in a superposition of states, whatever value measured, > will be repeated if the same system is repeatedly measured. But what > happens if the system is in a mixed state? TIA, AG > If you think about it, whatever value you get on a single trial for a mixed state, repeated on the same system, will result in the same value measured repeatedly. If this is true, how does measurement distinguish superposition of states, with mixed states? AG That is not correct. You can distinguish a mixture of particles in the up or down states with a set of 1/sqrt(2)(up+down) by measuring them with the {1/sqrt(2)(up+down), 1/sqrt(2)(up-down}) discriminating apparatus. With the mixture, half the particles will be defected in one direction, with the pure state, they will all pass in the same direction. Superposition would not have been discovered if that was not the case. >>> >>> >>> *And someone will supply the apparatus measuring (up + down), and (up - >>> down)? No such apparatuses are possible since those states are inherently >>> contradictory. We can only measure up / down. AG* >>> >>> >>> You can do the experience by yourself using a simple crystal of calcium >>> (CaCO3, Island Spath), or with polarising glass. Or with Stern-Gerlach >>> devices and electron spin. Just rotating (90° or 180°) an app/down >>> apparatus, gives you an (up + down)/(up - down) apparatus. >>> >> >> *I don't understand. With SG one can change the up/down axis by rotation, >> but that doesn't result in an (up + down), or (up - down) measurement. If >> that were the case, what is the operator for which those states are >> eigenstates? Which book by Albert? AG * >> >> >> David Z Albert, Quantum Mechanics and Experience, Harvard University >> Press, 1992. >> >> https://www.amazon.com/Quantum-Mechanics-Experience-David-Albert/dp/0674741137 >> >> Another very good books is >> >> D’Espagnat B. Conceptual foundations of Quantum mechanics, I see there >> is a new edition here: >> >> https://www.amazon.com/Conceptual-Foundations-Quantum-Mechanics-Advanced/dp/0738201049/ref=sr_1_1?s=books=UTF8=1540889778=1-1=d%27espagnat+conceptual+foundation+of+quantum+mechanics=41NcluHD6fL=_SY291_BO1,204,203,200_QL40_=srch >> >> It explains very well the difference between mixtures and pure states. >> >> Bruno >> > > *Thanks for the references. I think I have a reasonable decent > understanding of mixed states. Say a system is in a mixed state of phi1 and > phi2 with some probability for each. IIUC, a measurement will always result > in an eigenstate of either phi1 or phi2 (with relative probabilities > applying). * > > > If the measurement is done with a phi1/phi2 discriminating apparatus. Keep > in mind that any state can be seen as a superposition of other oblique or > orthogonal states. > I don't know if you're restricting the definition of phi1 and phi2 to some particular type of eigenstate or not, but in general aren't there pure states that are not eigenstates of any physically possible measurement apparatus, so there is no way to directly measure that a system is in such a state? -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Mon, May 2, 2016 at 1:10 AM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 2/05/2016 1:31 pm, Jesse Mazer wrote: > > On Sun, May 1, 2016 at 8:49 PM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> On 2/05/2016 7:52 am, Jesse Mazer wrote: >> >> On Fri, Apr 29, 2016 at 8:32 PM, Bruce Kellett < >> <bhkell...@optusnet.com.au>bhkell...@optusnet.com.au> wrote: >> >>> That is a semantic matter. There is a problem if one insists that >>> "non-local" means the propagation of a real physical influence (particle of >>> wave) faster-than-light. But "non-locality" in standard quantum usage means >>> the above -- the entangled state acts as a single physical unit even when >>> its components are widely separated. >> >> >> >> I agree it's a semantic matter, but your description of the "standard >> quantum usage" doesn't seem to be accurate. Among physicists, the standard >> understanding of "local" and "non-local" in the context of Bell's theorem >> and relativity is the one I cited earlier--a theory is "local" if and only >> if the function that gives you the value of local variables at any given >> point P in spacetime (or gives the best possible probabilistic prediction >> about their values, in the case of a non-deterministic theory) only >> requires as input the values of local variables at other points that lie >> within P's past light cone, whereas a "non-local" theory would be one where >> the function requires knowledge of variables at a spacelike separation from >> P to generate the best possible prediction. As I mentioned, I think this is >> explained most clearly in Bell's paper "La nouvelle cuisine" which you can >> find in the collection "Speakable and Unspeakable in Quantum Mechanics", >> and you can also find it discussed in other sources, >> http://arxiv.org/abs/0707.0401 for example. As for "acts as a single >> physical unit", that seems like a decidedly non-mathematical definition >> which physicists would steer clear of, unless you can provide a >> mathematical formalization or what you mean, or cite a mainstream source >> that provides one. >> >> >> I don't see any paper of the title you mention in my copy of "Speakable >> and Unspeakable in Quantum Mechanics", could you give a page number >> reference? >> > > > It's on p. 232 of the 2nd edition, chapter 24. > > > I have now looked at the paper by Norsen. It seems that the more detailed > definiton of locality does little more than remove the notion of > "superdeterminism" from the equation -- the idea that things in the common > past of A and B could conspire to give rise to the correlations. > The paper by Norsen at http://arxiv.org/pdf/0707.0401v3.pdf does mention the issue of ruling out superdeterminism, but that wasn't what I was referring to when I talked about the definition in La nouvelle cuisine which is repeated in Norsen's paper. Rather I was talking about equation 1 on page 4 whose physical meaning in terms of past light cones is show in Fig. 2 on the same page. Referring to the diagram and equation, b1 refers to the physical state of local variables in region 1, b2 refers to the physical state of local variables in another region 2 at a spacelike separation of 1, and B3 refers to some sufficiently detailed set of local states in region 3 which is in the past light cone of region 1, but entirely outside the past light cone of region 2. The idea is that by picking a sufficiently detailed set for your B3, you can have it so that once you know B3, additional knowledge of b2 is irrelevant to your prediction of what's going on in b1, i.e. you don't need anything outside the past light cone of 1 to make the best possible physical prediction about the physical facts in that region. So, nothing to do with superdeterminism, just a more formal statement of the idea I described earlier about the function for making predictions about a given region depending only on facts in the past light cone of that region. Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Mon, May 2, 2016 at 12:13 AM, Bruce Kellettwrote: > > No, I disagree. The setting *b* has no effect on what happens at a remote > location is sufficiently precise to encapsulate exactly what physicists > mean by locality. In quantum field theory, this is generalized to the > notion of local causality, which is the statement that the commutators of > all spacelike separate variables vanish -- as you mention below. > And if you used full quantum description of the measuring apparatus and experimenter, and didn't assume any collapse on measurement, then there would in general be no single "setting b" in the region of spacetime where one experimenter was choosing a setting, but rather a superposition of different settings. Do you think your preferred definition can be meaningfully applied to this case, and if so how? > > My qualitative definition of non-locality is not non-standard -- it is the >> definition frequently used by Bell, and (almost) everyone else. Your >> definition seems to want to take account of some sort of hidden variables, >> such that the quantum state as written does not contain all the information >> about that state. >> > > > There are no hidden variables in the MWI (though the definition of > locality should be general enough to cover theories with hidden variables > as well as ones with no hidden variables, since Bell's theorem is meant to > rule out local realist theories of either type). The "quantum state as > written" does not give any definite outcomes of measurements, only a set of > amplitudes on different eigenvectors associated with particular > eigenvalues, which are understood as possible measurement results. > > > True, but not relevant for these purposes. I am not ruling out an > Everettian interpretation of the state vector -- my definition of locality > simply rules out faster than light (FTL) transfer of information. Given the > standard quantum treatment of the entangled singlet state, non-locality is > unavoidable. > Without any assumption of "collapse", the *amplitudes* assigned to local measurements on either member of an entangled pair could be determined solely from amplitudes on locally-measurable variables in the past light cone--do you disagree? > That does not mean that there is actually a physical transfer of particles > or waves FTL, it simply means that the state is a unity, and changing one > part changes the whole state. That is the nature of quantum non-locality -- > it does not have a local explanation, even a FTL explanation. > There are no non-mathematical "explanations" for anything whatsoever in physics (obviously there can be explanations in words, but these are understood as shorthand for arguments that could be formalized mathematically). And in terms of mathematical physics, the "explanation" for a local physical fact about what's happening in one point in spacetime is just the mathematical function representing the "laws of physics" along with whatever initial boundary conditions have to be fed into the function to generate the prediction about that local physical fact. If the boundary conditions are all confined to the past light cone, I would say there is nothing FTL in this mathematical explanation--you may disagree, but so far you have been unable to provide any alternate precisely-defined conditions for distinguishing locality from non-locality, ones which we could still obviously make sense of even if we didn't assume a unique real-valued measurement setting and measurement outcome. > And if you just want the amplitudes for locally-measurable quantities in a > given region of spacetime, in quantum field theory my understanding is that > you can determine this using only knowledge of amplitudes for > locally-measurable quantities in the past light cone of that region (I > don't understand the details, but this is supposed to have to do with the > fact that the commutators for spacelike-separated points always vanish). > Only if you assume there is an objective "collapse" of the wavefunction at > the point of measurement does the quantum formalism become incompatible > with locality in the light cone sense. > > > That is not correct. You have not given a local account in MWI either. > What does "account" mean? A mathematical description, or a conceptual explanation in the English language? > Your "light cone sense" of locality would only add something to the > traditional sense if the quantum state were not a complete description of > the system. In other words, a hidden variable theory. > I have no idea why you think this, and you haven't made any argument for it. Your traditional sense seems to be simply ill-defined if we assume a superposition of different detecter settings in a single location in spacetime, and a superposition of measurement results at another location, whereas the "light-cone sense" is still well-defined here since it can cover local variables of any kind, including a

### Re: Non-locality and MWI

On Sun, May 1, 2016 at 8:49 PM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 2/05/2016 7:52 am, Jesse Mazer wrote: > > On Fri, Apr 29, 2016 at 8:32 PM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> That is a semantic matter. There is a problem if one insists that >> "non-local" means the propagation of a real physical influence (particle of >> wave) faster-than-light. But "non-locality" in standard quantum usage means >> the above -- the entangled state acts as a single physical unit even when >> its components are widely separated. > > > > I agree it's a semantic matter, but your description of the "standard > quantum usage" doesn't seem to be accurate. Among physicists, the standard > understanding of "local" and "non-local" in the context of Bell's theorem > and relativity is the one I cited earlier--a theory is "local" if and only > if the function that gives you the value of local variables at any given > point P in spacetime (or gives the best possible probabilistic prediction > about their values, in the case of a non-deterministic theory) only > requires as input the values of local variables at other points that lie > within P's past light cone, whereas a "non-local" theory would be one where > the function requires knowledge of variables at a spacelike separation from > P to generate the best possible prediction. As I mentioned, I think this is > explained most clearly in Bell's paper "La nouvelle cuisine" which you can > find in the collection "Speakable and Unspeakable in Quantum Mechanics", > and you can also find it discussed in other sources, > http://arxiv.org/abs/0707.0401 for example. As for "acts as a single > physical unit", that seems like a decidedly non-mathematical definition > which physicists would steer clear of, unless you can provide a > mathematical formalization or what you mean, or cite a mainstream source > that provides one. > > > I don't see any paper of the title you mention in my copy of "Speakable > and Unspeakable in Quantum Mechanics", could you give a page number > reference? > It's on p. 232 of the 2nd edition, chapter 24. > What I did find was chapter 8, "Locality in quantum mechanics: reply to > critics" (pp. 63-66). In that chapter, Bell says: "...now we add the > hypothesis of l*ocality*, that the setting *b* of a particular instrument > has no effect on what happens, A, in a remote region, and likewise that > *a* has no effect on B. With these *local* forms, it is *not *possible > to find functions A and B and a probability distribution *rho* which give > the correlations = -*a.b*." > > This is an informal statement of exactly the notion of locality or > non-locality that I have been using all along. Your more convoluted > statement may bear some relation to Bell's theory of local beables (chapter > 7 of his book), but the complications are unnecessary -- the informal > definition is the one most physicists would use in practice. > I disagree, physicists generally only use informal definitions if it's obvious they could be formalized, or if they are *implied* by some more precise technical definition (the looser definition you mention above would be implied by the more precise one I mentioned, *if* one assumes there is a unique truth about the setting at b and the measurement A). > My qualitative definition of non-locality is not non-standard -- it is the > definition frequently used by Bell, and (almost) everyone else. Your > definition seems to want to take account of some sort of hidden variables, > such that the quantum state as written does not contain all the information > about that state. > There are no hidden variables in the MWI (though the definition of locality should be general enough to cover theories with hidden variables as well as ones with no hidden variables, since Bell's theorem is meant to rule out local realist theories of either type). The "quantum state as written" does not give any definite outcomes of measurements, only a set of amplitudes on different eigenvectors associated with particular eigenvalues, which are understood as possible measurement results. And if you just want the amplitudes for locally-measurable quantities in a given region of spacetime, in quantum field theory my understanding is that you can determine this using only knowledge of amplitudes for locally-measurable quantities in the past light cone of that region (I don't understand the details, but this is supposed to have to do with the fact that the commutators for spacelike-separated points always vanish). Only if you assume there is an objective "collapse" of

### Re: Non-locality and MWI

On Fri, Apr 29, 2016 at 8:32 PM, Bruce Kellettwrote: > > That is a semantic matter. There is a problem if one insists that > "non-local" means the propagation of a real physical influence (particle of > wave) faster-than-light. But "non-locality" in standard quantum usage means > the above -- the entangled state acts as a single physical unit even when > its components are widely separated. I agree it's a semantic matter, but your description of the "standard quantum usage" doesn't seem to be accurate. Among physicists, the standard understanding of "local" and "non-local" in the context of Bell's theorem and relativity is the one I cited earlier--a theory is "local" if and only if the function that gives you the value of local variables at any given point P in spacetime (or gives the best possible probabilistic prediction about their values, in the case of a non-deterministic theory) only requires as input the values of local variables at other points that lie within P's past light cone, whereas a "non-local" theory would be one where the function requires knowledge of variables at a spacelike separation from P to generate the best possible prediction. As I mentioned, I think this is explained most clearly in Bell's paper "La nouvelle cuisine" which you can find in the collection "Speakable and Unspeakable in Quantum Mechanics", and you can also find it discussed in other sources, http://arxiv.org/abs/0707.0401 for example. As for "acts as a single physical unit", that seems like a decidedly non-mathematical definition which physicists would steer clear of, unless you can provide a mathematical formalization or what you mean, or cite a mainstream source that provides one. Bruno should be aware that in the discussion you and I had earlier, you used this sort of qualitative non-standard definition to argue even if the function giving values of physical variables at each point *does* depend solely on data from the past light cone, that is "irrelevant" to deciding whether the theory is "local" in your sense, presumably because you think there can be qualitative features of the function itself that can make it "non-local" for reasons unrelated to the question of what data the function takes as input. Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Wed, Apr 27, 2016 at 2:35 AM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 27/04/2016 4:13 pm, Jesse Mazer wrote: > > On Wed, Apr 27, 2016 at 1:40 AM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> On 27/04/2016 3:22 pm, Jesse Mazer wrote: >> >> On Wed, Apr 27, 2016 at 12:47 AM, Bruce Kellett < >> <bhkell...@optusnet.com.au>bhkell...@optusnet.com.au> wrote: >> >>> Your simulation assumes the quantum mechanical results. In other words, >>> it assumes non-locality in order to calculate the statistics. Where does >>> the cos^2(theta/2) come from in your analysis? >>> >> >> The question I asked you was whether you thought you could definitively >> disprove the idea that all the observable statistics of QM could be >> reproduced by rules that are "local" in the specific narrow sense I had >> described to you--remember all that stuff about having computers >> determining what the value of local variables at each point in spacetime >> should be, using only information about the value of local variables in the >> past light cone of that point, plus the general rules programmed into them >> (which take that information about the past light cone as input, and spit >> out the value of local variables at that point as output)? This is a narrow >> and mathematically well-defined question (and is based specifically on how >> Bell defined 'locality'), it's completely irrelevant to the question >> whether or not the *idea* for the rules that I programmed into the >> computers that perform these local calculations came from looking at some >> equations that are written in a 'non-local' way (i.e., the equations >> generate their predictions by evolving a single 'state vector' for the >> entire spatially-distributed system). Do you understand this distinction >> between the narrow, well-defined definition of "local rules" (if you're >> unclear on what I mean here, please ask), and broader questions about what >> inspired the rules themselves? And are you claiming that even if we >> restrict our attention to the narrow definition of "local rules", you can >> still say with 100% certainty that no such "local rules" can accurately >> reproduce all the predictions about measurement outcomes made by QM? >> >> >> Your question, as outlined above, is completely devoid of interest to me >> as a physicist. I am interested in physical models that give an insight >> into how things come about. >> >> And yes, I am 100% certain that local rules, with local models for >> deciding what statistics should be reproduced to mimic quantum results on >> entangled systems, are impossible. >> > > And are you 100% certain of that last statement even if we define "local > rules" in the specific narrow sense I have described? Your comment that my > question concerning this narrow definition of locality is 'devoid of > interest' to you makes it unclear whether you were actually willing to > stick to the narrow definition in addressing my question, as I had > requested. > > > It is of no interest. You, and Rubin, advertised your work as a local > explanation of the EPR statistics. On detailed examination and pressing, > you admit that this is not the case > No, we use a definition of "locality" where it *is* the case, a mathematical definition that seems to correspond to how pretty much all mainstream physicists use the term "locality". You seem to say that even if a function takes as input only variables from the past light cone of a region to generate predictions about the values of variables within that region, it can be non-local because of something to do with where the idea for the function itself came from, a fuzzy notion that doesn't seem like it's likely to have any clear mathematical definition (if you think it can, please provide a general set of mathematical criteria for deciding whether some arbitrary mathematical function for generating predictions from boundary conditions is 'local', such that even a function that only uses variables in the past light cone as input may still fail to qualify as local). And since you answer my direct request to address my question with "it is of no interest", should I presume you are just refusing to answer the question I asked? Generally when people refuse to answer straightforward questions I take that as a sign they are not really interested in making a good-faith effort at mutual understanding, on figuring out what points we can (grudgingly) agree on as well as where we disagree (as opposed to just making a rhetorical case for a preferred view, or against a disli

### Re: Non-locality and MWI

On Wed, Apr 27, 2016 at 1:50 AM, Brent Meeker <meeke...@verizon.net> wrote: > > > On 4/26/2016 10:29 PM, Jesse Mazer wrote: > > > > On Tue, Apr 26, 2016 at 11:51 PM, Brent Meeker <meeke...@verizon.net> > wrote: > >> >> >> On 4/26/2016 8:38 PM, Jesse Mazer wrote: >> >>> OK, let's say experimenter A measures particle 1, and experimenter B >>> measures particle 2. Any given copy of particle 1 has a "label" that says >>> something about the state of 2--we can imagine that the copy of particle 1 >>> carries a little clipboard on which is written down both its own quantum >>> state, and a quantum state it assigns to particle 2. When that copy of 1 is >>> measured, it not only adjusts its own state (to an eigenstate of the >>> measurement operator), it also adjusts the state it has written down for 2. >>> You seem to be assuming, in effect, that when a copy of 1 adjusts what it >>> has written down for the state of 2 on its own clipboard, this must mean >>> that copies of 2 also instantaneously adjust what they have written down >>> about *their* own state. However, in a copying-with-matching scheme, >>> there's no reason this need be the case! >>> >> >> That's pretty much the many-universes model that Bruno proposes. But it's >> non-local in the sense that the "matching scheme" must take account of >> which measurements are compatible, i.e. it "knows" the results even while >> they are spacelike separated. >> > > Why do you say that? Do you understand that in the type of scheme I am > talking about (and Mark Rubin too, I think), no "matching" between copies > of measurement-outcomes at different locations takes place at any location > in spacetime that doesn't lie in the future light cone of both measurements? > > > I think I understand it. Consider a spacelike slice that contains the > earliest overlap of the A and B measurment events forward lightcones. On > this slice the proper correlated results must obtain, which means that > observers at opposite sides of the lightcones from the overlap must also > observe the proper correlation - even though they are spacelike relative to > the overlap and spacelike relative to one of the measurement events. > I think you're misunderstanding--if we imagine a cellular-automata-like implementation where we have separate computers calculating the state of each small region of space, it's not as if a mapping calculated by a computer at one point in a spacelike slice needs to be instantaneously transmitted to all the other computers in that same spacelike slice. Correlations don't need to obtain across entire spacelike slices, information about mappings is itself local information associated with particular copies of localized systems (like copies of an experimenter that has received signals about two different measurements--each copy of this experimenter has a state that is determined by the outcome of both measurements, and hence qualifies as a physical 'mapping' between particular copies of the measurements themselves) Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Wed, Apr 27, 2016 at 1:40 AM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 27/04/2016 3:22 pm, Jesse Mazer wrote: > > On Wed, Apr 27, 2016 at 12:47 AM, Bruce Kellett <bhkell...@optusnet.com.au > > wrote: > >> Your simulation assumes the quantum mechanical results. In other words, >> it assumes non-locality in order to calculate the statistics. Where does >> the cos^2(theta/2) come from in your analysis? >> > > The question I asked you was whether you thought you could definitively > disprove the idea that all the observable statistics of QM could be > reproduced by rules that are "local" in the specific narrow sense I had > described to you--remember all that stuff about having computers > determining what the value of local variables at each point in spacetime > should be, using only information about the value of local variables in the > past light cone of that point, plus the general rules programmed into them > (which take that information about the past light cone as input, and spit > out the value of local variables at that point as output)? This is a narrow > and mathematically well-defined question (and is based specifically on how > Bell defined 'locality'), it's completely irrelevant to the question > whether or not the *idea* for the rules that I programmed into the > computers that perform these local calculations came from looking at some > equations that are written in a 'non-local' way (i.e., the equations > generate their predictions by evolving a single 'state vector' for the > entire spatially-distributed system). Do you understand this distinction > between the narrow, well-defined definition of "local rules" (if you're > unclear on what I mean here, please ask), and broader questions about what > inspired the rules themselves? And are you claiming that even if we > restrict our attention to the narrow definition of "local rules", you can > still say with 100% certainty that no such "local rules" can accurately > reproduce all the predictions about measurement outcomes made by QM? > > > Your question, as outlined above, is completely devoid of interest to me > as a physicist. I am interested in physical models that give an insight > into how things come about. > > And yes, I am 100% certain that local rules, with local models for > deciding what statistics should be reproduced to mimic quantum results on > entangled systems, are impossible. > And are you 100% certain of that last statement even if we define "local rules" in the specific narrow sense I have described? Your comment that my question concerning this narrow definition of locality is 'devoid of interest' to you makes it unclear whether you were actually willing to stick to the narrow definition in addressing my question, as I had requested. To try to restate this "specific narrow sense" one more time, note that at the broadest level, any dynamical "law of physics" is a mathematical function that takes some boundary conditions as input, and generates a prediction about some other physical state as output--for example, for Newtonian gravity the inputs could be the positions, velocities and masses of some objects at time T1, and the output could be their positions and velocities at some later time T2. So "local" in the specific narrow sense I'm using is a condition that ONLY deals with what inputs are necessary to generate outputs, and has NOTHING to do with the function itself. If the function takes as input boundary conditions that are restricted to the past light cone of some region of spacetime R, and as output tells you the values of local physical variables in that region R, and it can do this for *any* region of spacetime R where you want to predict the local variables, then this automatically qualifies the laws of physics as "local" according to the narrow sense I am using (which again matches how Bell used it, if you have doubts about this check out his paper 'La nouvelle cuisine' which can be found in the collection 'Speakable and Unspeakable in Quantum Mechanics'). Hopefully this definition is clear, even if you find it uninteresting. > Rules that deal with non-locally produced statistical distributions can do > anything you want -- vide my urn model -- they simply have nothing to do > with physics, can teach us nothing about physics. > Your urn model does not qualify as "local" in my narrow sense above, in the sense that it only made predictions about joint results, but didn't generate predictions about the results of each experimenter's measurement in the region of spacetime where they performed the measurement, using only information about physical variables in the past light cone of that region (where the other experimenter's choic

### Re: Non-locality and MWI

On Tue, Apr 26, 2016 at 11:51 PM, Brent Meeker <meeke...@verizon.net> wrote: > > > On 4/26/2016 8:38 PM, Jesse Mazer wrote: > >> OK, let's say experimenter A measures particle 1, and experimenter B >> measures particle 2. Any given copy of particle 1 has a "label" that says >> something about the state of 2--we can imagine that the copy of particle 1 >> carries a little clipboard on which is written down both its own quantum >> state, and a quantum state it assigns to particle 2. When that copy of 1 is >> measured, it not only adjusts its own state (to an eigenstate of the >> measurement operator), it also adjusts the state it has written down for 2. >> You seem to be assuming, in effect, that when a copy of 1 adjusts what it >> has written down for the state of 2 on its own clipboard, this must mean >> that copies of 2 also instantaneously adjust what they have written down >> about *their* own state. However, in a copying-with-matching scheme, >> there's no reason this need be the case! >> > > That's pretty much the many-universes model that Bruno proposes. But it's > non-local in the sense that the "matching scheme" must take account of > which measurements are compatible, i.e. it "knows" the results even while > they are spacelike separated. > Why do you say that? Do you understand that in the type of scheme I am talking about (and Mark Rubin too, I think), no "matching" between copies of measurement-outcomes at different locations takes place at any location in spacetime that doesn't lie in the future light cone of both measurements? Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Wed, Apr 27, 2016 at 12:47 AM, Bruce Kellettwrote: > Your simulation assumes the quantum mechanical results. In other words, it > assumes non-locality in order to calculate the statistics. Where does the > cos^2(theta/2) come from in your analysis? > The question I asked you was whether you thought you could definitively disprove the idea that all the observable statistics of QM could be reproduced by rules that are "local" in the specific narrow sense I had described to you--remember all that stuff about having computers determining what the value of local variables at each point in spacetime should be, using only information about the value of local variables in the past light cone of that point, plus the general rules programmed into them (which take that information about the past light cone as input, and spit out the value of local variables at that point as output)? This is a narrow and mathematically well-defined question (and is based specifically on how Bell defined 'locality'), it's completely irrelevant to the question whether or not the *idea* for the rules that I programmed into the computers that perform these local calculations came from looking at some equations that are written in a 'non-local' way (i.e., the equations generate their predictions by evolving a single 'state vector' for the entire spatially-distributed system). Do you understand this distinction between the narrow, well-defined definition of "local rules" (if you're unclear on what I mean here, please ask), and broader questions about what inspired the rules themselves? And are you claiming that even if we restrict our attention to the narrow definition of "local rules", you can still say with 100% certainty that no such "local rules" can accurately reproduce all the predictions about measurement outcomes made by QM? Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Tue, Apr 26, 2016 at 9:16 PM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 27/04/2016 1:13 am, Jesse Mazer wrote: > > On Tue, Apr 26, 2016 at 6:45 AM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> >> You think that "the state of the other particle" refers to the quantum >> state that would be assigned to B given only knowledge of the state of A >> (as well as knowledge of how they were entangled originally). Actually, >> that is the interpretation I gave the words, except I teased out what that >> actually meant. From the entangled state, given A's state (result, say >> |+>), you would assign a state |-> to B. But this is wrong for spacelike >> separations -- the state B actually measures is exactly the same as the >> state A measured: |psi> = (|+>|-> - |->|+>)/sqrt(2). >> > > You use the full state if you just want to generate the total > probabilities for various possible *joint* outcomes. But if you want a > conditional probability of various outcomes *just for B* given knowledge of > what measurement A got, this can be done in QM, in the Schroedinger picture > you could project |psi> onto on eigenstate that corresponds to whatever > definite outcome was measured on A, resulting in a different state vector > for the combined system |psi'> which may lead to different probabilities of > getting various results for B, but which does not assume any knowledge of > what measurement was actually performed on B. I assume something similar is > possible in the Heisenberg picture which Rubin is using, so I was > speculating that he meant something like this when he talked about a label > on one particle which says something about the state of the other particle. > > > I am well aware of this, and I also thought that was probably what Rubin > had in mind. The problem is that this simply sneaks non-locality in the > back door -- neither Rubin nor you appear to realize this. This is often > the problem I find with these attempts to give a local account of EPR -- > non-locality is built in unobtrusively! > > That is why I said that, in any strictly local account, if A gets |+>, B > still measures the original |psi>. The measurement by A cannot *locally* > affect the state that B measures (or vice versa). > OK, let's say experimenter A measures particle 1, and experimenter B measures particle 2. Any given copy of particle 1 has a "label" that says something about the state of 2--we can imagine that the copy of particle 1 carries a little clipboard on which is written down both its own quantum state, and a quantum state it assigns to particle 2. When that copy of 1 is measured, it not only adjusts its own state (to an eigenstate of the measurement operator), it also adjusts the state it has written down for 2. You seem to be assuming, in effect, that when a copy of 1 adjusts what it has written down for the state of 2 on its own clipboard, this must mean that copies of 2 also instantaneously adjust what they have written down about *their* own state. However, in a copying-with-matching scheme, there's no reason this need be the case! The state that particle 1 assigns to particle 2 on its clipboard may just be for the purposes of later matching--deciding which copy of 2 to "partner up with" once it can meet them (or get some type of causal influence from them). The fraction of copies of 2 that show a given result when B measure can still be totally independent of what the various copies of 1 have written down on their clipboards about the state *they* assign to 2. For example, say we are using a particular setup where if particle 1 is measured along a spatial vector V (say, one parallel to to the x-axis and pointing in the +x direction) and gives a result +, that means if particle 2 is measured at a 120-degree angle from V, it will have a 75% chance of giving the result + and a 25% chance of giving the result -. So if a given copy of particle 1 is indeed measured along V and does give a result +, it can adjust the state it assigns to particle 2 on its clipboard accordingly, assigning 2 a state (or reduced density matrix) which has an amplitude-squared of 0.75 for + at an orientation of 120 degrees from V. It can pass on this clipboard information (Rubin's 'label') to copies of other systems it interacts with, like the experimenter, who carry their own clipboards/labels. Then if that copy of the experimenter later interacts with particle 2 (or with some other particle or system that conveys information about particle 2), the state assigned to 2 on the experimenter's clipboard is used to decide which copy of particle 2 it should be matched with. In this case, this could ensure that if it gets matched to a copy of particle 2 that was indeed measured at an angle of 120 deg

### Re: Non-locality and MWI

On Tue, Apr 26, 2016 at 6:45 AM, Bruce Kellettwrote: > > > You think that "the state of the other particle" refers to the quantum > state that would be assigned to B given only knowledge of the state of A > (as well as knowledge of how they were entangled originally). Actually, > that is the interpretation I gave the words, except I teased out what that > actually meant. From the entangled state, given A's state (result, say > |+>), you would assign a state |-> to B. But this is wrong for spacelike > separations -- the state B actually measures is exactly the same as the > state A measured: |psi> = (|+>|-> - |->|+>)/sqrt(2). > You use the full state if you just want to generate the total probabilities for various possible *joint* outcomes. But if you want a conditional probability of various outcomes *just for B* given knowledge of what measurement A got, this can be done in QM, in the Schroedinger picture you could project |psi> onto on eigenstate that corresponds to whatever definite outcome was measured on A, resulting in a different state vector for the combined system |psi'> which may lead to different probabilities of getting various results for B, but which does not assume any knowledge of what measurement was actually performed on B. I assume something similar is possible in the Heisenberg picture which Rubin is using, so I was speculating that he meant something like this when he talked about a label on one particle which says something about the state of the other particle. There is also another possibility along the same lines, which is that for any entangled system in a pure state, you can construct a "reduced density matrix" for some subsystem, which gives the probabilities of various outcomes for measurements just on the subsystem alone (and the subsystem could just be one particle in a multiparticle entangled system). This is important in the analysis of decoherence, for example, where the approach apparently involves treating both the subsystem and its environment as being in a pure state, and then looking at how interactions between subsystem and environment change the reduced density matrix for the subsystem. That is clearly wrong, so the details are irrelevant. If you think like a > physicist, rather than as a mathematician, you look for the physics of what > a paper is saying. > > It isn't obviously wrong in my interpretation above, and I think it's wrongheaded to imagine you can be confident about the interpretation of any verbal statement by a physicist if you don't have a detailed grasp on the mathematics of the model the physicist is talking about--if you don't you may miss possible interpretations, like the ones above that you don't seem to have considered. Also, do you plan to respond to the rest of my comment? In particular, do you think you can come up with any simple numerical examples that show a local-copies-with-matching model can't correctly reproduce some observed statistics at a given location if we assume that location has been "shielded" from any physical influences from Alice or Bob (and assuming 'matching' between copies of Alice and copies of Bob can only be done in regions that have received measurable physical signals from them), as you seemed to claim earlier? Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Mon, Apr 25, 2016 at 10:16 PM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 26/04/2016 5:52 am, Jesse Mazer wrote: > > On Mon, Apr 25, 2016 at 2:58 AM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> >> >> I think you may have missed a salient feature of my little story about >> mismatching. The point to which I wish to draw attention is that Alice and >> Bob do not know that they are in an impossible world until after they have >> compared their experimental notes. In general, in order to do the matching >> in a way that will preserve the quantum correlations, you have to know the >> probabilities of the combined worlds in advance. But these probabilities >> can be calculated only after Alice and Bob exchange notes. >> > > What do you mean by "in advance"? There is no need to do any matching at > all until you look at a patch of spacetime that is in the overlap of the > future light cone of Alice's measurement and the future light cone of Bob's > measurement; and at that point, of course information about what detector > setting each one used can be available without violating locality. > > > That, of course, is the issue. How is that information available? It only > becomes available when Alice and Bob exchange notes -- there is no external > indication of that information before that time. > Available to who? The human experimenters? Of course in a general mathematical reformulation of quantum physics it would not actually be necessary for any humans to be aware of some information for it to have a physical effect. Any explicitly local model of physics should work a bit like a cellular automata--imagine a tiny computer at each point in spacetime, which receives information about the values of local variables (Bell's 'beables') at points in the past light cone, and uses them to determine what the value of the local variables at that point should be. The twist here would just be that the local variables at a given point would be a superposition of different possible values--the "copies"--and we can imagine the tiny computer at a given point C may need to do some matching of copies of events at A and copies of events at B in order to determine the set of copies at C. > So you need to know the relative orientations and results in order to >> calculate the probabilities required to get consistent matchings, but these >> probabilities become available only after the matching is complete. In >> other words, the model as proposed is incoherent. >> > > To do the matching, you only need the statistics of the fraction of copies > of Alice that used each setting, and the fraction of copies of Bob that > used each setting, which were determined at the time each one made their > measurement. > > > The matching must be made separately for each copy of Alice and Bob. > Overall statistics are relevant for matchings over repeated runs of the > experiment, but not otherwise. > I don't know what you mean by "made separately for each copy". Say for example a measurement made by Alice at one point in spacetime resulted in 3 copies A1, A2, A3 and a measurement made by Bob at a different point in spacetime resulted in 3 copies B1, B2, B3. And say each copy sends a causal influence (like a photon or some other particle) towards a third point P that lies in the future light cone of both of these points, with the exact nature of this causal influence being slightly different for each copy (for example, A1 might send a photon with a different frequency than A2, and A3 might send a photon with a third different frequency). The computer at P then receives the 3 slightly different copies of a causal influence from Alice, and the 3 slightly different copies of a causal influence from Bob. Then to determine the effect of the causal influences on copies P1,P2,P3 of some physical system located at P, it uses some kind of matching rule; let's say for example that it decides P1 was causally influenced by the matched pair (A1,B2), P2 was influenced by the matched pair (A2,B1), and P3 was influenced by the matched pair (A3,B3). Does this fit your criteria for a matching "made separately for each copy", and if not what part of this account violates it? >> > Well, if they have some ideal perfect shielding that perfectly prevents > any information from getting to a given point in the overlap of the future > light cones, then by definition the probabilities for physical events at > that point in spacetime won't depend on what result each got, so there's no > need to do any matching up of their measurement results at that point. > > > In which case their shielding has thwarted the quantum predictions. > I disagree, but if you think so, please present a specific

### Re: Non-locality and MWI

On Mon, Apr 25, 2016 at 2:58 AM, Bruce Kellettwrote: > > > I think you may have missed a salient feature of my little story about > mismatching. The point to which I wish to draw attention is that Alice and > Bob do not know that they are in an impossible world until after they have > compared their experimental notes. In general, in order to do the matching > in a way that will preserve the quantum correlations, you have to know the > probabilities of the combined worlds in advance. But these probabilities > can be calculated only after Alice and Bob exchange notes. > What do you mean by "in advance"? There is no need to do any matching at all until you look at a patch of spacetime that is in the overlap of the future light cone of Alice's measurement and the future light cone of Bob's measurement; and at that point, of course information about what detector setting each one used can be available without violating locality. > > So you need to know the relative orientations and results in order to > calculate the probabilities required to get consistent matchings, but these > probabilities become available only after the matching is complete. In > other words, the model as proposed is incoherent. > To do the matching, you only need the statistics of the fraction of copies of Alice that used each setting, and the fraction of copies of Bob that used each setting, which were determined at the time each one made their measurement. These fractions can depend arbitrarily on what rule each one used to pick their setting--for example, Alice could have used a deterministic pseudorandom algorithm in which case all copies of Alice will have chosen the same detector setting, or she could have used some independent quantum experiment (say, one involving radioactive decay) to choose her setting randomly with whatever probabilities she wanted, like 1/19 chance of setting 1, 5/19 chance of setting 2, and 13/19 chance of setting 3, in which case those will be the fraction of copies of Alice that chose each of those settings. Regardless of what the fractions were for each of Alice and Bob individually, once you reach the first point in spacetime where the future light cones of their measurements overlap, that point *can* have access to each one's statistics without locality (though it doesn't necessarily have to, see below), and given that information it's always possible to match them in a one-to-one way that gives the correct quantum statistics. Do you disagree with this, and if so which point? > > Again, Alice and Bob might try to thwart such a scenario by careful > shielding of their apparatus and not communicating with anyone. Once more, > I don't think quantum mechanics can be stymied by silence and lead > shielding. > Well, if they have some ideal perfect shielding that perfectly prevents any information from getting to a given point in the overlap of the future light cones, then by definition the probabilities for physical events at that point in spacetime won't depend on what result each got, so there's no need to do any matching up of their measurement results at that point. Similarly, in the idealized Schroedinger's cat thought-experiment where the inside of the box is perfectly shielded from leaking any information to the outside, there is no need to match up copies of the experimenter outside with copies of the cat inside, even if the experimenter is in the future light cone of the event of the cat having been saved/killed. Only when there is some physical event C whose local probability depends on the results of both prior events A and B is there a need to do any matching--and by definition, such a physical event C must have had some nonzero probability of getting a "signal" from both measurement-events. And in the many-worlds interpretation, C would actually be receiving a cluster of copies of different possible signals whose statistics would reflect the statistics of different measurement results. > > The real problem is that any theory which enables the gathering of such > information from the results of environmental decoherence would have to > involve radically new physics, of a kind that has never been seen before. > This would have to be universal physics -- we can't just dream up an ad hoc > theory that applies only to the correlations of entangled particles! > You still haven't given a clear answer the basic question I've been persistently asking you about: do you claim there is any airtight argument, akin to Bell's theorem (or perhaps based on Bell's theorem itself), which would allow us to prove mathematically it's not *possible* to come up with a local theory of copies and matching which is "general" in the sense of reproducing the correct quantum predictions for *arbitrary* experiments? Or are you just skeptical/incredulous based on your personal intuitions about what such a theory would need to look like, without claiming it's possible to rule out

### Re: Non-locality and MWI

On Fri, Apr 22, 2016 at 2:35 AM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 22/04/2016 2:46 pm, Jesse Mazer wrote: > > On Thu, Apr 21, 2016 at 11:25 PM, Bruce Kellett <bhkell...@optusnet.com.au > > wrote: > >> On 22/04/2016 12:53 pm, Jesse Mazer wrote: >> >> On Thu, Apr 21, 2016 at 9:49 PM, Bruce Kellett < >> <bhkell...@optusnet.com.au>bhkell...@optusnet.com.au> wrote: >> >>> >>> >>> The point here is that some combinations of results are forbidden. How >>> can this happen? >>> >> >> By the appropriate matching rules for locally-generated copies in >> different locations, as in my toy model. There's no reason you can't have >> something similar in a more general model, which I think is exactly what >> people like Rubin are presenting. >> >> >> The best I can make of this is that you have some theory that is not >> quantum mechanics. Quantum mechanics does not give any such "matching rules" >> > > It's important to distinguish between theories of physics and the > mathematical models used to express them--a physical theory is defined > entirely by the predictions about observable outcomes, not any elements of > the model that are not directly measurable even in principle. For example, > curved spacetime is not essential to general relativity as a theory, though > it is a feature of the most commonly-used mathematical model (there is an > alternate formulation that only uses flat spacetime, but has a field > defined on this spacetime which varies the length of rulers and the ticking > rate of clocks at different points in the spacetime, and physicists would > still call this 'general relativity'). Likewise, a state vector in Hilbert > space is not essential to quantum mechanics as a theory. And if one *could* > come up with a model involving "matching rules" that would be equivalent in > its predictions about observable measurement results as the existing > mathematical models, this would merely be a new mathematical model for the > same physical theory. > > > It would seem that you are not a physicist! What you claim here about > physics is actually quite contentious. It seems to constitute an extreme > form of instrumentalism. > I don't think that's the case, I'm basically just talking about how physicists *define* the physical content of a theory. But it would help if you would define what you mean by "instrumentalism". For example, some articles I found googling the term seem to say that it suggests we should not assign any "reality" to elements of the theory beyond the predictions about empirical measurements; I would say any talk of "reality" beyond measurements is more of a philosophical issue than a scientific one, but I don't see anything wrong with having opinions on such philosophical issues. In particular, if there is an element that seems to show up in *all* our mathematical models, like the notion of an "electron" which isn't absent from any formulation of quantum electrodynamics, it certainly makes sense to me to call it "real". Likewise, although we can't ever get evidence that space and matter continue beyond the boundary of the observable universe, it would require a very contrived model to avoid it (one which treated us as being at the exact center of real space, for example), so disbelieving it would to me seem like a ridiculous philosophical view, akin to solipsism (speaking of which, I could also potentially come up with a solipsistic interpretation of quantum physics in which I and only I am capable of collapsing the wavefunction with my observations, but this would seem equally ridiculous despite the fact that I can't come up with any experiment that would falsify it for me). Also, it seems from my googling that many instrumentalists would define the validity of scientific theories solely in terms of what we humans can actually verify in principle, giving up the notion of any objective truth about nature independent of what humans know. If so, I am not taking this position either. I'm saying the physical content of a theory is defined in terms of the complete set of predictions about things that could *in principle* be measured by some arbitrarily advanced physical being at the right place and time (so the fact that we may have no way of verifying most of the predictions of string theory at any time in the forseeable theory does not disqualify it as a scientific theory, for example), and I personally believe there is some objective truth about what mathematical relationship describes the complete set of in-principle-measurable facts about our physical universe. The basic point I was making with my point about physics theories vs. mathematical models is that I

### Re: Non-locality and MWI

On Thu, Apr 21, 2016 at 11:25 PM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 22/04/2016 12:53 pm, Jesse Mazer wrote: > > On Thu, Apr 21, 2016 at 9:49 PM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> >> >> The point here is that some combinations of results are forbidden. How >> can this happen? >> > > By the appropriate matching rules for locally-generated copies in > different locations, as in my toy model. There's no reason you can't have > something similar in a more general model, which I think is exactly what > people like Rubin are presenting. > > > The best I can make of this is that you have some theory that is not > quantum mechanics. Quantum mechanics does not give any such "matching rules" > It's important to distinguish between theories of physics and the mathematical models used to express them--a physical theory is defined entirely by the predictions about observable outcomes, not any elements of the model that are not directly measurable even in principle. For example, curved spacetime is not essential to general relativity as a theory, though it is a feature of the most commonly-used mathematical model (there is an alternate formulation that only uses flat spacetime, but has a field defined on this spacetime which varies the length of rulers and the ticking rate of clocks at different points in the spacetime, and physicists would still call this 'general relativity'). Likewise, a state vector in Hilbert space is not essential to quantum mechanics as a theory. And if one *could* come up with a model involving "matching rules" that would be equivalent in its predictions about observable measurement results as the existing mathematical models, this would merely be a new mathematical model for the same physical theory. If you disagree with any of this, please explain your disagreement. And if you don't disagree that physics theories are defined solely in terms of their predictions about measurement results, but you think there is something intrinsically impossible about the idea that a mathematical model involving "matching rules" could reproduce these predictions, please explain the argument, because it clearly can't just be Bell's theorem. > nor does it give any dynamics whereby such matching could be effected. So > you no longer have an interpretation of quantum mechanics, you have a > different theory. It remains for you to develop this in a way that is > convincing. > But I am not claiming I can definitely present such a model--though as I said, my *impression* is that Rubin's paper seems to be doing that--I'm just disputing the idea that you can state with certainty that no such model is possible, such that you are confident that Rubin's paper can't contain an example without actually needing to read and understand it in detail. > Following back the train of information exchange between the participants, >> and accepting that worlds, once decohered, cannot suddenly disappear, it >> becomes apparent that the zero probability branches cannot arise because >> they are forbidden at the stage when A and B are still at spacelike >> separations. So they are forbidden non-locally. >> > > But that clearly isn't true in my model, so there's no reason to think it > *must* be true in more general models that reproduce arbitrary quantum > measurements. In my model *and* in more general models of the sort that > people like Rubin seem to be proposing, until matching between Alice and > Bob has happened there *are* no "branches" containing facts about both of > their results, only a set of local branches for one region and a different > unrelated set of branches for another region. And once the two sets of > branches can interact, they can be matched up in a way that creates zero > probability of matching up a version of Alice who got + at zero degrees and > a version of Bob who got + at zero degrees. > > > But your model only reproduces the quantum correlations because you have > put them in by hand. That is not a viable model of physics. > I didn't claim it was, I only claimed it demonstrated that Bell's theorem does not present any fundamental obstacle to coming up with such a model. Remember, Bell's theorem too deals only with the predicted quantum correlations in specific experiments, and the proof doesn't depend at all on what mathematical theory was used to derive those predicted correlations. You claim that there are no branches containing facts about both A and B > until this matching takes place. The rules for this matching presumably say > that one must not match incompatible results. How is the matching done: > does one pick one result, and search about for a match that does not > violate the quantum statistics? You will

### Re: Non-locality and MWI

On Thu, Apr 21, 2016 at 9:49 PM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 22/04/2016 5:17 am, Jesse Mazer wrote: > > On Wed, Apr 20, 2016 at 7:51 PM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> On 21/04/2016 1:34 am, Jesse Mazer wrote: >> >> On Tue, Apr 19, 2016 at 8:54 PM, Bruce Kellett < >> <bhkell...@optusnet.com.au>bhkell...@optusnet.com.au> wrote: >> >>> So, the fact that these simulated results were supposed to have come >>> from an entangled singlet pair has not been used anywhere in your >>> simulation. It has only ever been used to link the copies of Alice and Bob, >>> the statistics that they observe come entirely from what you happen to put >>> in you accumulator for each setting of the relative orientations. >>> >> >> Saying the idea of a singlet pair "has not been used anywhere in your >> simulation" and then saying it has "been used to link the copies of Alice >> and Bob" seems like a contradiction--isn't the linking itself part of the >> simulation? >> >> No, there is no contradiction. You have used the fact that they are >> measuring parts of an entangled system only to link the sets of results. >> Nowhere have you used the quantum properties of the entangled singlet pair >> in the simulation to calculate the probabilities: you have imposed those >> probabilities from outside by fiat. >> > > Sure, it's a toy model so I just tailor it to give the correct statistics > for a single type of quantum experiment. But if I were to try to do the > same thing in a scheme where there *weren't* multiple copies of Alice and > Bob, so that each had to get a unique result *at the place and time they > make a measurement* (not just later when they compare results), then Bell's > theorem absolutely rules out doing this in any classical setup that > respects locality, even toy models. So, the toy model is just mean to > illustrate the principle that Bell's theorem isn't applicable to situations > where measurements don't yield unique outcomes but just yield a bunch of > different copies of a system at a given location in space at a given time. > > > interesting. So you agree that you just feed in the statistics that you > want to come out -- they do not come from any principle physics that your > computers simulate. > Yes, but they do come from rules which generate the results at each point in spacetime in a local way, depending only one what's in the past light cone of that point, and which generate the desired statistics. This proves the principle that Bell's theorem does not forbid rules of this "locally generated results on arbitrary patches" sort from reproducing the statistics of the particular experiments that Bell's theorem analyzes. Thus, Bell's theorem presents no fundamental obstacle to the hope of developing a set of rules that would generate correct results for *all* possible measurable behaviors of quantum systems, and which are still of the "locally generated results on arbitrary patches" type. Do you disagree? > > I am glad you agree that if you consider the actual physical situation, > locality is ruled out by the observed statistics. > Why should I agree to that? As I said, it obviously isn't ruled out by Bell's theorem, and if you have an alternate argument, you didn't respond to my request to present it in detail. > The fact that a measurement might yield one of a series of different > results does not alter the fact that, in the multiworlds picture, there is > only one result in each possible branch. > There are no such things as global "branches" in my toy model, only local copies of Alice and local copies of Bob that retroactively get matched up. Similarly, What Deutsch/Hayden/Rubin are all saying is that the same is true in their view of the many-worlds interpretation--there are no global branches, only local ones that join together in retrospect. If you disagree that this is what *they* are suggesting, I can give some quotes that show that this is their interpretation (along with other physicists talking about the MWI and saying the same thing--for example, I was just looking over a paper by the founder of the study of decoherence, H. Dieter Zeh, where he said essentially the same thing). If you agree this is what *they* try to suggest but think this is somehow incoherent, please present an argument for *why* it's incoherent as a general model of the laws of physics, when it clearly works fine in the toy model. > Once you accept this general principle, you can see that Bell's theorem > doesn't offer any fundamental obstacle to reformulating the general laws of > quantum mechanics in a way that yields the same predictions

### Re: Non-locality and MWI

On Wed, Apr 20, 2016 at 7:51 PM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 21/04/2016 1:34 am, Jesse Mazer wrote: > > On Tue, Apr 19, 2016 at 8:54 PM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> So, the fact that these simulated results were supposed to have come from >> an entangled singlet pair has not been used anywhere in your simulation. It >> has only ever been used to link the copies of Alice and Bob, the statistics >> that they observe come entirely from what you happen to put in you >> accumulator for each setting of the relative orientations. >> > > Saying the idea of a singlet pair "has not been used anywhere in your > simulation" and then saying it has "been used to link the copies of Alice > and Bob" seems like a contradiction--isn't the linking itself part of the > simulation? > > No, there is no contradiction. You have used the fact that they are > measuring parts of an entangled system only to link the sets of results. > Nowhere have you used the quantum properties of the entangled singlet pair > in the simulation to calculate the probabilities: you have imposed those > probabilities from outside by fiat. > Sure, it's a toy model so I just tailor it to give the correct statistics for a single type of quantum experiment. But if I were to try to do the same thing in a scheme where there *weren't* multiple copies of Alice and Bob, so that each had to get a unique result *at the place and time they make a measurement* (not just later when they compare results), then Bell's theorem absolutely rules out doing this in any classical setup that respects locality, even toy models. So, the toy model is just mean to illustrate the principle that Bell's theorem isn't applicable to situations where measurements don't yield unique outcomes but just yield a bunch of different copies of a system at a given location in space at a given time. Once you accept this general principle, you can see that Bell's theorem doesn't offer any fundamental obstacle to reformulating the general laws of quantum mechanics in a way that yields the same predictions about *all* observations using purely local equations, of the kind that could be simulated on a computer where you have a bunch of separate computers calculating how physical variables are evolving in a confined region of space, and each computer can only get data from other computers representing neighboring regions, in a locality-respecting way. As I said, my reading of the non-mathematical parts of Mark Rubin's paper suggests that the paper is coming up with exactly such a model, albeit one that is only equivalent to a non-relativistic quantum field theory (perhaps the math of doing it for a relativistic field theory would be more difficult). You seem to be saying this is impossible in principle, and you're confident enough of this to dismiss the possibility Rubin's paper has done this without apparently understanding the mathematical details either. So, given what I said above, should I take this to mean you think you have an argument for the impossibility which is entirely independent of Bell's theorem? If so you could you try to spell it out in a more detailed, step-by-step way? > No, I am simulating the system as it stands after Alice and Bob have > communicated, written their results on the tokens, and put them in the > appropriate urns. All completely local. > But then you are not simulating the observations each one gets at arbitrary times in a local way (the condition I mentioned earlier about all results being generated by the computers in realtime), your method is limited to a specific time after they have communicated. Bell's theorem is specifically about the impossibility of a local theory in which the results of each measurement must be generated when neither measurement result (or choice of detector setting) can have had a causal influence on the other (a spacelike separation in the context of relativity), and getting the correct statistics on the joint results. My toy model is meant to illustrate the point that Bell's theorem depends on the implicit assumption that each measurement yields a single unique result, and if you relax this and allow multiple copies, then you can have a theory which is still local and still generates the initial measurements at a spacelike separation, and also yields the correct joint outcomes for a randomly-selected copy of the experimenter once there's been time for the results to be communicated. > > Since you are accumulating joint results according to the statistics that > you have calculated on the basis of standard quantum mechanics, completely > independently of the properties of the actual singlets states that Alice > and Bob measure, my example is exactly equivalent to yours. > My example is relevant to Bell's theorem for the

### Re: Non-locality and MWI

On Tue, Apr 19, 2016 at 8:54 PM, Bruce Kellettwrote: > > So, the fact that these simulated results were supposed to have come from > an entangled singlet pair has not been used anywhere in your simulation. It > has only ever been used to link the copies of Alice and Bob, the statistics > that they observe come entirely from what you happen to put in you > accumulator for each setting of the relative orientations. > Saying the idea of a singlet pair "has not been used anywhere in your simulation" and then saying it has "been used to link the copies of Alice and Bob" seems like a contradiction--isn't the linking itself part of the simulation? After all, getting a message from Bob is part of the simulated world that Alice experiences, just as much as her own measurement. What we have here is just a single distributed simulation being run on multiple computers computing different parts of it in parallel, and communicating data in order to determine interactions between those parts. Any local physics model can be simulated in such a way, including ones that don't involve "copies" existing in parallel in a given region--for example, space can be divided into a cubic grid and each computer can compute the internal dynamics in each cube, and computers that simulate cubes that share a face in common can share there data so that particles or waves leaving one cube through a given face will appear in the neighboring cube from the same face. This would still be one big simulation, just computed in a distributed way. And the fact that you *can* distribute the computation of the whole universe into a bunch of local sub-simulations that communicate only with their neighbors is true if and only if the laws of physics governing your universe are "local" ones. > > I agree that you can generate the required statistics locally in this way. > In fact, I can do it even more simply by taking a number of urns and > labelling each with a particular relative orientation, say parallel, > antiparallel, 90 degrees, and so on. In the "parallel" urn I place a number > of tokens labeled (A+B-) and an equal number labelled (A-B+). In the > "antiparallel" urn, I place a number of tokens labelled (A+B+), and an > equal number labelled (A-B-). In the "90 degree" urn I place a number of > tokens labelled (A+B+), an equal number labelled (A+B-), an equal number > labelled (A-B+), and finally an equal number labelled (A-B-). > I don't see how your method would be a *local* simulation though. In order for it to be local, you'd need to set things up so Alice first picks her result from one of three urns at her location, and Bob first picks his result from one of three urns at his location, and they can see the result of their own pick before either one knows which urn the other one picked from. > But that is precisely what you toy model does. It has absolutely no > connection with EPR or real experiments. One could generate any arbitrary > set of statistics to satisfy any theory whatsoever by this method. You have > demonstrated absolutely nothing about the locality or otherwise of EPR. > Would you agree that in my toy model the results at each location can be generated in realtime (each experimenter finds out their own result before finding out the other one's result, and before they have any way of knowing what detector setting the other one used), and in a local way (the rule that generates a result that appears at a particular position and time doesn't depend on anything outside the past light cone of that event), and that the subjective probabilities for each experimenter match those of the EPR experiment? If you agree but think your urn model is doing the same, please explain it in more detail because as I said, your short description above doesn't seem to me to have these characteristics. Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Tue, Apr 19, 2016 at 12:06 AM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 19/04/2016 10:23 am, Jesse Mazer wrote: > > On Mon, Apr 18, 2016 at 3:45 AM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> >> The local mathematical rule in this case, say for observer A, is that >> measurement on his own local particle with give either |+> or |->, with >> equal probability. It does not matter how many copies you generate, the >> statistics remain the same. I am not sure whether your multiple copies >> refer to independent repeats of the experiment, or simply multiple copies >> of the observer with the result he actually obtained. The set of outcomes >> on the past light cone for this observer is irrelevant for the single >> measurement that we are considering. Taking such copies can be local, but >> the utility remains to be demonstrated. >> > > > Sorry if I was unclear, I thought we were on the same page about the > notion of "copies". The copies in my toy model are supposed to represent > the idea in the many-worlds that there are multiple equally-real versions > of a single system at a single location at a single time, including human > experimenters, and that in any quantum experiment some versions will record > one result and others will record a different one. So the copies represent > different parallel versions of a simulated observer, and just as in the > MWI, some copies see one result and other copies see a different result for > any *single* experiment (and each copy retains a memory, so different > copies remember different sequences of past results as well). And as in the > MWI, these copies would be unaware of one another--just imagine several > simulations of the same experimenter at the same time running in parallel, > with different variations on what results the simulation feeds to them. > > > I have a couple of questions. Firstly, does the ensemble generated in this > way differ in any significant respect from the one generated if the same > Alice and Bob perform their (random orientation) measurements a large > number of times? > If the probability of them selecting each possible detector setting on this single measurement is the same as the frequency with which they would select each detector setting on a large number of trials, then the statistics of results will also be the same. > And secondly, what exactly are they performing their measurements on? On > random unpolarized particles? or always on one of the particles of an > entangled singleton pair? > Within the context of the simulation, they are measuring the two members of an entangled pair. But the computer doesn't use any *actual* input from real-world instruments measuring entangled particle pairs, all computations and inputs are classical ones. > In the latter case, one would assume that we have to keep track of which > Alice result comes from the same pair as which Bob result. In other words, > the ensemble is identical to the one generated by many runs of the same > experiment, on entangled pairs, by the same observes. > That's true, the point here is just that you can generate these statistics using what I would define to be a "local" set of rules (see the bottom of this message for a discussion of what I understand 'local' rules to mean), and each copy has the *experience* of making only a single measurement and getting a single reported measurement from the other experimenter. > > > A common topic of discussion on everything-list is the subject of > "first-person indeterminacy", which would be expected to result when the > pattern of a given physical brain is duplicated (I haven't been following a > lot of recent threads so I don't know if you've already weighed in on this > topic before). You could imagine an actual atom-for-atom duplicate of a > biological person, but to avoid objections based on the uncertainty > principle and no-cloning theorem, let's instead suppose the person in > question is that of a "mind upload"--a very realistic simulation of a human > brain (at the level of synapses or lower) running on a computer, which most > on this list would assume would be just as conscious as a biological brain. > If the computer is a deterministic classical one, then if the simulated > brain is in a simulated body in a simulated environment which is closed off > from outside input and that also evolves deterministically, then if a copy > is made of the program with the same starting conditions and the copies run > in parallel on two different computers, the behavior (and presumably inner > experiences) of the upload should be the same. But say that after the two > programs have been running in paralle

### Re: Non-locality and MWI

On Mon, Apr 18, 2016 at 3:45 AM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 18/04/2016 5:00 pm, Jesse Mazer wrote: > > On Mon, Apr 18, 2016 at 1:37 AM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> On 18/04/2016 2:53 pm, Jesse Mazer wrote: >> >> On Sun, Apr 17, 2016 at 9:19 PM, Bruce Kellett < >> <bhkell...@optusnet.com.au>bhkell...@optusnet.com.au> wrote: >> >>> On 18/04/2016 10:11 am, Jesse Mazer wrote: >>> >>> On Sun, Apr 17, 2016 at 7:34 PM, Bruce Kellett < >>> <bhkell...@optusnet.com.au>bhkell...@optusnet.com.au> wrote: >>> >>>> >>>> The future light cones of the observers will overlap at a time >>>> determined by their initial separation, regardless of whether they send >>>> signals to each other or not. >>>> >>> >>> Of course, I never meant to suggest otherwise. Imagining a central >>> observer who receives messages about each experiment was just conceptually >>> simpler than imagining an arbitrary system that is affected in some >>> unspecified way by each experimenter's results along with every other part >>> of that system's past light cone. But you certainly don't *need* to use >>> that particular example. >>> >>> >>> The issue is to find a local explanation of the correlations: appealing >>> to some arbitrary system that is affected in some unspecified way. But my >>> example shows that no exchange of information after the separate worlds of >>> the two experimenters have fully decohered can ever explain the quantum >>> correlations. >>> >> >> Why do you think it shows that? Does "explain" mean something more than >> giving a mathematical model that generates the correct correlations, or is >> that sufficient? >> >> >> Have you not understood my argument? The specified experiment results in >> four possible combinations of results: |+>|+'>, |+>|-'>, |->|+'>, and >> |->|-'>. It is relatively easy to show, either by looking at special cases, >> or by consideration of a repeated sequence of such experiments, that the >> probabilities are different for each of the four sets of results. The >> differences in probability depend only on the relative orientations of the >> measuring magnets. Conveying this angle information after the experiment >> has been completed, and each of the measurements has totally decohered, >> cannot explain these correlations. >> >> What is required is an account of how these correlations can arise >> *before* A and B speak to each other, because once they have their >> results in hand, it may be weeks before they actually communicate. Rubin's >> argument (following from Deutsch) does not achieve this. >> > > > But as I said, you can achieve it if there is no fact of the matter about > *both* results except in the overlap region of the future light cone of > both measurements, where a single localized system may be causally > influenced by both measurements (see below for more on what I mean by this > if you're unclear). > > > >> >> >> This so-called "matching up" is pure fantasy. Who does this matching? If >>>> the central umpire is to do the matching, he has to have the power to >>>> eliminate cases that disagree with the quantum prediction. Who has that >>>> power? >>>> >>> >>> >>> The laws of physics would do the matching in some well-defined >>> mathematical way. >>> >>> >>> I agree that the laws of physics will 'prevent' the formation of any >>> worlds in which the laws of physics are violated. That is not the issue. >>> The issue is: how do the laws of physics act in order to achieve this. Do >>> they act locally or non-locally? If they act locally, then you are required >>> to provided the local mechanism whereby they so act. You are not doing this >>> at the moment. >>> >> >> Similar to my question above, what do you mean by "mechanism" ? Do you >> mean something more than simply "mathematical rule that gives you the set >> of possible outcomes (with associated probabilities or at least probability >> amplitudes) at each local region of spacetime, given only the set of >> possible outcomes at regions in the past light cone"? >> >> >> The mathematical rule that gives the differing probabilities for each >> outcome depending on the relative angle of the magnets is just qua

### Re: Non-locality and MWI

On Mon, Apr 18, 2016 at 1:37 AM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 18/04/2016 2:53 pm, Jesse Mazer wrote: > > On Sun, Apr 17, 2016 at 9:19 PM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> On 18/04/2016 10:11 am, Jesse Mazer wrote: >> >> On Sun, Apr 17, 2016 at 7:34 PM, Bruce Kellett < >> <bhkell...@optusnet.com.au>bhkell...@optusnet.com.au> wrote: >> >>> >>> The future light cones of the observers will overlap at a time >>> determined by their initial separation, regardless of whether they send >>> signals to each other or not. >>> >> >> Of course, I never meant to suggest otherwise. Imagining a central >> observer who receives messages about each experiment was just conceptually >> simpler than imagining an arbitrary system that is affected in some >> unspecified way by each experimenter's results along with every other part >> of that system's past light cone. But you certainly don't *need* to use >> that particular example. >> >> >> The issue is to find a local explanation of the correlations: appealing >> to some arbitrary system that is affected in some unspecified way. But my >> example shows that no exchange of information after the separate worlds of >> the two experimenters have fully decohered can ever explain the quantum >> correlations. >> > > Why do you think it shows that? Does "explain" mean something more than > giving a mathematical model that generates the correct correlations, or is > that sufficient? > > > Have you not understood my argument? The specified experiment results in > four possible combinations of results: |+>|+'>, |+>|-'>, |->|+'>, and > |->|-'>. It is relatively easy to show, either by looking at special cases, > or by consideration of a repeated sequence of such experiments, that the > probabilities are different for each of the four sets of results. The > differences in probability depend only on the relative orientations of the > measuring magnets. Conveying this angle information after the experiment > has been completed, and each of the measurements has totally decohered, > cannot explain these correlations. > > What is required is an account of how these correlations can arise > *before* A and B speak to each other, because once they have their > results in hand, it may be weeks before they actually communicate. Rubin's > argument (following from Deutsch) does not achieve this. > But as I said, you can achieve it if there is no fact of the matter about *both* results except in the overlap region of the future light cone of both measurements, where a single localized system may be causally influenced by both measurements (see below for more on what I mean by this if you're unclear). > > > This so-called "matching up" is pure fantasy. Who does this matching? If >>> the central umpire is to do the matching, he has to have the power to >>> eliminate cases that disagree with the quantum prediction. Who has that >>> power? >>> >> >> >> The laws of physics would do the matching in some well-defined >> mathematical way. >> >> >> I agree that the laws of physics will 'prevent' the formation of any >> worlds in which the laws of physics are violated. That is not the issue. >> The issue is: how do the laws of physics act in order to achieve this. Do >> they act locally or non-locally? If they act locally, then you are required >> to provided the local mechanism whereby they so act. You are not doing this >> at the moment. >> > > Similar to my question above, what do you mean by "mechanism" ? Do you > mean something more than simply "mathematical rule that gives you the set > of possible outcomes (with associated probabilities or at least probability > amplitudes) at each local region of spacetime, given only the set of > possible outcomes at regions in the past light cone"? > > > The mathematical rule that gives the differing probabilities for each > outcome depending on the relative angle of the magnets is just quantum > mechanics. But that is intrinsically non-local > I specified that I was talking about a local mathematical rule--I said the rule would give out the outcomes at one location in spacetime "given only the set of possible outcomes at regions in the past light cone". Did you miss that part, or do you disagree that if I mathematically determine the state of some region of spacetime using *only* information about the states of regions in the past light cone, that is by definition a local theory? > > You are claiming to have a

### Re: Non-locality and MWI

On Sun, Apr 17, 2016 at 9:19 PM, Bruce Kellett <bhkell...@optusnet.com.au> wrote: > On 18/04/2016 10:11 am, Jesse Mazer wrote: > > On Sun, Apr 17, 2016 at 7:34 PM, Bruce Kellett <bhkell...@optusnet.com.au> > wrote: > >> >> The future light cones of the observers will overlap at a time determined >> by their initial separation, regardless of whether they send signals to >> each other or not. >> > > Of course, I never meant to suggest otherwise. Imagining a central > observer who receives messages about each experiment was just conceptually > simpler than imagining an arbitrary system that is affected in some > unspecified way by each experimenter's results along with every other part > of that system's past light cone. But you certainly don't *need* to use > that particular example. > > > The issue is to find a local explanation of the correlations: appealing to > some arbitrary system that is affected in some unspecified way. But my > example shows that no exchange of information after the separate worlds of > the two experimenters have fully decohered can ever explain the quantum > correlations. > Why do you think it shows that? Does "explain" mean something more than giving a mathematical model that generates the correct correlations, or is that sufficient? > This so-called "matching up" is pure fantasy. Who does this matching? If >> the central umpire is to do the matching, he has to have the power to >> eliminate cases that disagree with the quantum prediction. Who has that >> power? >> > > > The laws of physics would do the matching in some well-defined > mathematical way. > > > I agree that the laws of physics will 'prevent' the formation of any > worlds in which the laws of physics are violated. That is not the issue. > The issue is: how do the laws of physics act in order to achieve this. Do > they act locally or non-locally? If they act locally, then you are required > to provided the local mechanism whereby they so act. You are not doing this > at the moment. > Similar to my question above, what do you mean by "mechanism" ? Do you mean something more than simply "mathematical rule that gives you the set of possible outcomes (with associated probabilities or at least probability amplitudes) at each local region of spacetime, given only the set of possible outcomes at regions in the past light cone"? Or would you say that such a mathematical rule would in itself be sufficient to qualify as what you mean by "mechanism"? If the latter, I already showed that you can have a mathematical rule that generates the correct correlations locally in a simple toy model involving experimenters at different locations measuring entangled particles, and I think the quote from Mark Rubin's paper at least strongly suggests he has a general mathematical model like this for arbitrary sets of particles, one where as he says, information is transferred from one location to another by a strictly "local differential equation". > If you don't yet see the difference, then you need to think about it a bit > more. > Could you please explain what *you* think is the difference? Just because someone doesn't come to the same conclusion as you doesn't mean they have simply failed to think about it sufficiently, it may be that there is some genuine foundational disagreement, but it's hard to determine unless the argument for the differing conclusion is made explicit. > Of course, what else? But the final claim is invalid: the EPR correlations > are not explained in such a way in the Everett (or any other) > interpretation. You either have non-locality or you have magic, unless you > go for 't Hooft's version of superdeterminism. You seem to be plumping for > magic. > Well, as above, I don't know whether "magic" simply refers to the lack of a mathematical rule, or if you think some rules that are mathematically well-defined and generate the correct statistics in a local way would nevertheless be dismissed as too magical. Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

On Sun, Apr 17, 2016 at 7:34 PM, Bruce Kellettwrote: > > The future light cones of the observers will overlap at a time determined > by their initial separation, regardless of whether they send signals to > each other or not. > Of course, I never meant to suggest otherwise. Imagining a central observer who receives messages about each experiment was just conceptually simpler than imagining an arbitrary system that is affected in some unspecified way by each experimenter's results along with every other part of that system's past light cone. But you certainly don't *need* to use that particular example. > >> This so-called "matching up" is pure fantasy. Who does this matching? If > the central umpire is to do the matching, he has to have the power to > eliminate cases that disagree with the quantum prediction. Who has that > power? > The laws of physics would do the matching in some well-defined mathematical way. I don't see this as fundamentally different from the fact that the laws of electromagnetism can be written in a form where the electric and magnetic potentials at each point in spacetime can be found by summing the potentials from all the charges and currents on the entire past light cone of that point (this neat approach is known as 'Lienard-Wiechert potentials', see https://www.av8n.com/physics/lienard-wiechert.htm for some discussion). Is it meaningful in that case to ask "who" is keeping track of each individual charge or current on the past light cone and adding up their potentials correctly to get the total? Also, what do you mean "eliminate cases"? Are you suggesting the frequencies of copies of each experimenter that get different possible results would have to be retroactively changed? I'm pretty sure that wouldn't be necessary, at least it isn't in the toy model I suggested. If on the other hand you just mean the laws are ensuring that you don't get combinations that aren't allowed by the laws themselves, again that just seems like the sort of thing you'd expect mathematical laws of physics to do. As I said, I don't understand the details of the Mark Rubin papers, but on p. 19-20 of the paper at http://arxiv.org/abs/quant-ph/0204024 he gives a more qualitative description of the model that the prior parts of the paper have explained mathematically, and it at least sounds as though it works in this way: "Information encoded in an operator at one place at an earlier time is transfered to operators at other places at later times in accordance with a local differential equation. (In a relativistic theory information is only transferred to later-time operators within the future light cone of the earlier-time operator.) Operator- valued wave packets corresponding to initially-separated particles may come into contact and exchange information. At any time, at any location, the value of the field operator is a weighted sum of products of initial-time field operators, as in (154), (155) (of course higher-order terms will in general be present). As one wave packet passes by another it may acquire contributions to this weighted sum which were “carried” to the interaction region by another wave packet corresponding to another particle. (E.g., via the O(ε) change to φ_V,[r]i due to the interaction term in eq. (154).) At later times operators in this wave packet will retain these contributions, serving as labels indicating that the encounter with the other wave packet took place. Depending on the nature of the initial conditions and the interaction, distant field operators at times subsequent to the interaction may be entangled in such a way that the results of measurements made upon them (when compared at still later times by means of some other causal interaction) are correlated to a degree in excess of that allowed by Bell’s theorem.5 As discussed in Ref. 22, correlations in the Everett interpretation are correlations of information exchanged in a causal manner between copies of measuring instruments and/or the states of awareness of observers, so these excess correlations in no way imply the presence of nonlocality." Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Non-locality and MWI

"A and B perform their measurements at spacelike separation, but each chooses the measurement orientation outside the light cone of the other. There are four possible combinations of results, corresponding to four worlds in the MWI: |+>|+'>, |+>|-'>, |->|+'>, and |->|-'>. Since each observer has a 50% chance of getting |+> and 50% of getting |->, and the two measurements are completely independent of each other, it would seem that each of these four worlds is equally likely." I don't think this is how it's supposed to work for those who argue the MWI is local like Deutsch. Rather the idea is that "splitting" into worlds is local, not global; so one experimenter locally splits into copies that see |+> and |-> when they measure their particle, likewise the other experimenter splits into copies that saw |+'> and |-'>. But until their future light cones overlap there are no "worlds" containing facts about what *both* experimenters saw. And once they do overlap--say, because they both sent signals about their results to an experimenter at the midpoint between them--then they can be matched up appropriately based on information in the past light cone of the overlap region, including information about what detector setting each copy of each experimenter used. So if both experimenters used the same detector setting, then if we consider the copy of the middle observer who gets matched up with the copy of the left experimenter that got |+>, he must also be matched up with the copy of the right experimenter that got |-'>, and likewise the copy of the middle observer who gets matched up with the copy of the left experimenter who got |-> must be matched up with the copy of the right experimenter that got |+'>. You could design a cellular-automata like system that keeps track of multiple copies of each system at a given "cell" in this sort of way, and reproduces the statistics seen in Bell experiments, so the idea is at least in principle consistent (I described a simple toy model at http://www.physicsforums.com/threads/does-mwi-resolve-locality-problems-with-entanglement.206291/#post-1557143 ). Although from what I've read, the "preferred basis problem" means the current formulation of the MWI has trouble getting probabilities from the universal wavefunction in any simple frequentist way (one where you have a well-defined "fraction of copies with property X vs. fraction with property Y" for each local region of spacetime, and probability is simply interpreted in terms of this fraction), instead probabilities are usually derived in non-frequentist ways using things like decision theory. Maybe in the future a nice frequentist version of the Everett interpretation will be found though...I don't understand the details, but I think Mark Rubin has been trying to get closer to something like this in the papers at http://arxiv.org/abs/quant-ph/0204024 and http://arxiv.org/abs/quant-ph/0511188 and http://arxiv.org/abs/0909.2673 Jesse On Fri, Apr 15, 2016 at 8:33 PM, Bruce Kellettwrote: > On 16/04/2016 12:20 am, Bruno Marchal wrote: > > On 14 Apr 2016, at 14:31, Bruce Kellett wrote: > > Although all possible combinations of measurement outcomes exist in MWI, > it is not clear what limits the results of the two observers to agree with > quantum mechanics when they meet up in just one of the possible worlds. > > > Because they have separated locally, and Alice's measurement just inform > both of them (directly for Alice and indirectly for Bob once some classical > bit of information is communicated by Alice to Bob by the usual means). > > > This is the purported solution given by Deutsch and Hayden, amongst many > others. Unfortunately, it does not work, as can be demonstrated by working > through a specific example. > > Consider the usual case of a spin singlet that splits into two spin-half > components that separate and are measured by A and B at spacelike > separation. There are two possible measurement results for each observer, > call them |+> and |->. The entangled state can then be written as: > >|psi> = (|+>|-> - |->|+>). > > ignoring normalization factors for simplicity. The first ket applies to > observer A and the second to observer B. > > This is the general expression for the singlet state in any basis, such as > would be define by the orientation of the measuring magnets. We denote the > measurement results in some other direction as |+'> and |-'>. > > A and B perform their measurements at spacelike separation, but each > chooses the measurement orientation outside the light cone of the other. > There are four possible combinations of results, corresponding to four > worlds in the MWI: |+>|+'>, |+>|-'>, |->|+'>, and |->|-'>. Since each > observer has a 50% chance of getting |+> and 50% of getting |->, and the > two measurements are completely independent of each other, it would seem > that each of these four worlds is equally likely. > > But this conclusion is contradicted

### Re: Anna Stubblefield

Isn't there a pretty strong consensus among the experts that "facilitated communication" is actually a Ouija board like phenomenon where the facilitator is actually determining all the letters through small muscle movements (the 'ideomotor effect'), whether consciously or subconsciously? >From what I understand, whenever they do tests where the disabled person is exposed to some sensory information that the facilitator doesn't have access to, they always appear to be ignorant of this information in the facilitated communication. Here's an article with more info on the case against it: http://www.skeptic.com/eskeptic/06-05-25/ This is also discussed in the article Brent linked to, and although it mentions that Anna believed some studies showed it work, no mention is made of any studies with this type of protocol where the facilitator has no way of knowing the answer but the disabled person should. The explanation that the facilitators don't want to put the disabled subjects on display like "show ponies" is unconvincing--surely it should be up to the disabled subjects to decide for themselves, and it would be a rather amazing uniformity of opinion among a large and diverse group if they *all* refused to participate in such tests (especially given that solid evidence of facilitated communication being genuine would probably result in considerable mainstreaming, meaning a lot more disabled people would get the opportunity to use it in the future). Jesse On Tue, Oct 20, 2015 at 6:59 PM, Brent Meekerwrote: > A strange, and sad, case. But Facilitated Communication would seem to be > a corollary of Bruno's idea that conscious persons are "out there" in > platonia and just need the proper physics in order to interact with us. > > > http://www.nytimes.com/2015/10/25/magazine/the-strange-case-of-anna-stubblefield.html?_r=0 > > Brent Meeker > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to everything-list+unsubscr...@googlegroups.com. > To post to this group, send email to everything-list@googlegroups.com. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: MGA revisited paper

On Sun, Aug 17, 2014 at 11:49 PM, Stathis Papaioannou stath...@gmail.com wrote: On Sunday, August 17, 2014, meekerdb meeke...@verizon.net wrote: On 8/16/2014 10:16 AM, Stathis Papaioannou wrote: On 16 August 2014 10:16, meekerdb meeke...@verizon.net wrote: On 8/15/2014 4:34 PM, Stathis Papaioannou wrote: I think these sorts of considerations show that the physical states cannot be responsible for generating or affecting consciousness. How do they show that? I thought they only showed that CC and environmental reference were necessary to consciousness. Are you assuming that the playback of a recording IS conscious? If it is true that a recording is conscious or the random states of a rock are conscious then I think that does imply that physical states are irrelevant to consciousness. But the argument goes that this irrelevance of physical states is absurd, so some restriction is imposed on what can be conscious in order to avoid the absurdity. One possible restriction is that consciousness only occurs if the computations are implemented relative to an environment, another is that the counterfactuals be present. But these are ad hoc restrictions, no better than saying that consciousness can only occur in a biological substrate. The immediate objection to this is that physical changes in the brain *do* affect consciousness. But if physical states cannot be responsible for generating or affecting consciousness, there can be no evidence for a separate, fundamental physical world. What we are left with is the platonic reality in which all computations are realised and physical reality is a simulation. It is meaningless to ask if consciousness supervenes on the computations implemented on the simulated rock or the simulated recording. It's not meaningless to ask if there must be simulated physics for the simulated consciousness to supervene on. Do you think you could be conscious of a world with no physics? Both consciousness and physics supervene on the computations, which exist necessarily. Consciousness does not supervene on the physics. Yes, I agreed to that. The question was can consciousness supervene on computations that do not instantiate any physics? I think not. I think that a sustained stream of consciousness will probably be part of a computation that instantiates physics - instantiates a whole universe complete with physics. However, the point that I wanted to make was that if computation can instantiate consciousness then there is nothing to stop a recording, a Boltzmann Brain, a rock and so on from doing so; for these possibilities have been used as arguments against computationalism or to arbitrarily restrict computationalism. As I argued earlier though, if you hypothesize that consciousness supervenes on the logical structure of computations, you can avoid the conclusion that a rock or a recording contributes just as much to the measure of a given human observer-moment as an actual human brain (or a detailed simulation of one, or any other physical process that contains the same pattern of logical relations between propositions about events within the process). Would you disagree that consciousness supervening on logical structure is one way to have a form of computationalism that avoids the conclusion that *any* system (including a rock) can be interpreted as an instantiation of any computation? This doesn't cover the issue of Boltzmann brains, since in a universe lasting an infinite time you could occasionally have systems randomly assemble that would perform the correct computations in the logical structure sense, but physicists who consider such things often suggest that in an inflationary multiverse, there would be some *physical* measure on different systems such that most instances of complex brain-like systems would appear in the early stages of an inflationary bubble universe, and that brain-like systems appearing randomly in very late high-entropy eras of bubble universes would be comparatively rare. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: MGA revisited paper

On Sat, Aug 16, 2014 at 12:48 AM, Pierz pier...@gmail.com wrote: On Saturday, August 16, 2014 2:28:32 PM UTC+10, jessem wrote: On Fri, Aug 15, 2014 at 11:09 PM, meekerdb meek...@verizon.net wrote: On 8/15/2014 5:30 PM, Jesse Mazer wrote: On Fri, Aug 15, 2014 at 1:27 AM, Russell Standish li...@hpcoders.com.au wrote: On Thu, Aug 14, 2014 at 09:41:00PM -0700, meekerdb wrote: On 8/14/2014 8:32 PM, Russell Standish wrote: On Thu, Aug 14, 2014 at 08:12:30PM -0700, meekerdb wrote: That does seem strange, but I don't know that it strikes me as *absurd*. Isn't it clearer that a recording is not a computation? And so if consciousness supervened on a recording it would prove that consciousness did not require computation? To be precise supervening on the playback of a recording. Playback of a recording _is_ a computation too, just a rather simple one. In other words: #include stdio.h int main() { printf(hello world!\n); return 1; } is very much a computer program (and a playback of recording of the words hello world when run). I could change hello world to the contents of Wikipedia, to illustrate the point more forcibly. OK. So do you think consciousness supervenes on such a simple computation - one that's functionally identical with a recording? Or does instantiating consciousness require some degree of complexity such that CC comes into play? My opinion on whether the recording is conscious or not aint worth a penny. Nevertheless, the definition of computational supervenience requires countefactual correctness in the class of programs being supervened on. AFAICT, the main motivation for that is to prevent recordings being conscious. I think it is possible to have a different definition of when a computation is instantiated in the physical world that prevents recordings from being conscious, a solution which doesn't actually depend on counterfactuals at all. I described it in the post at http://www.mail-archive.com/everything-list@googlegroups. com/msg16244.html (or https://groups.google.com/d/msg/everything-list/ GC6bwqCqsfQ/rFvg1dnKoWMJ on google groups). Basically the idea is that in any system following mathematical rules, including both abstract Turing machines and the physical universe, everything about its mathematical structure can be encoded as a (possibly infinite) set of logical propositions. So if you have a Turing machine running whose computations over some finite period are supposed to correspond to a particular observer moment, you can take all the propositions dealing with the Turing machine's behavior during that period (propositions like on time-increment 107234320 the read/write head moved to square 2398311 and changed the digit there from 0 to 1, and changed its internal state from M to Q), and look at the structure of logical relations between them (like proposition A and B together imply proposition C, proposition B and C together do not imply A, etc.). Then for any other computation or even any physical process, you can see if it's possible to find a set of propositions with a completely *isomorphic* logical structure. But physical processes don't have *logical* structure. Theories of physical processes do, but I don't think that serves your purpose. Propositions about physical processes have a logical structure, don't they? And wouldn't such propositions--if properly defined using variables that appear in whatever the correct fundamental theory turns out to be--have objective truth-values? Also, would you say physical processes don't have a mathematical structure? If you would say that, what sort of structure would you say they *do* have, given that we have no way of empirically measuring any properties other than ones with mathematical values? Any talk of physical properties beyond mathematical ones gets into the territory of some kind of thing-in-itself beyond all human comprehension. And even restricting the domain to Turing machines, I don't see what proposition A and proposition B are? They could be propositions about basic events in the course of the computation--state changes of the Turing machine and string on each time-step, like the example I gave on time-increment 107234320 the read/write head moved to square 2398311 and changed the digit there from 0 to 1, and changed its internal state from M to Q. There would also have to be propositions for the general rules followed by the Turing machine, like if the read/write head arrives at a square with a 1 and the machine's internal state is P, change the 1 to a 0, change the internal state to S, and advance along the tape by 3 squares. Aren't they just they transition diagram of the Turing machine? So if the Turing machine goes thru the same set of states that set defines an equivalence class of computations. But what about a different Turing machine that computes

### Re: MGA revisited paper

On Sat, Aug 16, 2014 at 9:44 AM, Pierz pier...@gmail.com wrote: On Saturday, August 16, 2014 11:26:08 PM UTC+10, jessem wrote: I think you're being misled by the particular example you chose involving addition, in general there is no principle that says finding the appropriate entry in a lookup table involves a computation just as complicated as the original computation without a lookup table. Suppose instead of addition, the lookup table is based on a Turing test type situation where an intelligent AI is asked to respond to textual input, and the lookup table is created by doing a vast number of runs, all starting from the same initial state but feeding the AI *all* possible strings of characters under a certain length (the vast majority will just be nonsense of course). Then all the possible input strings can be stored alphabetically, and if I interact with the lookup table by typing a series of comment to the AI, it just has to search through the recordings alphabetically to find one where the AI responded to that particular comment (after responding to my previous comments which constitute the earlier parts of the input string), it doesn't need to re-compute the AI's brain processes or anything like that. And ultimately regardless of the type of program, the input will be encoded as some string of 1's and 0's, so for *all* lookup tables the possible input strings can be stored in numerical order, analogous to alphabetical order for verbal statement No of course, a lookup table can help, as I went on to say a few minutes later in a different reply when I realized the mistake. But I've explained in my longer reply to Liz what I was trying to say here. It depends on what level we wish to simulate to. A mere lookup table of outer behaviours such as speech acts won't be sufficient for a complete simulation. The more fine grained and responsive I wish to make my simulation, the more computation will be required to select the correct recordings, and the shorter and shallower the recordings will be. But read my reply to Liz. Hopefully I explain myself better there. Well, in my example of the Turing test, if the AI was a mind upload, then the output could easily a detailed playback of all the activity in its simulated brain at the synaptic level as it was answering my questions, in addition to the AI's textual output. But it would still just be a *recording* of the brain activity it went through during the original creation of the lookup table, when the upload was simulated responding to every possible input sequence. By talking to the lookup table, I don't think I increase the measure of the experiences associated with the upload seeing my side of the dialogue and responding, though the original creation of the lookup table would have increased the measure associated with the all the experiences of seeing all the possible input strings. Note that even though an output showing detailed brain activity is very fine grained, it isn't true that more computation is required to select the correct recordings then if I just got textual output, nor are the recordings shorter and shallower. Perhaps you were talking about making the *input* more fine-grained? Suppose instead of just interacting with the upload via text, I want to have a virtual puppet body in the upload's simulated world (where the upload has his own simulated body), and I have a system that detects all the nerve signals leaving my brain and transfers them to the simulated motor neurons of the puppet body that the upload sees in front of him, and his physical responses (along with any changes in other physical objects in the virtual world) are translated into the appropriate signals to my sensory neurons, a la The Matrix. So here both the input and output are quite fine-grained. To create the lookup table, someone would have to run a host of simulations in which the puppet body interacting with the upload is fed *all* possible combinations of signals to its motor neurons, the vast majority of which would presumably lead it to flail around randomly, or perhaps be immobilized due to equal numbers of signals arriving at opposing muscle groups. This original work to create the lookup table is obviously computationally intensive, but if I want to later interact with the finished lookup table, finding the right recorded output to feed to my sensory neurons in response to my bodily output should be much less difficult then the original simulation needed to create that recording. The original simulation would require simulating all the physical changes in the virtual world, including the upload's brain activity, moment-by-moment to see how everything reacts to the motor neuron outputs fed to the puppet body. On the other hand, finding the appropriate response to my motor neuron outputs on the lookup table is just a matter of coding my motor neuron outputs as 1's and 0's, then looking up that sequence in a table of sequences

### Re: MGA revisited paper

On Fri, Aug 15, 2014 at 1:27 AM, Russell Standish li...@hpcoders.com.au wrote: On Thu, Aug 14, 2014 at 09:41:00PM -0700, meekerdb wrote: On 8/14/2014 8:32 PM, Russell Standish wrote: On Thu, Aug 14, 2014 at 08:12:30PM -0700, meekerdb wrote: That does seem strange, but I don't know that it strikes me as *absurd*. Isn't it clearer that a recording is not a computation? And so if consciousness supervened on a recording it would prove that consciousness did not require computation? To be precise supervening on the playback of a recording. Playback of a recording _is_ a computation too, just a rather simple one. In other words: #include stdio.h int main() { printf(hello world!\n); return 1; } is very much a computer program (and a playback of recording of the words hello world when run). I could change hello world to the contents of Wikipedia, to illustrate the point more forcibly. OK. So do you think consciousness supervenes on such a simple computation - one that's functionally identical with a recording? Or does instantiating consciousness require some degree of complexity such that CC comes into play? My opinion on whether the recording is conscious or not aint worth a penny. Nevertheless, the definition of computational supervenience requires countefactual correctness in the class of programs being supervened on. AFAICT, the main motivation for that is to prevent recordings being conscious. I think it is possible to have a different definition of when a computation is instantiated in the physical world that prevents recordings from being conscious, a solution which doesn't actually depend on counterfactuals at all. I described it in the post at http://www.mail-archive.com/everything-list@googlegroups.com/msg16244.html (or https://groups.google.com/d/msg/everything-list/GC6bwqCqsfQ/rFvg1dnKoWMJ on google groups). Basically the idea is that in any system following mathematical rules, including both abstract Turing machines and the physical universe, everything about its mathematical structure can be encoded as a (possibly infinite) set of logical propositions. So if you have a Turing machine running whose computations over some finite period are supposed to correspond to a particular observer moment, you can take all the propositions dealing with the Turing machine's behavior during that period (propositions like on time-increment 107234320 the read/write head moved to square 2398311 and changed the digit there from 0 to 1, and changed its internal state from M to Q), and look at the structure of logical relations between them (like proposition A and B together imply proposition C, proposition B and C together do not imply A, etc.). Then for any other computation or even any physical process, you can see if it's possible to find a set of propositions with a completely *isomorphic* logical structure. In the case of the physical world, it seems to me you could do this using only propositions about physical events that actually occur, along with the general laws governing them--no propositions about counterfactuals would be needed. I suggested something like this to Bruno, and he seemed to agree that at least in the case of computational *simulations* of the physical world, if you use a rule like this to define when a simpler computation is instantiated within some more detailed physical simulation, it would be the case that a detailed simulation of a physical computer running some simpler program P would qualify as instantiating P, whereas a detailed simulation of a physical device that was really just playing back a recording of a computer program (like Bruno's movie graph where all the optical gates have been replaced by projected images) would *not* instantiate P. See my comment at https://groups.google.com/d/msg/everything-list/Ljp3s2885Co/kght-F5LZeUJ and Bruno's response at https://groups.google.com/d/msg/everything-list/Ljp3s2885Co/__PZn6hmCb4J Assuming this idea for defining instantiations of sub-computations within larger computations makes sense, why wouldn't it make just as much sense if instead of propositions about computer programs running detailed physical simulations, you instead considered propositions about actual events and physical laws (but not counterfactuals) that are true in the physical universe, and looked for collections of propositions whose internal logical relations were isomorphic to those of some program? Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: MGA revisited paper

On Fri, Aug 15, 2014 at 11:09 PM, meekerdb meeke...@verizon.net wrote: On 8/15/2014 5:30 PM, Jesse Mazer wrote: On Fri, Aug 15, 2014 at 1:27 AM, Russell Standish li...@hpcoders.com.au wrote: On Thu, Aug 14, 2014 at 09:41:00PM -0700, meekerdb wrote: On 8/14/2014 8:32 PM, Russell Standish wrote: On Thu, Aug 14, 2014 at 08:12:30PM -0700, meekerdb wrote: That does seem strange, but I don't know that it strikes me as *absurd*. Isn't it clearer that a recording is not a computation? And so if consciousness supervened on a recording it would prove that consciousness did not require computation? To be precise supervening on the playback of a recording. Playback of a recording _is_ a computation too, just a rather simple one. In other words: #include stdio.h int main() { printf(hello world!\n); return 1; } is very much a computer program (and a playback of recording of the words hello world when run). I could change hello world to the contents of Wikipedia, to illustrate the point more forcibly. OK. So do you think consciousness supervenes on such a simple computation - one that's functionally identical with a recording? Or does instantiating consciousness require some degree of complexity such that CC comes into play? My opinion on whether the recording is conscious or not aint worth a penny. Nevertheless, the definition of computational supervenience requires countefactual correctness in the class of programs being supervened on. AFAICT, the main motivation for that is to prevent recordings being conscious. I think it is possible to have a different definition of when a computation is instantiated in the physical world that prevents recordings from being conscious, a solution which doesn't actually depend on counterfactuals at all. I described it in the post at http://www.mail-archive.com/everything-list@googlegroups.com/msg16244.html (or https://groups.google.com/d/msg/everything-list/GC6bwqCqsfQ/rFvg1dnKoWMJ on google groups). Basically the idea is that in any system following mathematical rules, including both abstract Turing machines and the physical universe, everything about its mathematical structure can be encoded as a (possibly infinite) set of logical propositions. So if you have a Turing machine running whose computations over some finite period are supposed to correspond to a particular observer moment, you can take all the propositions dealing with the Turing machine's behavior during that period (propositions like on time-increment 107234320 the read/write head moved to square 2398311 and changed the digit there from 0 to 1, and changed its internal state from M to Q), and look at the structure of logical relations between them (like proposition A and B together imply proposition C, proposition B and C together do not imply A, etc.). Then for any other computation or even any physical process, you can see if it's possible to find a set of propositions with a completely *isomorphic* logical structure. But physical processes don't have *logical* structure. Theories of physical processes do, but I don't think that serves your purpose. Propositions about physical processes have a logical structure, don't they? And wouldn't such propositions--if properly defined using variables that appear in whatever the correct fundamental theory turns out to be--have objective truth-values? Also, would you say physical processes don't have a mathematical structure? If you would say that, what sort of structure would you say they *do* have, given that we have no way of empirically measuring any properties other than ones with mathematical values? Any talk of physical properties beyond mathematical ones gets into the territory of some kind of thing-in-itself beyond all human comprehension. And even restricting the domain to Turing machines, I don't see what proposition A and proposition B are? They could be propositions about basic events in the course of the computation--state changes of the Turing machine and string on each time-step, like the example I gave on time-increment 107234320 the read/write head moved to square 2398311 and changed the digit there from 0 to 1, and changed its internal state from M to Q. There would also have to be propositions for the general rules followed by the Turing machine, like if the read/write head arrives at a square with a 1 and the machine's internal state is P, change the 1 to a 0, change the internal state to S, and advance along the tape by 3 squares. Aren't they just they transition diagram of the Turing machine? So if the Turing machine goes thru the same set of states that set defines an equivalence class of computations. But what about a different Turing machine that computes the same function? It may not go thru the same states even for the same input and output. In fact there is one such Turing machine that just executes

### Re: CTM and the UDA (again!)

On Sun, Jul 27, 2014 at 10:46 AM, David Nyman da...@davidnyman.com wrote: On 23 July 2014 17:49, Jesse Mazer laserma...@gmail.com wrote: So, why not adopt a Tegmark-like view where a physical universe is *nothing more* than a particular abstract computation, and that can give us a well-defined notion of which sub-computations are performed within it by various physical processes? Essentially because of the argument of Step 7 of the UDA. The assumption here is that consciousness (i.e. the logic of the first-person) is derived from computation. It then follows that we cannot ignore the possibility in principle of building a computer that not only implements a UD but also runs it for long enough to generate its infinite trace, UD* (incorporating, by the way, a fractal-like infinity of such dovetailing). If denying such a possibility on grounds of a lack of primitively-physical resources is evasive, to deny it on grounds of a lack of mathematical resources is surely merely incoherent. But if we do not deny it, but rather embrace it, we can see that such a structure would inevitably dominate any observational reality. I don't see why that should follow at all, as long as there are multiple infinite computations running rather than the UDA being the only one, there's no particular reason why the UDA computation should dominate in terms of its contribution to measure. See my most recent post to Bruno at http://www.mail-archive.com/everything-list@googlegroups.com/msg55617.html , particularly this paragraph where I give a possible definition for how one could define physical measure: 'For example, say after N steps of the universal computation U, we can count the number of times that some computation A has been executed within it, and the number of times that another computation B has been executed within it, and take the ratio of these two numbers; if this ratio approaches some limit in the limit as N goes to infinity, then this limit ratio could be defined as the ratio of the physical measure of A and B within the universe/multiverse. So if A and B are two possible future observer-moments for my current observer moment (say, an observer-moment finding itself in Washington and another finding itself in Moscow in your thought-experiment), then the ratio of their physical measure could be the subjective probability that I will experience either one as my next-observer moment.' Would you say that even if we define physical measure this way, and even if multiple infinite computations are running alongside the UDA computation, for some reason the UDA computation will dominate? Consider the situation I imagined in this paragraph of the same post: 'Also note that even if we have two different candidates for the physical universe computation, call them U and U', and even if both contain a never-ceasing universal dovetailer computation within them, it seems to me this is not enough to guarantee that U and U' will both assign the same physical measure to any two computations A and B, if we use a procedure like the one I outlined to define physical measure. Even though U and U' will both compute all the same programs eventually since they both contain a universal dovetailer, some programs might be computed more frequently (more copies have been run after N steps) in U than in U'. For example, U might be a physical simulation of a universe containing one physical computer that's computing the universal dovetailer along with 1000 physical computers computing copies of my brain experiencing being in Washington, while U' might be a physical simulation of a universe containing one physical computer that's computing the universal dovetailer along with 1000 physical computers computing copies of my brain experiencing being in Moscow.' To be more specific, imagine that these 1000 other simulated computers are running *infinite* iterations of the me in Washington simulation--for example, first it could spawn a copy of me arriving in Washington at 3 PM and simulate my 1st hour experienced in Washington from 3 PM to 4 PM, then it could spawn a newly-minted copy #2 of my brain and newly-minted copy of Washington at 3 PM and re-simulate my brain's 1st hour in Washington from 3 PM to 4 PM, then it could go back to copy #1 and simulate its second hour in Washington, then it could simulate copy #1's third hour, then it could simulate copy #2's second hour, then it could spawn a new copy #3 and simulate its first hour, and keep going this way following the same ordering that Cantor used to order the rational numbers as shown at http://www.homeschoolmath.net/teaching/rationals-countable.gif (with the numerator as the copy # and the denominator as the hour #). Since such a computer is constantly simulating copies of me in Washington, while the UDA is only very occasionally simulating copies of me in Washington or Moscow between all the other Turing machine programs it must simulate, then if I want

### Re: CTM and the UDA (again!)

On Sun, Jul 27, 2014 at 1:13 PM, David Nyman da...@davidnyman.com wrote: On 27 July 2014 17:27, Jesse Mazer laserma...@gmail.com wrote: I don't see why that should follow at all, as long as there are multiple infinite computations running rather than the UDA being the only one, I may be missing some other point you're making, but I think this is already dealt with after Step 8 of the UDA (universal dovetailer argument). By this point in the argument, we have abandoned the notion of a primitively-physical universe. But when you say by this point in the argument, do you mean there was some earlier step that established some good *reasons* for why we should abandon the notion of a primitively-physical universe (or primitive universal computation), or is it just something that was posited at some point for the purposes of exploring the consequences, without any claim that this posit was implied by earlier steps in the argument? As I said, it seems that someone could accept everything in steps 1-6 of Bruno's argument but still posit that the measure of each observer-moment would be determined by its limit frequency in some unique universe-computation U. Given that we are assuming CTM, we need some ontology to fix the notion of computation, and arithmetical relations suffice for this purpose. Sorry, what does CTM stand for? It doesn't appear anywhere in Bruno's Comp (2013) paper which I'm using for reference. BTW, I suggested an ontology in the earlier comment to Bruno at http://www.mail-archive.com/everything-list@googlegroups.com/msg16244.html -- basically using an axiomatic system which allows you to deduce the truth-value of various propositions about a computation, propositions equivalent to statements like after N time steps, the read/write head of the Turing machine moves to space 1185 on the Turing tape, finds a 0 there, changes its internal state from #5 to #8 and changes the digit there to 1. Then, a given computation can be defined in terms of the logical relations between a set of propositions, so one computation A can contain an instance of another computation B if some subset of propositions about A have an isomorphic structure of logical relations to the logical relations between propositions about B. Since the structure of arithmetic can also be defined in terms of a set of propositions with logical relations between them, and any statement about a particular computation can be decided by determining the truth-value of a corresponding statement about arithmetic, it may be that defining computations in terms of arithmetical relations would lead to all the same conclusions as the definition I suggest above, though I'm not sure. Such a Library must in particular contain universal dovetailers that themselves generate every possible program and execute each of them in sequence by means of dovetailing. This must include recursively regenerating themselves in an infinitely fractal manner. This characteristic implies a quite extraordinarily explosive regenerative redundancy. Hence it seems plausible a priori, even without a detailed calculus, that the resulting computational structure (i.e. the infinite trace of the UD, or UD*) must completely dominate any measure competition within the computational landscape defined by arithmetical truth (or the small part of it needed for the assumption). That seems very handwavey to me, and while it might seem plausible initially I think it becomes less so when you think more carefully about how measure might actually be assigned. Do you disagree that if we use the particular definition of measure I suggest, in the example I gave with U and U' (both containing a universal dovetailer alongside a bunch of other computers churning out endless copies of me in Washington or me in Moscow) the UD will *not* dominate the measure competition, in that U and U' will give very different answers to the relative likelihood that I find myself in Washington vs. Moscow in Bruno's thought-experiment? Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: CTM and the UDA (again!)

On Sun, Jul 27, 2014 at 2:04 PM, David Nyman da...@davidnyman.com wrote: On 27 July 2014 18:46, Jesse Mazer laserma...@gmail.com wrote: But when you say by this point in the argument, do you mean there was some earlier step that established some good *reasons* for why we should abandon the notion of a primitively-physical universe (or primitive universal computation), or is it just something that was posited at some point for the purposes of exploring the consequences, without any claim that this posit was implied by earlier steps in the argument? No, it is the strong implication of Step 7 on the basis of Steps 0-6, Well, this is precisely what I'm asking about, I don't see why abandoning the notion of a primitive universal computation is *implied* by anything that comes in steps 0-6, even after reading Bruno's Comp (2013) paper. Do you see any way in which the hypothesis I've suggested, which assigns measure to various sub-computations based on their frequency within a single universal computation U, contradicts anything in steps 0-6? I'm still identifying each observer-moment with one of those sub-computations, and saying the subjective probabilities of various possible next moments should depend on their measure (perhaps combined with some kind of informational continuity, since I'm presumably not going to experience becoming a brain-pattern with a totally different set of memories and personality, even if that brain-pattern has a high measure of its own), not on any sort of physical continuity. and the only option available after Step 8, But again, why? What about step 8 contradicts the hypothesis I've suggested? Bruno seemed to agree in previous discussion that a simulated world containing a movie-graph version of me would *not* contain my program in the isomorphic logical structure sense I discussed, whereas a simulated world containing a simulated physical computer running my program would. and while it might seem plausible initially I think it becomes less so when you think more carefully about how measure might actually be assigned. Do you disagree that if we use the particular definition of measure I suggest, in the example I gave with U and U' (both containing a universal dovetailer alongside a bunch of other computers churning out endless copies of me in Washington or me in Moscow) the UD will *not* dominate the measure competition, in that U and U' will give very different answers to the relative likelihood that I find myself in Washington vs. Moscow in Bruno's thought-experiment? Well, a bunch of other computers still seems to assume something more primitive than the simple assumption of arithmetic for the ontology. In terms of the UDA, all bunches of computers are already subsumed within the infinite redundancy of UD*. Again I am asking about the logic that explains *why* we should abandon the notion of a primitive universal computation given that we agree with steps 1-6. I thought when you said the UD would dominate, you were trying to give an argument for why any notion of a primitive universal computation would somehow become irrelevant to determining measure as long as we assume it contains an eternally-running UD (which if true would certainly be a good argument for abandoning the primitive universal computation as an irrelevant hypothesis, like the argument for abandoning an absolute reference frame in relativity because even if it existed it would have no measurable consequences). Maybe I misunderstood you, though. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: CTM and the UDA (again!)

On Thu, Jul 24, 2014 at 2:44 PM, Bruno Marchal marc...@ulb.ac.be wrote: HI Jesse, David, On 23 Jul 2014, at 18:49, Jesse Mazer wrote: Had some trouble following your post (in part because I don't know all the acronyms), but are you talking about the basic problem of deciding which computations a particular physical process can be said to implement or instantiate? If so, see my post at http://www.mail-archive.com/everything-list%40googlegroups.com/msg43484.html and Bruno's response at http://www.mail-archive.com/everything-list%40googlegroups.com/msg43489.html . I think from Bruno's response that he agrees that there is a well-defined way of deciding whether one abstract computation implements/instantiates some other abstract computation within itself (like if I have computation A which is a detailed molecular-level simulation of a physical computer, and the simulated computer is running another simpler computation B, then the abstract computation A can be said to implement computation B within itself). So, why not adopt a Tegmark-like view where a physical universe is *nothing more* than a particular abstract computation, and that can give us a well-defined notion of which sub-computations are performed within it by various physical processes? This approach could also perhaps allow us to define the number of separate instances of a given sub-computation within the larger computation that we call the universe, giving some type of measure on different subcomputations within that computational universe (useful for things like Bostrom's self-sampling assumption, which in this case would say we should reason as if we were randomly chosen from all self-aware subcomputations). So for example, if many copies of a given AI program are run in parallel in a computational universe, that AI could have a larger measure within that computational universe than an AI program that is only ever run once within it...of course, this does not rule out the possibility that there are other parallel computational universes where the second program is run more often, as would be implied by Tegmark's thesis and also by Bruno's UDA. But there is still at least the theoretical possibility that the multiverse is false and that only one unique computational universe exists, so the idea that all possible universes/computations are equally real cannot be said to follow logically from COMP. To have the computations, all you need is a sigma_1 complete theory and/or a Turing universal machine, or system, or language. Not sure I understand what you mean by have the computations, and I didn't understand the mathematical arguments you made following that. My point above is basically that even if one accepts steps 1-6 of your argument, which together imply that I should identify my self/experience with a particular computation (or perhaps a finite sequence of computational steps rather than an infinite computation, but I'll just call such a finite sequence a 'computation' to save time), it still seems to me that there is an open possible that the *measure* on different computations is defined by how often each one is physically instantiated. Are you talking about some deriving some unique measure on all computations when you say to have the computations, all you need... or are you not talking about the issue of measure at all? The idea I'm suggesting for a physically based measure involves identifying the physical universe/multiverse with a particular unique computation--basically, consider a computation corresponding to something like a Planck-level simulation of our universe, or an exact simulation of the evolution of the the universal wavefunction, then say that this computation *is* what we mean by the physical universe/multiverse. Then, if you agree there is some well-defined notion of whether a given computation contains within it some other computation (and that we can count the number of times some sub-computation has run within the larger computation after N steps of the larger computation), the measure on all computations could be determined by how frequently they each appear in the unique computation that we identify with the physical universe/multiverse. For example, say after N steps of the universal computation U, we can count the number of times that some computation A has been executed within it, and the number of times that another computation B has been executed within it, and take the ratio of these two numbers; if this ratio approaches some limit in the limit as N goes to infinity, then this limit ratio could be defined as the ratio of the physical measure of A and B within the universe/multiverse. So if A and B are two possible future observer-moments for my current observer moment (say, an observer-moment finding itself in Washington and another finding itself in Moscow in your thought-experiment), then the ratio of their physical measure could be the subjective probability

### Re: CTM and the UDA (again!)

Had some trouble following your post (in part because I don't know all the acronyms), but are you talking about the basic problem of deciding which computations a particular physical process can be said to implement or instantiate? If so, see my post at http://www.mail-archive.com/everything-list%40googlegroups.com/msg43484.html and Bruno's response at http://www.mail-archive.com/everything-list%40googlegroups.com/msg43489.html . I think from Bruno's response that he agrees that there is a well-defined way of deciding whether one abstract computation implements/instantiates some other abstract computation within itself (like if I have computation A which is a detailed molecular-level simulation of a physical computer, and the simulated computer is running another simpler computation B, then the abstract computation A can be said to implement computation B within itself). So, why not adopt a Tegmark-like view where a physical universe is *nothing more* than a particular abstract computation, and that can give us a well-defined notion of which sub-computations are performed within it by various physical processes? This approach could also perhaps allow us to define the number of separate instances of a given sub-computation within the larger computation that we call the universe, giving some type of measure on different subcomputations within that computational universe (useful for things like Bostrom's self-sampling assumption, which in this case would say we should reason as if we were randomly chosen from all self-aware subcomputations). So for example, if many copies of a given AI program are run in parallel in a computational universe, that AI could have a larger measure within that computational universe than an AI program that is only ever run once within it...of course, this does not rule out the possibility that there are other parallel computational universes where the second program is run more often, as would be implied by Tegmark's thesis and also by Bruno's UDA. But there is still at least the theoretical possibility that the multiverse is false and that only one unique computational universe exists, so the idea that all possible universes/computations are equally real cannot be said to follow logically from COMP. Jesse On Wed, Jul 23, 2014 at 9:38 AM, David Nyman da...@davidnyman.com wrote: Recent discussions, mainly with Brent and Bruno, have really got me thinking again about the issues raised by CTM and the UDA. I'll try to summarise some of my thoughts in this post. The first thing to say, I think, is that the assumption of CTM is equivalent to accepting the existence of an effectively self-contained computationally-observable regime (COR). By its very definition, the COR sets the limits of possible physical observation or empirical discovery. In principle, any physical phenomenon, whatever its scale, could be brought under observation if only we had a big enough collider. But by the same token, no matter how big the collider, no such observable could escape its confinement within the limits of the COR. If we accept that the existence of a COR is entailed by assuming CTM, we come naturally to the question of what might be doing the computation. In terms of the UDA, by the time we get to Step 7, it should be obvious that, in principle, we could build a computer from primitive physical components that would effectively implement the infinite trace of the UD (UD*). Furthermore, if such a computer were indeed to be implemented, the COR would necessarily exist in its entirety somewhere within the infinite redundancy of that trace. This realisation alone might well persuade us, on grounds of explanatory parsimony and the avoidance of somewhat strained or ad hoc reservations, to accept FAPP that UD*-COR. Should we be so persuaded, any putative underlying physical computer would have already become effectively redundant to further explanation. Notwithstanding this, we may still feel the need to retain reservations of practicability. Perhaps the physical universe isn't actually sufficiently robust to permit the building of such a computer? Or, even if that were granted, could it not just be the case that no such computer actually exists? Reservations of this sort can indeed be articulated, although worryingly, they may still seem to leave us rather vulnerable to being captured by Bostrom-type simulation scenarios. The bottom line however seems to be this: Under CTM, can we justify the singularisation, or confinement, of a computation, and hence whatever is deemed to be observable in terms of that computation, to some particular physical computer (e.g. a brain)? More generally, can we limit all possibility of observation to a particular class of computations wholly delimited by the activity of a corresponding sub-class of physical objects (uniquely characterisable as physical computers) within the limits of a definitively physical universe? This is

### Re: The Higgs and SUSY vs the Multiverse

Hopefully someone with a better understanding of these things will comment, but I believe it has to do with what physicists call the hierarchy problem, here are some links for your perusal: http://profmattstrassler.com/articles-and-posts/particle-physics-basics/the-hierarchy-problem/ http://profmattstrassler.com/articles-and-posts/some-speculative-theoretical-ideas-for-the-lhc/supersymmetry/supersymmetry-what-is-it/ http://scienceblogs.com/startswithabang/2013/05/15/the-rise-and-fall-of-supersymmetry/ http://www.quantumdiaries.org/2012/07/01/the-hierarchy-problem-why-the-higgs-has-a-snowballs-chance-in-hell/ http://en.wikipedia.org/wiki/Hierarchy_problem And I don't think the physicists are really saying that 115 GeV Higgs would rule out any sort of multiverse or need for anthropic arguments to explain various constants of nature, just that it would allow for a non-anthropic, supersymmetery-based explanation for *this particular* lucky (for life) value of the Higgs mass, that is neither zero nor near the Planck scale. Jesse On Sat, Jul 19, 2014 at 11:38 PM, LizR lizj...@gmail.com wrote: We've just been watching Particle Fever - a documentary about the LHC (from 2007 to the discovery of the Higgs boson last year). In it, at least a couple of people (Monica Dunbar and David Kaplan, IIRC) say that a 115GeV Higgs would be a clear sign of Supersymmetry, while a 140GeV (or greater) would indicate a Multiverse (meaning a String Landscape, I assume). The measured value is 126GeV, which apparently leaves everything open for now. They seem quite certain that there is a dichotony - SUSY vs MV - and that the MV answer would effectively be the end of physics, I assume because the fundamental physics underlying the string landscape is only accessible at scales/energies far beyond those accessible to any currently conceivable experiment. I can't quite see this, so perhaps someone could elaborate. That is, it seems to me unlikely that there is a theory that is going to say the ratio of electron to proton masses is exactly what it is (1:1836.15267245 or so, I believe) and that this emerges from simple principles. Since the proton is a composite particle a better example might be the ratio of the electron to muon masses, which I believe is around 1:206.7682821476077. When the chemical elements were being discovered, it became clear that there were simple principles underlying the apparently complexity. There were what seemed like completely different substances, which turned out to be related by simple numbers, e.g. if you take something like 2 grams of hydrogen and 16 grams of oxygen and mix them you get 18 grams of water. (Or whatever the correct figures are.) The point being that these small integer (or almost-integer, but they couldn't measure them accurately enough to realise that at the time) values indicate something simpler underlying the observed complexity, whereas 1:1836.15267245 or 1:206.7682821476077, it seems to me, don't. And so on for the various other dimensionless ratios that abound in the Standard Model, plus the fact that we see neutrinos with only one handedness, the absence of antimatter and various other apparent symmetry breakings This seems to me to indicate that a multiverse could easily be involved, and that the (ahem) string of apparently random values we observed emerge from something like there being 10^500 ways to knot a piece of string in 11 dimensions. What I don't understand is why this would not *also* allow supersymmetry to exist? Or why would SUSY rule out a multiverse, as the people in the film seemed to think? Or maybe I misunderstood them. Anyone out there with the ability to explain advanced physics to dummies? -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Interesting Google tech talk on QM

On Tue, Apr 29, 2014 at 3:02 PM, John Mikes jami...@gmail.com wrote: *Brent(?) wrote*: No I never read that, but hell yeah, MWI worries me! Doesn't it worry you? I mean I know at one level that in a very real sense it doesn't matter whether it's true or not, since the other universes can never affect me, but at another the reality that everything happens to me that I can imagine is just plain terrifying. And the 'me' isn't just the versions of me that are still called by my name, I can't escape the conclusion that I am everyone and everyone is me and that *everyone's* experience is my experience at some level. If MWI ever does become the accepted conception of reality, we have a huge amount of philosophical reorientation ahead of us. For instance, if I take some risk (like drink-driving, a relevant topic on another thread), and 'get away with it', MWI suggests I am still responsible for other realities in which I crashed and injured or killed myself and/or others. My whole approach to risk management becomes quite different if all outcomes are realised. In what ways would your approach to risk management need to change if there was still some notion of different outcomes having different measures that correspond to normal classical probabilities? In a MWI context you might have a scenario where you can say if I take action X, then I expect in 95% of worlds outcome Y will occur, but in 5% of worlds outcome Z will occur, but in what cases would your choice about whether to take outcome X be any different than a one-world scenario where you can say if I take action X, then I expect there's a 95% probability outcome Y will occur, but a 5% probability outcome Z will occur? Can you think of any specific examples where this would change your decision? The MWI advocate David Deutsch had a quote about choices and morality in the article at http://www.newscientist.com/article/mg17122994.400-taming-the-multiverse.htmlwhich made sense to me: By making good choices, doing the right thing, we thicken the stack of universes in which versions of us live reasonable lives. When you succeed, all the copies of you who made the same decision succeed too. What you do for the better increases the portion of the multiverse where good things happen. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Interesting Google tech talk on QM

On Tue, Apr 29, 2014 at 10:24 PM, Russell Standish li...@hpcoders.com.auwrote: On Tue, Apr 29, 2014 at 04:19:01PM -0400, Jesse Mazer wrote: The MWI advocate David Deutsch had a quote about choices and morality in the article at http://www.newscientist.com/article/mg17122994.400-taming-the-multiverse.htmlwhich made sense to me: By making good choices, doing the right thing, we thicken the stack of universes in which versions of us live reasonable lives. When you succeed, all the copies of you who made the same decision succeed too. What you do for the better increases the portion of the multiverse where good things happen. Jesse Makes no sense to me. You do not thicken the stack of universes, nor do you increase the portion of the multiverse where good things happen. The Multiverse just is - proportions do not change because of choices of inhabitants. I agree that we don't change the multiverse itself since the MWI is deterministic, but thicken and increase could just be taken as a comparison between those whose personalities and beliefs make them more likely to make good choices and those whose brains make them less likely. And given the power of habit, perhaps each good choice modifies your brain somewhat to make subsequent good choices more likely. If that's the case, then a good choice at decision point A thickens the stack of branches where you make further good choices about events BC that follow A, in comparison to the thinner stack of branches where your subsequent choices about BC were good after you made an immoral choice at A. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Interesting Google tech talk on QM

On Wed, Apr 23, 2014 at 7:08 AM, LizR lizj...@gmail.com wrote: On 23 April 2014 22:29, Telmo Menezes te...@telmomenezes.com wrote: Hi Liz, The billions make sense to me, to be honest. Even before the earth, we still didn't exist. It sounds like poetic liberty for a mind blowing amount of time. Sure, but I think at the time millions of years was a mind-blowing amount of time - actually it still is - and it would appear the comment doesn't have any known source. So although I'd be happily proved wrong on this, it just feels a bit anachronistic for Samuel Clemens. Maybe just my personal bias. The people at the snopes board did some looking around for the quote at http://message.snopes.com/showthread.php?t=81874 and couldn't find any appearances before 2002, so it's probably not a real quote. However, they did turn up the following quote from Twain's autobiography which the fake quote was probably a paraphrase of: Annihilation has no terrors for me, because I have already tried it before I was born—a hundred million years—and I have suffered more in an hour, in this life, than I remember to have suffered in the whole hundred million years put together. see http://harpers.org/blog/2008/03/no-terrors-for-me/ for confirmation. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: The situation at Fukushima appears to be deteriorating

On Fri, Mar 21, 2014 at 7:20 AM, Edgar L. Owen edgaro...@att.net wrote: Spud, But reducing human overpopulation IS the main problem facing the planet, the ecosystem, and the human species itself. Assuming that increasing technology will somehow solve the problem is, I fear, naive. It is precisely the use of more and more powerful technology that has resulted in the exponential destruction of the environment by the exponentially increasing number of humans. So it's not better technology we need, but the wisdom to use it sustainably Edgar Most demographers project that the population will level off at around 10 billion, because of various trends that tend to reduce the number of children like populations becoming more urban and women being more educated--see https://en.wikipedia.org/wiki/World_population#Projectionsfor some info. Of course predicting human behavior is never purely scientific and there are some who think this projection is too optimistic, see http://e360.yale.edu/feature/what_if_experts_are_wrong_on_world_population_growth/2444/ Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: The situation at Fukushima appears to be deteriorating

On Fri, Mar 21, 2014 at 12:19 PM, John Clark johnkcl...@gmail.com wrote: On Wed, Mar 19, 2014 at 10:50 AM, Quentin Anciaux allco...@gmail.comwrote: The thing I most want to know about RCP4.5 is what RCP stands for, Google seems to think it's Rich Client Platform but that doesn't sound quite right. It must be pretty obscure, Wikipedia has never heard of RCP either. For your information, that means Regional Climate Prediction I'm pretty sure it's not Russian Communist Party but are you sure it's not Representative Concentration Pathways? Wikipedia lists 21 possible meanings of the acronym RCP and that's the only one that has anything at all to do with the environment. Wikipedia has never heard of Regional Climate Prediction. http://en.wikipedia.org/wiki/RCP It seems you're correct here, the RCP4.5 scenario I discussed was one of four reprentative concentration pathway scenarios as indicated by the https://en.wikipedia.org/wiki/Representative_Concentration_Pathways wiki page. Of course, this doesn't change the fact that you chose to use a rhetorical question about the meaning of the acronym as a lame excuse to totally duck my point that it shows emissions being reduced in a non-drastic way but with a significantly better range of projected temperature rises by 2100 than the business-as-usual scenarios. But this was in keeping with your 100% non-substantive response which ducked every single issue I brought up, like the fact that plenty of people who want to take action on the climate are pro-nuclear (your only response was smartass-teenager style mockery of my use of the word strawman, ignoring the actual case I made that your characterization of environmentalist views was entirely cherry-picked and non-representative), or the fact that water vapor is not a climate forcing factor like CO2, or the question of what general standard you use to judge the merit of scientific claims in areas you have no expertise in (though your various ignorant claims about physics suggest your standard is something like treat scientific expertise as worthless whenever it doesn't match what I'd prefer to believe, and place unerring faith in whatever handwavey verbal analysis of a scientific question happens to pop into my head, arguing for this view with supreme confidence regardless of whether I can find any expert support for it). Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: The situation at Fukushima appears to be deteriorating

On Fri, Mar 21, 2014 at 12:59 PM, Telmo Menezes te...@telmomenezes.comwrote: On Fri, Mar 21, 2014 at 5:24 PM, Quentin Anciaux allco...@gmail.comwrote: 2014-03-21 17:19 GMT+01:00 John Clark johnkcl...@gmail.com: On Wed, Mar 19, 2014 at 10:50 AM, Quentin Anciaux allco...@gmail.comwrote: The thing I most want to know about RCP4.5 is what RCP stands for, Google seems to think it's Rich Client Platform but that doesn't sound quite right. It must be pretty obscure, Wikipedia has never heard of RCP either. For your information, that means Regional Climate Prediction I'm pretty sure it's not Russian Communist Party but are you sure it's not Representative Concentration Pathways? I'm pretty sure you must be dumb as dumb if you really think this... As I see we are in a thread talking about climate... This thread seems to be mostly about politics. To be fair, John seems to be in the minority here in wanting to discuss this from a scientific and technological perspective. Only if by discuss this from a scientific and technological perspective you mean cast vague aspersions at various scientific claims (use of climate models to predict future climates, analyze prehistoric glaciation thresholds, predict how climate would respond to specific GHG reduction scenarios like RCP4.5) and technical projections (like the specific plan to get 69% of electricity from solar by 2050), based on whatever verbal argument appeals to him and without any expert opinion of his own to cite in support of this skepticism. He raises a number of points that I have raised myself in previous discussions. Instead of focusing on such issues, pop culture distractions (Fox News etc.) and political tribalism seem to get all of the attention. I haven't talked about such political issues at all, although John seems to have plenty of enthusiasm for politically-based caricature of what environmentalists believe, based on cherry-picking the worst plans he can find trawling various websites rather than attempting any fair-minded survey of how many groups and prominent climate activists would agree with those plans. - Given the number of climate models and the fact that the majority of them failed to predict the climate of the last decade, how confident can we be in further predictions? Climate models predict that there should be plenty of statistical fluctuation on the level of individual decades, so this amount of uncertainty is already incorporated into the range of predictions made by an ensemble of such models. And current temperatures do still fall within the range predicted by models from earlier dates like 2000 and 1988. I addressed both the issue of how well models have done in their predictions and the issue of the 15-year warming pause (which climate scientists seem to think they understand the causes of fairly well) in this post: http://www.mail-archive.com/everything-list%40googlegroups.com/msg50488.html The page at http://grist.org/climate-energy/climate-models-are-unproven/(from the series of responses to common climate skeptic arguments at http://grist.org/series/skeptics/ ) also has a basic summary of some of the evidence supporting the reliability of climate models. More generally, I would repeat the general point that I think the only Bayesian prior when looking at scientific questions is assign a high a priori likelihood that experts in the field are correct when they broadly agree on the answer to some question, only revise that in light of changes in expert opinion, obvious failed predictions that don't line up with their theories, or acquiring enough expertise in the subject yourself to have an informed opinion on the detailed evidence. So if the experts in climate science are in broad agreement about climate models being reliable in the sense that actual temperatures will very likely fall within the *range* that they predict over many different runs (a statistical prediction rather than an exact one obviously), given the right emissions scenario, my default is to trust their judgment. To ignore expert opinion and think that you, as a layman, are just as qualified to draw conclusions about the reliability of models in *any* area of natural science seems to me to be a basically anti-scientific, anti-intellectual attitude. - With current technology, how much would we have to shrink the global energy budget to transition to sustainable sources? What would the human impact of that be? This is too serious an issue for wishful thinking. Theres 7 billion of us and counting. We need hard numbers here, that take into account the energy investment necessary to bootstrap the renewable sources, their efficiency and so on. The usual idea is not to significantly shrink the global energy budget (although some shrinkage may be possible without sacrificing living standards if we can find more energy-efficient ways of achieving the same goals, as with things like hybrid vehicles

### Re: Entropy and curved spacetime

On Fri, Mar 21, 2014 at 3:00 PM, John Clark johnkcl...@gmail.com wrote: On 18 Mar 2014, at 22:33, LizR wrote: Am I right in assuming that in a quantum mechanical universe you can trace the history backwards? Absolutely not because in Quantum mechanics 2 very different states can evolve into the exact same state. Not if you're just talking about the evolution of the quantum state vector according to the Schroedinger equation, which is totally deterministic. As I said to Liz, non-reversibility only appears if you assume the collapse of the wavefunction to a new quantum state on measurement is a real physical phenomenon distinct from normal wavefunction evolution, rather than an approximate description of something that happens due to decoherence (as would be true in the many-worlds interpretation where the universal state vector is all there is, and also in Bohm's hidden variables interpretation which is deterministic at all stages). Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Entropy and curved spacetime

On Fri, Mar 21, 2014 at 5:15 PM, Bruno Marchal marc...@ulb.ac.be wrote: On 21 Mar 2014, at 20:17, Jesse Mazer wrote: On Fri, Mar 21, 2014 at 3:00 PM, John Clark johnkcl...@gmail.com wrote: On 18 Mar 2014, at 22:33, LizR wrote: Am I right in assuming that in a quantum mechanical universe you can trace the history backwards? Absolutely not because in Quantum mechanics 2 very different states can evolve into the exact same state. Not if you're just talking about the evolution of the quantum state vector according to the Schroedinger equation, which is totally deterministic. Deterministic is compatible with the fact that 2 very different states can evolve into the exact same state, making it non reversible. But the solution of the SWE are more than deterministic, they are reversible. In QM (without collapse) 2 different states evolves into two different states. True. I spoke too quickly, I guess my mind jumped to determinism rather than reversibility (which is a type of reverse determinism) because I figured John was thinking of quantum randomness, which only enters in QM if you adopt the postulate of a random collapse on measurement. But John was correct in thinking that determinism does not entail reversibility. He gave the example of the game of life. But most arithmetical operations are like that too. 2+3 gives 5, but from 5 you can't necessarily retrieve 2+3, it might be 1+ 4 or 101 - 96. I agree with what you say, but I was actually the one who brought up the Game of Life in the discussion with John, because I was using it to make the point that the second law of thermodynamics is more than a tautology, that it actually depends on some specific properties of the laws of physics such as satisfying Liouville's theorem. With the appropriate choice of macrostates (namely, defining a macrostate by the ratio of live to dead cells), in the Game of Life the odds can favor a higher-entropy state evolving to a lower-entropy one (since if you start with a random 50:50 mix of live and dead cells, after enough time you are likely to end up in a state where most or all the cells are dead). Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: The situation at Fukushima appears to be deteriorating

On Thu, Mar 20, 2014 at 9:55 AM, spudboy...@aol.com wrote: Very well, go ahead and power it all down. Shut off the cars, kill the lights, take a bike. Are you suggesting that we continue to burn filthy coal, or horrible uranium, while we try to goose up solar and wind to replace it?!! Why that will take decades and the catastrophe is already upon us. The heating of the atmosphere and the degradation of the lands and seas, cannot wait (your guys tell us). No, nobody says it cannot wait and therefore we have to shut off all fossil fuel based power now, what some people say cannot wait is adopting some long-term plan that will transition away from fossil fuel gradually over several decades. I'm sure virtually all those concerned about global warming would be happy if we adopted any one of a number of plans which would end with a transition to majority-renewables by 2050, such as the ones below: http://www.sciencedirect.com/science/article/pii/S0301421508004072 (the solar grand plan I mentioned to you earlier which is summarized at http://web.chem.ucsb.edu/~feldwinn/greenworks/Readings/solar_grand_plan.pdf) http://www.nrel.gov/analysis/re_futures/ (articles summarizing this one at http://blogs.denverpost.com/thebalancesheet/2012/07/09/renewable-energy/5430/ and http://www.technologyreview.com/view/428284/the-us-could-run-on-80-percent-renewable-electricity-by-2050/ ) http://news.stanford.edu/news/2009/october19/jacobson-energy-study-102009.htmland http://news.stanford.edu/news/2014/february/fifty-states-renewables-022414.html(other articles discussing this plan at http://blogs.ei.columbia.edu/2013/07/30/charting-the-course-to-a-100-percent-renewable-energy-future/and http://theenergycollective.com/hermantrabish/352551/another-blueprint-100-percent-renewables-mid-centuryand a Scientific American summary by the authors at http://books.google.com/books?id=pGfQmBtXYx0Clpg=PP1pg=PT11) http://www.udel.edu/V2G/resources/BudischakEtAl-2013-CostMinimizedWindSolarPJM.pdf(discussed at http://www.greentechmedia.com/articles/read/how-about-99.9-percent-renewables) Or what are they really saying, put into motion in real life? It comes down to a culture of complaint from the green-reds, rather than actual workable solutions. I want technical solutions, but then, I am in the minority By technical solutions do you just mean technical plans laying out in detail how the transition to a renewable-dominated power grid would work, and how much it would cost? If so, see above. On the other hand, maybe you mean I'm waiting for some technological breakthrough that will make renewable energy so cost-effective that the free market will rush to abandon fossil fuels without the government having to lift a finger, until then we should do nothing to cut back on emissions even if it would be economically feasible. In that case, no that hasn't happened, but at least the plans above show that fearmongering about how trying to curb emissions would destroy the economy don't have any basis in fact. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Entropy and curved spacetime

Yes, if you have the exact present quantum state and you're assuming the normal quantum rules for continuous wavefunction evolution, you can determine the past quantum state. The answer might change if you assume that there's an objective physical reality to the collapse of wavefunction with measurement, distinct from the normal wavefunction evolution rules. Jesse On Tue, Mar 18, 2014 at 5:33 PM, LizR lizj...@gmail.com wrote: Am I right in assuming that in a quantum mechanical universe you can trace the history backwards? -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: The situation at Fukushima appears to be deteriorating

reductions goals the EU has set for itself (and they have successfully reduced emissions by 18% since 1990 when they set these goals, as I mentioned earlier). Proposals like a carbon tax and a carbon cap would be included in this, since the proposals involve starting with a tax/cap that wouldn't require any major immediate change in what fossil fuel companies are doing, and then gradually make it a tiny bit stricter each year over a period of decades. What do they want us to do, a rational person may ask (assuming we can find one)? The great booming word from environmentalists is conservation, followed by the sound of chirping crickets, yes, there's a few crickets still alive after massive species decimation. As I said to John Clark, no scientists really claim there has been a massive decimation of species (percentage-wise anyway) at present, the claim is that the RATE of extinction (percent of species going extinct PER YEAR) has shot up in recent years, and that if it continues at this rate for another century (or a few centuries depending on the estimate of the current rate) then we will have a true mass extinction. Jesse When the discussion turns from technology to government control, and the necessity for it as promoted by pols who cite scientists, my spider-sense becomes active. Yes, there a few spiders left after environmental degradation. -Original Message- From: Jesse Mazer laserma...@gmail.com To: everything-list everything-list@googlegroups.com Sent: Thu, Mar 13, 2014 12:47 am Subject: Re: The situation at Fukushima appears to be deteriorating On Wed, Mar 12, 2014 at 7:36 PM, spudboy...@aol.com wrote: My integrity is not the issue, Yes it is, since you made an error in your reading of the Royal Society/National Academy of Sciences paper, and instead of admitting the error you simply ignore the issue even when I repeatedly question you about it. for someone who states- *This all falls under gossipy political speculations about human motivations, I'm not interested in dragging this stuff into a conversation about natural science* Not sure what connection you think there is between this statement of mine and integrity. Would you respect my integrity more if I made up unfalsifiable fantasy narratives about the nefarious motives of conservatives and global warming deniers to counter your equally unfalsifiable fantasy narratives about the nefarious motives of liberals and environmentalists? Again, its science when its on your own terms, and it suits your ideology. Not at all, as I said to John Clark I treat it as the default position that whenever scientists in a field of natural science express confidence about ANY technical claim in their field, and there doesn't seem to be substantial disagreement among them, then my starting assumption is that they are most likely right about this claim (an assumption I would only be likely to change if I acquired enough knowledge the field to understand the detailed basis for the claims myself and find technical reasons to doubt them, or if I found out that some substantial number of other scientists disputed the claim). This is a blanket view of all natural science claims that has nothing to do with political ideology, for example I have no patience with the view (all too common among those on the left) that GMOs are a dangerous health risk since all the scientific experts I've seen say that extensive study has shown no more health risks from GMOs than from crops created through selective breeding. Anyone who does NOT adopt this blanket view of scientific claims is almost certainly filtering their evaluations of science through their personal ideology, and lacking respect for the importance of detailed technical understanding when evaluating scientific issues. I suspect your understanding of the detailed evidence behind many other scientific claims, like estimates of the age of the universe in cosmology, is just as poor as your understanding of the evidence surrounding global warming, but I imagine you don't put forth fantasy narratives of cosmologists peer-pressuring each other into accepting each other's models and wildly exaggerating the strength of the evidence for their theories, presumably because you have no ideological reason to dispute the idea that the Big Bang happened 13.75 billion years ago. Unless you are equally skeptical about *all* scientific claims whose technical basis you don't understand, you have a clear double standard--mistrust the scientists when their claims conflict with your ideology, but trust them when there is no such ideological conflict. Your nuclear energy remediation proposal will be violent opposed by your green chums, so it becomes, effectively, no answer. Certainly there are plenty of greens who oppose nuclear power (and examples like Fukushima show the risks are not to be scoffed at, although they are mainly

### Re: The situation at Fukushima appears to be deteriorating

On Wed, Mar 12, 2014 at 10:29 AM, John Clark johnkcl...@gmail.com wrote: On Tue, Mar 11, 2014 at 11:39 AM, Chris de Morsella cdemorse...@yahoo.com wrote: *On Behalf Of *LizR I must admit I've heard the extinction rate is way higher than usual - asteroid / methane burp high. (Although if it's us or them, as I said, that's a different story...) Liz - it is not hearsay [...] There is substantial, incontrovertible evidence that the extinction rate has literally spiked through the roof. That's not just hearsay it's idiotic. 66 million years ago 2/3 of all species, not individual animals but entire species, became extinct quite literally overnight, and 252 million years ago it was even worse, the extinction rate was 90%. What we're experiencing now is not even a burp. You fail to understand the distinction between the extinction RATE--percentage of species going extinct PER UNIT TIME--and the actual percentage of species that have gone extinct in total (akin to rate of travel in a car, i.e. speed, vs. total distance traveled). 90% is not a rate at all, it's a total. The argument is that the rate has gone way up from the background extinction rate in recent history, and if the rate REMAINS this high for another century or two, then the total percentage of species that go extinct will reach mass-extinction levels, even though it hasn't yet. Apparently there is some controversy about the current rate, see discussion of an optimistic paper by Costello et al. at http://www.sciencedaily.com/releases/2013/01/130124150806.htm along with the response from some other scientists at http://www.soc.hawaii.edu/mora/Publications/Mora%20036.pdf ...the response notes that the Costello et al. paper presents an estimate (0.001%-0.1% per year) that's very low compared with nearly all previous estimates, and that a previous paper by one of the coauthors of the optimistic paper, Nigel Stork, had compiled a number of estimates which together gave an average of 0.72% per year, and that Removing all rates derived from species-area relationships, which are currently debated [(12), but see (14)], still yields a mean extinction rate of ~0.22% or ~11,000 species a year if there are 5 million species. Fig. 1 gives some curves showing the TOTAL FRACTION of species that will have gone extinct in the next few centuries if the rates remain at either 0.72% per year (solid red curve) or 0.22% per year (dotted red curve), you can see that about half of all species would go extinct by 2100 if the rate was 0.72% per year, and about half would go extinct by 2300 if the rate was 0.22% per year. Either one would be a near-instantaneous mass extinction on geological timescales. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: The situation at Fukushima appears to be deteriorating

On Wed, Mar 12, 2014 at 2:52 PM, spudboy...@aol.com wrote: Autism, schmatism. Let me address this situation in concise terms, and if you want to discuss, we can discuss. But you refuse to discuss the Royal Academy/National Academy of Sciences paper, apparently (I take this as a sign that you probably recognize from my comments that you misread it, but don't have the intellectual integrity to admit when you've made an error). Here goes- 1. The models to date have not predicted successfully. Well, yes they have, for example the first graph in the article at http://www.realclimate.org/index.php/archives/2013/02/2012-updates-to-model-observation-comparions/shows what the CMIP3 dataset, which was based on collecting the predictions of a number of different climate models, predicted for 2000 on. The gray area shows the range in which 95% of the model simulations stayed within, and the black line is the average prediction of all the simulated runs, you can see that the actual climate as remained well within the gray area. Even simpler climate models going back as far as 1988 have proved pretty accurate, for example see the article at http://www.realclimate.org/index.php/archives/2007/05/hansens-1988-projections/about Hansen's 1988 temperature predictions using a number of different emissions scenarios--the first graph shows that actual emissions proved to be closest to the emissions scenario he labeled scenario B, and the second graph shows that the actual observed temperature up to 2007 (when the article was written), shown in red and black, hewed pretty closely to his predicted temperature for scenario B in blue. As for the recent pause in the warming trend over the last 15 years, this article has good discussion: http://www.realclimate.org/index.php/archives/2013/12/the-global-temperature-jigsaw/ One thing they note is that the models themselves predict pauses on those timescales should happen occasionally, as shown in a graph of one simulated run of a CMIP3 model in Fig. 2. They also note that the El Nino Southern Oscillation (ENSO) seems to be a major factor in the pause, along with some other factors like the recent low in solar activity and increased volcanic activity, and Fig 3 shows the data after adjusting for ENSO, volcanoes and solar activity by a multivariate correlation analysis--apparently when they attempt to subtract these recent changes out using some statistical techniques, the adjusted temperature in red would actually have been fairly steadily rising over the past 15 years. And here's another relevant article which discusses the growing consensus on the causes of the pause, saying A very consistent understanding is thus emerging of the coupled ocean and atmosphere dynamics that have caused the recent decadal-scale departure from the longer-term global warming trend: http://www.realclimate.org/index.php/archives/2014/02/going-with-the-wind/ I predict, however, that you will duck any detailed quantitative discussion of what the models predict since you only talk about science as an afterthought, you are mostly focused on gossipy political speculations about human motivations. 2. We have not as of this day, a technology to replace the dirty with the clean on energy. Nuclear power could certainly do it (although obviously that comes with its own risks distinct from global warming), and there's more than enough solar energy hitting the US to supply energy needs. Here's an article discussing a hypothetical proposal to supply *all* the U.S.'s energy needs with solar, with a price tag of about a trillion dollars (pricey obviously, but no more so than the Iraq war which didn't bankrupt us and probably wasn't a major cause of the recession): http://web.chem.ucsb.edu/~feldwinn/greenworks/Readings/solar_grand_plan.pdf 3. The elites of the world would be ordering thousands of dams/dikes all over the world, in order to save their own asses-if your IPCC guys were really true and, or, on time! 4. The elites are not behaving in this way, but they are declaring a disaster. If there's no disaster at hand, they are not building dams along the coastlines of the world, then I grow suspicious. 5. Apparently, many progressives/greens want to promote energy starvation, even though they have no technology, except their Amory Lovins type conservations crap from 25 years ago. 6. Which leads me to believe that because its cherry-picked data from scientists who would have no career if they didn't go along, it is the ideology of the progressives and the elites-mostly 1 in the same. This all falls under gossipy political speculations about human motivations, I'm not interested in dragging this stuff into a conversation about natural science (but it certainly supports my speculation that you are much more comfortable with obsessing about why people do the things they do than you are with discussing anything more impersonal like science and math). Jesse -- You received this

### Re: The situation at Fukushima appears to be deteriorating

On Wed, Mar 12, 2014 at 7:36 PM, spudboy...@aol.com wrote: My integrity is not the issue, Yes it is, since you made an error in your reading of the Royal Society/National Academy of Sciences paper, and instead of admitting the error you simply ignore the issue even when I repeatedly question you about it. for someone who states- *This all falls under gossipy political speculations about human motivations, I'm not interested in dragging this stuff into a conversation about natural science* Not sure what connection you think there is between this statement of mine and integrity. Would you respect my integrity more if I made up unfalsifiable fantasy narratives about the nefarious motives of conservatives and global warming deniers to counter your equally unfalsifiable fantasy narratives about the nefarious motives of liberals and environmentalists? Again, its science when its on your own terms, and it suits your ideology. Not at all, as I said to John Clark I treat it as the default position that whenever scientists in a field of natural science express confidence about ANY technical claim in their field, and there doesn't seem to be substantial disagreement among them, then my starting assumption is that they are most likely right about this claim (an assumption I would only be likely to change if I acquired enough knowledge the field to understand the detailed basis for the claims myself and find technical reasons to doubt them, or if I found out that some substantial number of other scientists disputed the claim). This is a blanket view of all natural science claims that has nothing to do with political ideology, for example I have no patience with the view (all too common among those on the left) that GMOs are a dangerous health risk since all the scientific experts I've seen say that extensive study has shown no more health risks from GMOs than from crops created through selective breeding. Anyone who does NOT adopt this blanket view of scientific claims is almost certainly filtering their evaluations of science through their personal ideology, and lacking respect for the importance of detailed technical understanding when evaluating scientific issues. I suspect your understanding of the detailed evidence behind many other scientific claims, like estimates of the age of the universe in cosmology, is just as poor as your understanding of the evidence surrounding global warming, but I imagine you don't put forth fantasy narratives of cosmologists peer-pressuring each other into accepting each other's models and wildly exaggerating the strength of the evidence for their theories, presumably because you have no ideological reason to dispute the idea that the Big Bang happened 13.75 billion years ago. Unless you are equally skeptical about *all* scientific claims whose technical basis you don't understand, you have a clear double standard--mistrust the scientists when their claims conflict with your ideology, but trust them when there is no such ideological conflict. Your nuclear energy remediation proposal will be violent opposed by your green chums, so it becomes, effectively, no answer. Certainly there are plenty of greens who oppose nuclear power (and examples like Fukushima show the risks are not to be scoffed at, although they are mainly risks to human health rather than environmental risks), but also plenty of greens who have come around to the view that nuclear power is a lesser evil when compared to fossil fuels, see for example this article that details many leading environmentalists who have become more nuclear-friendly (I suspect the number would be higher if we had thorium reactors, which should be significantly safer): http://www.washingtonpost.com/wp-dyn/content/article/2009/11/23/AR2009112303966.html Meanwhile, you completely ignored my point about it being well within the range of possibility to get all our energy from solar. I will prove your prediction correct with pure volition. I read the Nature realclimate link, article and my take away is its a struggle to try to figure out where the IPCC predictions went wrong? Was it el nino, heat sinks in the Pacific, etc. I'm glad you at least looked at it, but as with the Royal Society/National Academy of Sciences paper, your understanding of what you read seems to be quite poor (perhaps because you read with the attitude of looking for flaws rather than just trying to understand what's being argued). No one says the cooling is because of El Niño, but rather because La Niña has replaced El Niño for a while (part of a long-term cycle called 'pacific-decadal oscillation'), and the La Niña stage is thought to be ASSOCIATED WITH more heat being stored in the pacific, not a separate phenomenon that could be construed as a conflicting explanation. From the link at http://www.realclimate.org/index.php/archives/2013/12/the-global-temperature-jigsaw/-- Leading U.S. climatologist Kevin Trenberth has studied this for

### Re: The situation at Fukushima appears to be deteriorating

On Tue, Mar 11, 2014 at 12:33 PM, spudboy...@aol.com wrote: Thrre was a report judt last week released by the NAS and the UK Royal Society indicating that switching power sources will not help. You're just repeating yourself, did you actually read my response? I asked if you were talking about the report at http://dels.nas.edu/resources/static-assets/exec-office-other/climate-change-full.pdf, which was released by the Royal Society and NAS on Feb. 27 (I don't know if you'd call that last week)-- just tell me yes or no, please. If your answer is yes--and I'm pretty sure that the NAS and Royal Society didn't release any OTHER climate reports besides this one in the last couple weeks--then as I already explained before, it's clear you simply didn't understand it well (or didn't read the entire thing), since while the report did say on p. 22 that CO2 levels wouldn't drop quickly if emissions were halted, p. B8 also clearly shows that temperature wouldn't rise much beyond present levels in an aggressive emissions reduction scenario, whereas it would rise to levels that would likely be pretty catastrophic for human civilization in a business as usual emissions scenario. Secondly, the behavior of pols and the super rich are not consistent with this new report, or fears of an insurging ocean. Most politicians and super rich, like most people in general, have a bias towards preserving their near-term interests over long-term issues (especially issues that are only likely to become really serious after their death). The effects of climate change aren't fast enough that they're likely to have much effects on a politician's reelection prospects, or a rich person's stock portfolio over the next couple decades. Still, plenty of politicians and business leaders are making serious efforts, see this article I posted to John Clark about how the EU's emissions reduction policy has brought down emissions by 18% since 1990 levels, on track with the goals they set at the Kyoto conference: http://ec.europa.eu/clima/news/articles/news_2013100901_en.htm And here's an article about how Apple CEO Tim Cook shot down investors who didn't approve of the policy of reducing emissions by relying more on renewable energy: http://www.slate.com/blogs/the_slatest/2014/03/01/apple_ceo_tim_cook_shoots_down_global_warming_deniers_at_shareholders_meeting.html This peaks my suspicion. But fear not, I am but a submicron with zero influence on public policy. I just am suspicious of the ruling class using academic hucksters to glom more power-highly intelligent hucksters though they may be. So you think scientists are academic hucksters if they reach conclusions about objective reality that might favor policies that are inconvenient for your own political beliefs? Your responses to Chris clearly show you haven't made any attempt to understand the science on its own terms, independent of politics and crude us vs. them tribalistic thinking (liberals are worried about global warming while U.S. conservatives and libertarians typically aren't, liberals=bad, therefore it must be a power grab!) Jesse -Original Message- From: Jesse Mazer laserma...@gmail.com To: everything-list everything-list@googlegroups.com Sent: Mon, Mar 10, 2014 1:15 pm Subject: Re: The situation at Fukushima appears to be deteriorating On Mon, Mar 10, 2014 at 12:31 PM, lt;spudboy...@aol.comgt; wrote: According to Chris, Climate is not the weather or the local weather. So if this suggestion is correct, its local anomalies over the years, driven onward, by El Nino' or La Nina' ? According to a report released, last week, by the Royal Climate Group and the US national academy of sciences, a change in energy sources will not help us. I had to read it twice to comprehend what the report indicated. Are you talking about the report at http://dels.nas.edu/ resources/static-assets/exec-office-other/climate- change-full.pdf ? If so you have totally misunderstood what the report indicated, page B8 shows that climate models predict the Aggressive emissions reduction scenario would result in much lower global temperature in 2100 than the 'Business as usual' emissions scenario. They do say on p. 22 that If emissions of CO2 stopped altogether, it would take many thousands of years for atmospheric CO2 to return to 'pre-industrial' levels due to its very slow transfer to the deep ocean and ultimate burial in ocean sediments, but even if temperatures don't drop for a while, as long as they don't rise to levels much above what we have today, the consequences probably wouldn't be too bad (for a discussion of the likely consequences of each 1 degree rise, check out the book Six Degrees: Our Future on a Hotter Planet by Mark Lynas). Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email

### Re: The situation at Fukushima appears to be deteriorating

On Tue, Mar 11, 2014 at 1:50 PM, John Clark johnkcl...@gmail.com wrote: On Mon, Mar 10, 2014 at 3:58 PM, Jesse Mazer laserma...@gmail.com wrote: because before you initiate a policy that will impoverish the world for many generations and kill lots and lots and lots of people What policies are you talking about that would have these supposed effects? Shut down all nuclear reactors immediately. Stop using coal. Stop all dam construction and dismantle the ones already built. Stop all oil and gas fracking. Stop using geothermal energy. Drastically reduce oil production and place a huge tax on what little that is produced. Don't Build wind farms in places where they look ugly, reduce wind currents, kill birds or cause noise. Don't use insecticides. Don't use Genetically Modified Organisms. Don't use herbicides. Do exactly what the European Greens say. So, like a creationist you're unwilling to accurately depict the beliefs of those you disagree with, and instead you attack a boogeyman that has sprung mostly out of your own fevered imagination. There may be some radical environmentalists who believe these things, but the mainstream environmental groups (all the ones with any real influence) favor policies that will gradually scale back emissions without causing any abrupt changes in our living standards or power generation. The EU has been on track in their goals of emissions reductions, already cutting them by 18% from 1990 levels, And Germany alone spent 110 billion dollars to accomplish that, about $660 for every ton of CO2 they're cutting. And the net outcome of that staggering amount of money and effort is that by the end of this century global warming will be delayed by about 37 hours. Did you just made that number up? And why focus only on Germany, when the effects of the entire E.U.'s collective emissions reductions are presumably larger than those due solely to any individual country? Also, I brought this up to counter your wild claim that this would lead to economic depression and starvation--since it hasn't in the EU it presumably wouldn't in other countries like the U.S., and if the whole world (or even just the U.S.) followed the E.U.'s lead, do you deny that according to mainstream climate models, this would lead to significant temperature reduction from business as usual scenarios where no effort is made to curb emissions? Global warming is real and if it turns out to be a bad thing then we're going to have to fix it, but we need to do it in a smart way. When there is widespread expert consensus on how sure we should be about a scientific matter, and I have no expertise in the matter myself, I tend to assume as a default that the scientific experts likely have good grounds for believing what they do. Of course it's possible on occasion that expert consensus can turn out to be badly wrong but [...] There is consensus in the scientific community that things are slightly warmer now than they were a century ago, but there is most certainly NOT a consensus about how much hotter it will be a century from now, much less what to do about it or even if it's a bad thing. The study I linked to wasn't just about the fact that warming has occurred, it was specifically on the question of whether the recent warming is PRIMARILY CAUSED BY HUMAN ACTIVITIES, and it found that 97% of peer-reviewed papers that addressed the issue agreed with the consensus that it was. Obviously pretty much any scientist who agrees with this would also say that human emissions over the next century will have a large determining effect on the temperature in 2100. And note that the only way to reach such a consensus about the cause of past warming is if there is a consensus that climate models are broadly reliable in how they model the effects of various climate forcings like greenhouse gas emissions and solar input. Although there is plenty of range in what the models predict about temperatures in 2100 under any specific emissions scenario, if you look at a large number of models the likely temperature range goes up significantly under scenarios where we make no concerted effort to curb emissions vs. those where we do. I would say the precautionary principle applies here, if the higher ends of the likely range for a given emissions scenario are just as plausible as the lower ends, and if the higher ends of the likely range (or even both ends, under certain emissions scenarios) would be disastrous for human civilization, then we should make an effort to prevent that emissions scenario from becoming the reality. If anyone reading wants to know the actual ranges predicted by models (probably not John Clark, who will likely just make some vague comment about models being unreliable), the last IPCC report picked a number of possible future emissions scenarios and then applied a large number of different climate models to each one, the figure at http://www.climate-lab

### Re: The situation at Fukushima appears to be deteriorating

So, no response to my question about whether the paper I linked to was the one you were talking about, and my pointing out that p. B8 of the paper clearly indicates that it'll make a major difference to the temperature in 100 years whether we reduce emissions or carry on with business as usual? As for your comments, all I can say is that you seem to be one of those people who's only interested in thinking about issues in personal, narrative terms--us vs. them conceptions of which side supports a given position, speculations about the personal motivations people may have for taking the positions they do, etc. Discussion of more impersonal approaches to understanding the world, approaches based on math and quantitative evaluation of evidence, seems to be something you're entirely uninterested in. Sometimes I think we would have a much saner world if the average person was just, say, 5 points higher on the autism quotient scale ( http://www.wired.com/wired/archive/9.12/aqtest.html )... On Tue, Mar 11, 2014 at 2:48 PM, spudboy...@aol.com wrote: My point is Jesse, yes the truth is repeatable, is that the rich and their kept politicians, do behave in the short run, or as class-hero, John Maynard Keynes, said: in the long run, we're all dead. I maintain that their behavior is aligned with a great exaggeration, rather then a great dilemma. It's not like they do not partake the same bread with most of the media. Example, the NY Times is majority owned, by billionaire Carlos Slim Helu, and both Helu and pinchie Sulzberger, dine from identical world views. My view is that we are alive now, for a while, focus, then, on the issues, at hand. However, the rich and their pet pols know a good scheme when they see one. Or, as Henry Kissinger once noted, power is the greatest aphrodisiac. -Original Message- From: Jesse Mazer laserma...@gmail.com To: everything-list everything-list@googlegroups.com Sent: 11-Mar-2014 14:03:15 + Subject: Re: The situation at Fukushima appears to be deteriorating On Tue, Mar 11, 2014 at 12:33 PM, spudboy...@aol.com wrote: Thrre was a report judt last week released by the NAS and the UK Royal Society indicating that switching power sources will not help. You're just repeating yourself, did you actually read my response? I asked if you were talking about the report at http://dels.nas.edu/resources/static-assets/exec-office-other/climate-change-full.pdf, which was released by the Royal Society and NAS on Feb. 27 (I don't know if you'd call that last week)-- just tell me yes or no, please. If your answer is yes--and I'm pretty sure that the NAS and Royal Society didn't release any OTHER climate reports besides this one in the last couple weeks--then as I already explained before, it's clear you simply didn't understand it well (or didn't read the entire thing), since while the report did say on p. 22 that CO2 levels wouldn't drop quickly if emissions were halted, p. B8 also clearly shows that temperature wouldn't rise much beyond present levels in an aggressive emissions reduction scenario, whereas it would rise to levels that would likely be pretty catastrophic for human civilization in a business as usual emissions scenario. Secondly, the behavior of pols and the super rich are not consistent with this new report, or fears of an insurging ocean. Most politicians and super rich, like most people in general, have a bias towards preserving their near-term interests over long-term issues (especially issues that are only likely to become really serious after their death). The effects of climate change aren't fast enough that they're likely to have much effects on a politician's reelection prospects, or a rich person's stock portfolio over the next couple decades. Still, plenty of politicians and business leaders are making serious efforts, see this article I posted to John Clark about how the EU's emissions reduction policy has brought down emissions by 18% since 1990 levels, on track with the goals they set at the Kyoto conference: http://ec.europa.eu/clima/news/articles/news_2013100901_en.htm And here's an article about how Apple CEO Tim Cook shot down investors who didn't approve of the policy of reducing emissions by relying more on renewable energy: http://www.slate.com/blogs/the_slatest/2014/03/01/apple_ceo_tim_cook_shoots_down_global_warming_deniers_at_shareholders_meeting.html This peaks my suspicion. But fear not, I am but a submicron with zero influence on public policy. I just am suspicious of the ruling class using academic hucksters to glom more power-highly intelligent hucksters though they may be. So you think scientists are academic hucksters if they reach conclusions about objective reality that might favor policies that are inconvenient for your own political beliefs? Your responses to Chris clearly show you haven't made any attempt to understand the science on its own terms

### Re: The situation at Fukushima appears to be deteriorating

On Mon, Mar 10, 2014 at 12:31 PM, spudboy...@aol.com wrote: According to Chris, Climate is not the weather or the local weather. So if this suggestion is correct, its local anomalies over the years, driven onward, by El Nino' or La Nina' ? According to a report released, last week, by the Royal Climate Group and the US national academy of sciences, a change in energy sources will not help us. I had to read it twice to comprehend what the report indicated. Are you talking about the report at http://dels.nas.edu/resources/static-assets/exec-office-other/climate-change-full.pdf? If so you have totally misunderstood what the report indicated, page B8 shows that climate models predict the Aggressive emissions reduction scenario would result in much lower global temperature in 2100 than the 'Business as usual' emissions scenario. They do say on p. 22 that If emissions of CO2 stopped altogether, it would take many thousands of years for atmospheric CO2 to return to 'pre-industrial' levels due to its very slow transfer to the deep ocean and ultimate burial in ocean sediments, but even if temperatures don't drop for a while, as long as they don't rise to levels much above what we have today, the consequences probably wouldn't be too bad (for a discussion of the likely consequences of each 1 degree rise, check out the book Six Degrees: Our Future on a Hotter Planet by Mark Lynas). Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: The situation at Fukushima appears to be deteriorating

On Mon, Mar 10, 2014 at 1:52 PM, John Clark johnkcl...@gmail.com wrote: On Sun, Mar 9, 2014 at 2:47 PM, Jesse Mazer laserma...@gmail.com wrote: That looks like a pretty crappy match to me. What the hell happened 450 million years ago? And why did the CO2 start to drop 150 million years ago but the temperature start to climb at the same time? I suspect you are asking these questions not because you are genuinely curious, and have an open-minded attitude about the possibility that climate scientists might have reasonable answers, but [...] OK OK, I'm closed minded, stupid, enjoy bad environments and am in general am just a terrible human being; I never accused you of being stupid or enjoying bad environments. I do think, as our previous discussion on thermodynamics on the What are wavefunctions? thread showed (see my last refutation of your claims on that thread at https://groups.google.com/d/msg/everything-list/hJ9bNWqoAzI/QTrL0CopHJ8J ) that you seem to have an overly high opinion of your ability to make informed judgments about scientific ideas in areas that you clearly haven't studied on a technical level, a very common trait among those who attack mainstream science (creationists, people who think vaccines cause autism, people who don't think HIV causes AIDS, etc.). but my questions are still valid and deserve good answers Which I gave you. because before you initiate a policy that will impoverish the world for many generations and kill lots and lots and lots of people What policies are you talking about that would have these supposed effects? The EU has been on track in their goals of emissions reductions, already cutting them by 18% from 1990 levels, and I don't see them becoming impoverished or killing lots of their citizens, see http://ec.europa.eu/clima/news/articles/news_2013100901_en.htm you should be at least as sure of yourself as President Bush was that there were weapons of mass destruction in Iraq. Are you? When there is widespread expert consensus on how sure we should be about a scientific matter, and I have no expertise in the matter myself, I tend to assume as a default that the scientific experts likely have good grounds for believing what they do. Of course it's possible on occasion that expert consensus can turn out to be badly wrong, but if you look at the history of science in the post-Newtonian era (pre-Newton, it's harder to say what counts as science) this is actually very rare, and I can't think of any cases where the flaw in expert consensus was discovered by someone with no training in the subject themselves. So, given that the overwhelming majority of scientific papers discussing causes of the recent temperature rise agree that human activity is the main cause (97% of peer-reviewed papers according to the study at http://www.theguardian.com/environment/climate-consensus-97-per-cent/2013/may/16/climate-change-scienceofclimatechange) I take it as an operating assumption that this is very likely to be the objective reality. What policies we should take in response to that reality is another matter, but it's irrational to let the fact that you would rather not enact some proposed policies bias your beliefs about objective scientific matters (wishful thinking). Speaking of Bush and Iraq, given that we in the U.S. could spend over a trillion dollars on the Iraq war without bankrupting the country or leading to mass starvation (I don't think economists would say the crash of 2008 was caused in any direct way by this expenditure either), then it might be worth pointing out that it's been proposed that for about the same price (spread out over many years), the U.S. could convert to generating nearly all its power from solar: http://web.chem.ucsb.edu/~feldwinn/greenworks/Readings/solar_grand_plan.pdf On the question of what happened 450 million years ago in the Ordovician period, I googled Ordovician temperature and found a discussion of some scientific research at http://www.skepticalscience.com/CO2-levels-during-the-late-Ordovician.htmlwhich suggests there are at least some viable hypotheses about how the temperature drop could be explained in the framework of existing climate models: Hypotheses that answer scientific puzzles are a dime a dozen, hypotheses that correctly answer scientific puzzles are not. That's exactly the sort of vague response a creationist would give to being shown there are reasonable hypotheses about their own claimed puzzles. The point is, when you have a theory supported by a lot of evidence but some specific phenomena that fall under the theory aren't completely understood (like the causes of the Cambrian explosion in evolutionary history, or the evolutionary development of some organ whose fossil record is poor), if there are reasonable hypotheses about how the phenomena could be explained within the context of the theory, it's irrational to take a guilty until proven innocent stance where

### Re: The situation at Fukushima appears to be deteriorating

On Sun, Mar 9, 2014 at 1:34 PM, John Clark johnkcl...@gmail.com wrote: A black market degenerates into a cutthroat cartel True, but the blackness of the market has nothing to do with the nature of the commodity being transacted, it's black because somebody in government decided to make it black. Tobacco has killed many orders of magnitude more people than Meth and all other illegal drugs put together, but the market for tobacco is not black because somebody in government decided that particular drug is not illegal; so when tobacco deals go bad they don't machine gun each other, they sue each other. John, I repeat my question from earlier--if you disapprove of laws to make it illegal for people to make and sell drugs that lawmakers judge too damaging to society, do you also disapprove of laws to make it illegal for people to make and sell pharmaceutical drugs that some pharmaceutical company owns the patent for and wants to have exclusive rights to sell at a much higher cost than the cost of manufacture? Is the black market in drugs that violates pharmaceutical companies' intellectual property an example of the free market at work, or not? Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Block Universes

On Fri, Mar 7, 2014 at 8:37 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, I guess I'm supposed to take that as a yes? You do agree that A's world line is actually shorter than C's (even though it is depicted as longer) because A's proper time along it is less than C's from parting to meeting? Correct? Strange how resistant you are to ever saying you agree when we actually do agree. Remember we are not counting points here, at least I'm not, we are trying to find the truth I'm not resistant in general, I have said I agree to a number of agree/disagree questions you asked in the past. But in this one case I was expressing irritation because from your question it seemed pretty obvious you either hadn't read, or hadn't paid any attention to, my discussion of lengths in the post you were responding to. If you really, really can't deduce my opinion on this from statements like this: in terms of proper times C B A which is the opposite of how it works with spatial lengths or: in spatial terms a straight line is the SHORTEST path between two points, but in spacetime a straight (constant-velocity) worldline is the one with the LARGEST proper time between points ...then just tell me why you think these statements are ambiguous and I will then tell you whether I agree that A's world line is actually shorter than C's (even though it is depicted as longer) because A's proper time along it is less than C's from parting to meeting. But if reading those statements does answer your question, then I would suggest that part of trying to find the truth is actually reading through the responses you get, not skimming/skipping over parts of it. First, note you don't actually have to calculate anything. A and C just compare clocks when they meet and that gives the actual world line lengths. Sure, but I'm talking about the theoretical analysis. But, if you want to calculate to predict what that comparison will be, then you have to be careful to do it correctly. C can't just use the Pythagorean theorem on A's world line from his perspective on the x and y distances, he has to use it on the time dimension as well squareroot((y2-y1)^2 + (x2-x1)^2 - c(t2-t1)^2). You have the right idea, although that formula (with c^2 rather than c) actually calculates proper length on a spacelike interval, if you want proper time on a timelike interval the equivalent formula would be squareroot((t2-t1)^2 - (1/c)^2*(x2-x1)^2 - (1/c)^2*(y2-y1)^2). And since we were talking about a 2D spacetime diagram where all motion was along a single spatial axis, I dropped the y-coordinate, and as I mentioned I was also assuming units where c=1, like years for time and light-years for distance. That's why I just wrote the formula as sqrt((t2 - t1)^2 - (x2 - x1)^2). It is the subtraction of this time term that will reduce the length of the slanting blue lines of A and B to THEIR PROJECTIONS ON C'S OWN WORLDLINE. That statement appears wrong, although you'd have to give me a definition of what you mean by projections on C's own worldline for me to be sure. It seems to me that by the normal definition of projection, projecting one of the slanted blue line segments onto the C's vertical worldline would give a new segment parallel to the vertical axis, whose length is just equal to the vertical separation between the ends of the original slanted blue segment. If so, the length of that sort of projection is NOT equal to the proper time of the original slanted blue segment, instead it's equal to the coordinate time between its endpoints, in C's rest frame. For example, looking at the diagram at http://www.jessemazer.com/images/tripletparadox.jpg , let's say the bottom blue segment on A's worldline begins in 2001 in C's rest frame, and ends in 2008, and it has a velocity of 0.6c. In that case, by the normal meaning of projection, projecting this segment onto C's vertical worldline would just create a vertical segment that goes from 2001 to 2008, and thus has a coordinate time of 7 years (and for any vertical segment of a worldline parallel to the time coordinate axis, proper time is supposed to be equal to coordinate time). But because of time dilation, the proper time along the original blue segment (before it was projected to make it vertical) is less than the coordinate time by a factor of sqrt(1 - (0.8c/c)^2) = sqrt(1 - 0.64) = sqrt(0.36) = 0.6, so relativity says the correct proper time along that original slanted blue segment is 7*0.6 = 4.2 years. Do you agree or disagree with these numbers? I think that is what you are saying as well, but my point is that that NULLIFIES any effect on the length of the world lines by the SLANTING of the blue lines NO MATTER WHAT THEIR LENGTHS, and LEAVES ONLY the effects of the red curves. No, you're simply wrong about this. Let's actually do a numerical example. Suppose that both A and B go through the same sequence of 3 accelerations: ACCELERATION 1: starting from

### Re: Block Universes

On Sat, Mar 8, 2014 at 9:31 AM, Jesse Mazer laserma...@gmail.com wrote: And B's worldline consists of the following five segments: Segment 1 (blue): Remaining at rest in C's frame, from t=1999 to t=2009 Segment 2 (red): ACCELERATION 1 from t=2009 to t=2011 Segment 3 (blue): Moving inertially at 0.6c in the +x direction, from t=2011 to t=2013 Segment 4 (red): ACCELERATION 2 from t=2013 to t=2017 Segment 5 (blue): Moving inertially at 0.6c in the -x direction, from t=2017 to t=2019 Segment 6 (red): ACCELERATION 3 from t=2019 to t=2019 Correction--that last line for B's worldline should read Segment 6 (red): ACCELERATION 3 from t=2019 to t=2021 -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: The situation at Fukushima appears to be deteriorating

On Sat, Mar 8, 2014 at 1:56 AM, John Clark johnkcl...@gmail.com wrote: On Fri, Mar 7, 2014 at 9:09 PM, Chris de Morsella cdemorse...@yahoo.comwrote: Then who would ever want to live under a free market system if as you admit the transnational drug gangs are an exemplar of a well evolved free market? There is no disputing matters of taste so you could say if you wished that markets, and therefore people, shouldn't have too much freedom; but you can't say that the Black Market isn't a free market. There is a black market in pharmaceutical drugs as well as one in illegal drugs, would you say you can't say that the Black market isn't a free market in this case too? Or is the crime of violating a company's intellectual property rights sufficient to disqualify something from being a free market, unlike the crime of violating laws about what drugs are allowed to be used at all? Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Block Universes

On Sat, Mar 8, 2014 at 2:03 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, OK, Assume c=1 and start with your sqrt((t2 - t1)^2 - (x2 - x1)^2) to calculate what you say is the proper time on a time-like interval. Using your method, which I assume is correct I do see that A's proper time will be greater than B's. The reason is basically that A has to travel further in space to get from t1 to t2 and consequently must also travel less far in time. Correct? It's true in C's rest frame that A travels a greater distance than B, but this needn't be true if you used a different frame. For example, if you analyze the problem using an inertial frame D in which A is at rest during the first blue leg of his trip, then A and B should travel the same distance between departing and reuniting, because neither ever turns around and travels in the wrong direction in this frame, they are both always at rest in this frame or traveling in the -x direction towards the position in this frame where they will reunite. So if you imagine that A and B are cars that are driving along a piece of flat ground at rest in frame D, and both start out with odometers reading 0 when A first departs from B, then A and B's odometer will show the same reading when they reunite, since they have both traveled in a consistent direction (but varying speed) along the same straight road between the position in frame D where they departed and the position where they reunited. To confirm, consider a simplified twin example with only straight lines so we can ignore accelerations. A remains at rest with a straight vertical line from t1 to t3. B travels away from t1 in a straight oblique line, reverses direction midpoint (call this t2) and travels in a straight oblique line back to t3. The two halves of B's trip are symmetric (have the same velocities away from and back towards A) therefore B's proper time, calculated by A, will be = 2 x sqrt((t2 - t1)^2 - (x2 - x1)^2). In other words we have to multiply by 2 to get the proper time of B for the entire trip. Correct? Yes, that's correct. OK, now consider another case with A and B just moving with constant relative motion and their world lines crossing at t1 and then diverging. There is NO acceleration. In this case using the Lorentz transform both A and B will observe each other's time running slow relative to their own. And using your formula above both A and B will also observe each other's proper times SLOWED RELATIVE TO THEIR OWN. But doesn't this mean that since A and B get different results about each other's proper times that this method of calculating proper times is NOT INVARIANT, and thus is not actually calculating proper times which you say are invariant? The method gives an invariant answer for the proper time between any two specific events on an inertial worldline, events which are known to have coordinates (x1,t1) and (x2,t2) in whatever frame you're using. But in your example, they haven't agreed on a specific pair of points on each worldline to calculate the proper time between. Suppose their worldlines cross at the moment of their births, when they are both 0 years old, and subsequently they move apart with arelative velocity of 0.6c so the time dilation factor is 0.8c. If A wants to use his own rest frame to predict how old B will be at the same moment that A turns 20, he is picking the event b1 on B's worldline that is SIMULTANEOUS IN A's REST FRAME with A turning 20, and calculate the proper time between the event of B's birth and b1, which is 16. On the other hand, if B wants to use his own rest frame to predict how old he'll be at the same moment that A turns 20, he must pick the event b2 on B's worldline that is SIMULTANEOUS IN B'S REST FRAME with A turning 20, and calculate the proper time between B's birth and b2, which is 25. Both frames agree that the proper time between B's birth and b1 is 16, and that the proper time between B's birth and b2 is 25, they just disagree about whether b1 or b2 is simultaneous with A turning 20. So that's why they disagree about whether A is older or younger than B at any specified point on A's worldline, like A turning 20 (and of course the logic works the same if you specify a point on B's worldline and ask about A's age at the same moment). Of course, this sort of ambiguity about what events to choose doesn't arise in a twin-paradox type scenario where the twins depart from each other at one specific point on their worldlines, and reunite at some other specific point on their worldlines. If you want further evidence that the method gives an invariant answer, you can use the Lorentz transformation to check that this is so. Pick two events on the worldline of an inertial clock of arbitrary velocity in the frame you're using, and assume that the spacetime origin is chosen so that the first event is labeled with coordinates x1=0, t1=0. Then the second event can be anything (so long as the

### Re: Block Universes

On Sat, Mar 8, 2014 at 3:11 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, PS: And in your nice long numerical example, which I thank you for, it seems to me what you are doing is calculating the proper time length of every segment of A's trip in terms of C's proper time. Isn't that correct? No, it's in terms of coordinate time in C's rest frame. C's proper time can only be defined between pairs of events on C's own worldline. Of course if C is inertial as in this example, then the coordinate time of events on C's worldline is the same as the proper time between those events, but it doesn't make sense to talk about C's proper time between events that are NOT on C's worldline. But if so aren't you in fact establishing a 1:1 correlation of proper times between A and C with your method? And isn't that what you keep telling me CAN'T BE DONE? You can of course define a correlation in proper times of separated clocks A and B if you specify what frame's definition of simultaneity you want to use. Then you can find a pair of events a1 and b1 that are simultaneous in this frame, and a pair of events a2 and b2 that are simultaneous in this frame, and compare the proper time on A's worldline between a1 and a2 with the proper time on B's worldline between b1 and b2. But this sort of correlation will differ depending on what frame you choose (because the simultaneous events will differ), and what can't be done is find any basis in relativity for saying that one frame's correlation represents the real correlation while other frames' do not. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Block Universes

On Fri, Mar 7, 2014 at 4:02 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Finally hopefully getting a minute to respond to at least some of your posts. I'm looking at the two 2 world line diagram on your website and I would argue that the world lines of A and B are exactly the SAME LENGTH due to the identical accelerations of A and B rather than different lengths as you claim. The length of a world line is the PROPER TIME along that world line. Thus the length of a world line is INVARIANT. It is the length of the world line according to its proper clock and NOT the length according to C's clock which is what this diagram shows. I don't understand what you mean by the length according to C's clock--are you just talking about the numbers on the vertical time axis, 2000-2020? That axis represents the coordinate time in C's rest frame, and obviously the coordinate time between 2000 at the bottom of the diagram and 2020 at the top is 20 years regardless of what path you're talking about, so I don't see how it makes sense to call this the length of any particular path. But you can also use C's rest frame to assign x and t coordinates to the endpoints of any straight blue segment, x1 and t1 for one endpoint and x2 and t2 for the other, and then C can calculate the proper time along that segment as squareroot[(t2 - t1)^2 - (x2 - x1)^2] and get the correct INVARIANT answer (note that I am using units of light-years and years where c=1 so it doesn't appear in the equation, otherwise the second term in the square root would have to be (1/c^2)*(x2 - x1)^2). What the diagram is trying to show is that even though the different paths have identical red acceleration curves, they have different SPATIAL lengths, i.e. the length you'd measure if you printed out the diagram and laid a flexible cloth tape measure along each path to measure the distance ALONG THE PATH between the point at the bottom of the diagram where the paths diverge and the point at the top where they rejoin. It is true that if you just look at the spatial lengths of each path on the diagram, the ratio between the spatial lengths doesn't actually match up with the ratio between the proper times that would be calculated using relativity. If you use any Cartesian spatial coordinate system to draw x-y axes on the diagram, then you can use this coordinate system to assign x and y coordinates to the endpoints of any straight blue segment, x1 and y1 for one endpoint and x2 and y2 for the other, and then calculate the spatial length of that segment using the Pythagorean theorem: squareroot[(y2 - y1)^2 + (x2 - x1)^2]. Note that you ADD the squares of the two terms in parentheses when calculating spatial length, but my earlier equation showed that you SUBTRACT the square of the two terms in parentheses when calculating proper time, which explains why this sort of spatial path length on a spacetime diagram can be misleading. For example, in spatial terms a straight line is the SHORTEST path between two points, but in spacetime a straight (constant-velocity) worldline is the one with the LARGEST proper time between points. Nevertheless, the math for calculating the invariant spatial path length using a Cartesian coordinate system is closely analogous to the math for calculating the invariant proper time using an inertial frame. The diagrams show the spatial length of the paths being different despite identical red acceleration segments, and this remains true if you actually calculate proper time, even though in terms of proper times C B A which is the opposite of how it works with spatial lengths. If you assign time coordinates to the beginning and end of each acceleration phase, and you specify the proper acceleration involved, then you can calculate the proper time along elapsed on each worldline during both the acceleration phases (using the relativistic rocket equations given at http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html ) as well as the proper time during the constant-velocity phases (using the method I mentioned above with squareroot[(t2 - t1)^2 - (x2 - x1)^2] for each segment). If you do this, you do find that in a detailed numerical version of the scenario in the diagram, A ELAPSES LESS TOTAL PROPER TIME THAN B DESPITE HAVING IDENTICAL ACCELERATIONS. I can give the detailed calculations using the relativistic rocket equations if you want, or you can just take my word for it. So to calculate the length of A's and B's world lines in C's frame (which this diagram represents) we must take the apparent lengths as shown from C's frame view on the diagram, and SHORTEN each section by the apparent slowing of ITS CLOCK relative to C's CLOCK. Yes, that would be another way to calculate proper time along the blue constant-velocity segments: just take the times t2 and t1 of the beginning and end of each segment in C's frame, and multiply by the time dilation factor which depends on the speed v in C's frame during

### Re: Block Universes

On Fri, Mar 7, 2014 at 7:20 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Do you understand why the world line that is depicted as LONGER in the typical world line diagram is ACTUALLY SHORTER? E.g. in your diagram do you understand why even though A's world line looks longer than C's world line, it is ACTUALLY SHORTER? Edgar Are you actually reading my posts carefully all the way through, or just skimming them or something? I spent a whole extended section of my post discussing just this point, read it again: 'It is true that if you just look at the spatial lengths of each path on the diagram, the ratio between the spatial lengths doesn't actually match up with the ratio between the proper times that would be calculated using relativity. If you use any Cartesian spatial coordinate system to draw x-y axes on the diagram, then you can use this coordinate system to assign x and y coordinates to the endpoints of any straight blue segment, x1 and y1 for one endpoint and x2 and y2 for the other, and then calculate the spatial length of that segment using the Pythagorean theorem: squareroot[(y2 - y1)^2 + (x2 - x1)^2]. Note that you ADD the squares of the two terms in parentheses when calculating spatial length, but my earlier equation showed that you SUBTRACT the square of the two terms in parentheses when calculating proper time, which explains why this sort of spatial path length on a spacetime diagram can be misleading. For example, in spatial terms a straight line is the SHORTEST path between two points, but in spacetime a straight (constant-velocity) worldline is the one with the LARGEST proper time between points. Nevertheless, the math for calculating the invariant spatial path length using a Cartesian coordinate system is closely analogous to the math for calculating the invariant proper time using an inertial frame. The diagrams show the spatial length of the paths being different despite identical red acceleration segments, and this remains true if you actually calculate proper time, even though in terms of proper times C B A which is the opposite of how it works with spatial lengths.' On Friday, March 7, 2014 5:15:57 PM UTC-5, jessem wrote: On Fri, Mar 7, 2014 at 4:02 PM, Edgar L. Owen edga...@att.net wrote: Jesse, Finally hopefully getting a minute to respond to at least some of your posts. I'm looking at the two 2 world line diagram on your website and I would argue that the world lines of A and B are exactly the SAME LENGTH due to the identical accelerations of A and B rather than different lengths as you claim. The length of a world line is the PROPER TIME along that world line. Thus the length of a world line is INVARIANT. It is the length of the world line according to its proper clock and NOT the length according to C's clock which is what this diagram shows. I don't understand what you mean by the length according to C's clock--are you just talking about the numbers on the vertical time axis, 2000-2020? That axis represents the coordinate time in C's rest frame, and obviously the coordinate time between 2000 at the bottom of the diagram and 2020 at the top is 20 years regardless of what path you're talking about, so I don't see how it makes sense to call this the length of any particular path. But you can also use C's ... -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Block Universes

On Thu, Mar 6, 2014 at 11:02 AM, Edgar L. Owen edgaro...@att.net wrote: Liz, Sure, but aren't the different lengths of world lines due only to acceleration and gravitational effects? So aren't you saying the same thing I was? Isn't that correct my little Trollette? (Note I wouldn't have included this except in response to your own Troll obsession.) Anyway let's please put our Troll references aside and give me an honest scientific answer for a change if you can... OK? It would be nice to get an answer from Brent or Jesse as well if they care to chime in.. In the case of the traditional twin paradox where one accelerates between meetings while the other does not, the one that accelerates always has the greater path length through spacetime, so in this case they are logically equivalent. But you can have a case in SR (no gravity) where two observers have identical accelerations (i.e. each acceleration lasts the same interval of proper time and involves the same proper acceleration throughout this interval), but because different proper times elapse *between* these accelerations, they end up with worldlines with different path lengths between their meetings (and thus different elapsed aging)...in an online discussion a while ago someone drew a diagram of such a case that I saved on my website: http://www.jessemazer.com/images/tripletparadox.jpg In this example A and B have identical red acceleration phases, but A will have aged less than B when they reunite (you can ignore the worldline of C, who is inertial and naturally ages more than either of them). You can also have cases in SR where twin A accelerates more than B (defined in terms of the amount of proper time spent accelerating, or the value of the proper acceleration experienced during this time, or both), but B has aged less than A when they reunite, rather than vice versa. As always the correct aging is calculated by looking at the overall path through spacetime in some coordinate system, and calculating its length (proper time) with an equation that's analogous to the one you'd use to calculate the spatial length of a path on a 2D plane. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Thu, Mar 6, 2014 at 11:32 AM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Yes, from the point any two observers in the same inertial frame synchronize clocks, their clocks will be synchronized in p-time BUT ONLY FROM THEN ON (we can't know if they were previously synchronized unless we know their acceleration histories). And only SO LONG AS they continue in the same inertial frame OR undergo symmetric accelerations. Same ages is just a way to ensure synchronized clocks at the birth event and make examples simpler. It has nothing to do with p-time synchrony per se. So in your next paragraph your and Jimbo's proper clocks ARE synchronized in p-time from then on under the conditions stated. But I don't understand the rest of your example since you just stated that we are to ignore their PREVIOUS and SUBSEQUENT acceleration histories to preserve the synchronies but then you start giving an example with accelerations, which will obviously change their synchrony UNLESS they are symmetric. I clearly stated that the reason I was giving an example of accelerations was in case you DIDN'T accept the clocks were synchronized in p-time in my example with Jimbo, which ignored my and Jimbo's past acceleration histories and ages. My words were: OK, I don't think it should be necessary to specify acceleration histories or ages if you agree with my statement about me and Jimbo above, but if you disagree with that statement I can give details about each pair's past history, though it makes the example a bit more complicated. Since you do accept my statement about p-time simultaneity in the Jimbo example, then there's really no NEED to assume anything about A/B and C/D's past accelerations being symmetric, we can just assume that at some point before the experiment happened, A and B came to rest in frame F and synchronized their clocks in frame F, and C and D came to rest in frame F' and synchronized their clocks in frame F', and subsequently their x(t) and T(t) functions in frame F were as I described. However, in the rest of your post you are responding to my example of a history where A and B had symmetrical accelerations before the experiment, and so did C and D, so I will discuss that example; maybe it makes the statements about p-time simultaneity conceptually clearer to think of their history that way, although if you think it'd be simpler I'd also be just as happy to make the assumption above that each pair synchronized clocks after they came to rest in the same frame. You seem to claim that the accelerations are symmetric but you keep describing them as stopping in different frames at different times which indicates they are NOT symmetric. In my example both accelerations were totally symmetric in the frames where the twins started out at rest next to each other with synchronized clocks. A and B's accelerations were totally symmetric in the unprimed frame F where they started out both at rest at position x=12.5, and C and D's accelerations were totally symmetric in the primed frame F' where they started out both at rest at position x'=7.5. Of course since C and D stopped accelerating simultaneously in the primed frame F' (at time t'=-12 in F'), they stopped accelerating at different times in the unprimed frame F which I had used to describe their x(t) and T(t) functions, but surely your criteria for symmetrical accelerations is just that there is ONE specific frame where all their proper accelerations are simultaneous, namely the frame where they started out at rest and next to each other with synchronized clocks? Assuming that's your criteria, then F' is that one specific frame for C and D (and note that according to relativity, C and D's proper times T also remain synchronized in frame F' at all coordinate times), and F is that one specific frame for A and B (and A and B's proper times T also remain synchronized in F at all coordinate times). The only way to ensure the accelerations are symmetric is for both A and B to have the same proper accelerations at the same proper times AFTER they synchronize clocks. Are you doing that? If not you are not using MY method. Yes, I was doing that. In my example I said that in the unprimed frame F, A and B were originally at rest at position x=12.5, with both having the same ages, and let's say that their proper time clocks have been set to read T = -18 years at the moment they were born. Since they were right next to each other with the same ages and their proper time clocks both showing a time that's just their age minus 18, naturally their clocks were originally synchronized. Then they accelerated in a completely symmetrical way in frame F, with all changes in acceleration being simultaneous in F, including the event of their both ceasing their acceleration and coming to rest again in F, which happened at t=-12 in F. Also you seem to be switching from synchronized proper clocks which I assumed did NOT reflect actual ages

### Re: Block Universes

Just realized in retrospect that it was a very confusing choice of terminology to use reference frame to refer to the frame that's used to label other frame's relative velocities--I was thinking of the idea that other frame's velocities are labeled in reference to this one choice of frame, but somehow it didn't occur to me that reference frame is a synonym for frame of reference, which is what ALL frames are called. So I edited my post below to use the term index frame instead, since I'm indexing other frames by their velocity relative to this frame: On Thu, Mar 6, 2014 at 12:51 PM, Jesse Mazer laserma...@gmail.com wrote: I don't know what you mean by the frame view of all frame views. I agree that for a given pair of clocks A and B that are at rest relative to each other and synchronized in their rest frame, each frame has only ONE answer to how much clock A is ahead of B (a number which can be zero if the frame in question is their rest frame, and can also be negative if the frame in question sees clock A as having a time that's behind clock B's time). But if we want to LABEL each such frame by velocity (so we can do an integral or sum over frames with different velocities to take the average), then we must use some specific index frame, and label the velocity of every other frame relative to the index frame. So for example if a given frame X has a velocity of 0.9c relative to a pair of clocks that are 2 light-year apart in their own rest frame, then in X they are out-of-sync by 2*0.9 = 1.8 years. If we use as our index frame the rest frame of the clocks themselves, then X is labeled with v=0.9c since that's its velocity relative to the index frame, and thus our amount out of sync as a function of v function will have a value of 1.8 at v=0.9c. On the other hand, if we use as our index frame a frame moving at 0.8c relative to the clocks, then frame X will have to be labeled with v=0.357c since that's its velocity relative to the new index frame--it's still the same frame X, and it still has the same amount-out-of-sync of 1.8, but it just has a different velocity label. So using this index frame, our amount out of sync as a function of v function will have a value of 1.8 at v=0.357c. Point is, depending on the index frame we use to define the v of every other frame, our amount out of sync as a function of v function will look different, and thus if we integrate over that function to find some sort of average value for the amount the clocks are out of sync, or just do an average over a finite number of values of the function at regular intervals of v, then we'll get different answers depending on what index frame we chose. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.

### Re: Block Universes

On Wed, Mar 5, 2014 at 8:19 AM, Edgar L. Owen edgaro...@att.net wrote: Jesse, First I see no conclusion that demonstrates INtransitivity here or any contradiction that I asked for. Did I miss that? No, I was just asking if you agreed with those two steps, which show that different pairs of readings are simultaneous using ASSUMPTION 2. If you agreed with those, I would show that several further pairs of readings must also be judged simultaneous in p-time using ASSUMPTION 1, and then all these individual simultaneity judgments would together lead to a contradiction via the transitivity assumption, ASSUMPTION 3. I already laid this out in the original Alice/Bob/Arlene/Bart post, but since you apparently didn't understand that post I wanted to go over everything more carefully with the exact x(t) and T(t) functions given, and every point about simultaneity stated more carefully. I thought you would be more likely to answer if I just gave you two statements to look over and verify rather than a large collection of them, but if you are going to stubbornly refuse to answer the opening questions until I lay out the whole argument, here it is in full: ASSUMPTION 1. If two observers are at rest in the same inertial frame, then events on their worldlines that are simultaneous in their rest frame are also simultaneous in p-time ASSUMPTION 2. If two observers cross paths at a single point in spacetime P, and observer #1's proper time at P is T1 while observer #2's proper time at P is T2, then the event of observer #1's clock showing T1 is simultaneous in p-time with the event of observer #2's clock showing T2. ASSUMPTION 3. p-time simultaneity is transitive Please have another look at the specific numbers I gave for x(t), coordinate position as a function of coordinate time, and T(t), proper time as a function of coordinate time, for each observer (expressed using the inertial frame where A and B are at rest, and C and D are moving at 0.8c), and then tell me if you agree or disagree with the following two statements: For A: x(t) = 25, T(t) = t For B: x(t) = 0, T(t) = t For C: x(t) = 0.8c * t, T(t) = 0.6*t For D: x(t) = [0.8c * t] + 9, T(t) = 0.6*t - 12 STATEMENT 1. Given the x(t) functions for B and C, we can see that they both pass through the point in spacetime with coordinates x=0, t=0. Given their T(t) functions, we can see that B has a proper time T=0 at those coordinates, and C also has a proper time T=0 at those coordinates. Therefore, by ASSUMPTION 2 above, the event of B's proper time clock reading T=0 is simultaneous in p-time with the event of C's proper time clock reading T=0. Agree or disagree? STATEMENT 2. Given the x(t) functions for A and D, we can see that they both pass through the point in spacetime with coordinates x=25, t=20. Given their T(t) functions, we can see that A has a proper time T=20 at those coordinates, and D has a proper time T=0 at those coordinates. Therefore, by ASSUMPTION 2 above, the event of A's proper time clock reading T=20 is simultaneous in p-time with the event of D's proper time clock reading T=0. Agree or disagree? STATEMENT 3. At t=0 in this frame, both A and B have a proper time of T=0; these readings are simultaneous in this frame. Since A and B are both at rest in this frame, by ASSUMPTION 1 above, the event of A's proper time clock reading T=0 is simultaneous in p-time with the event of B's proper time clock reading T=0. Agree or disagree? STATEMENT 4. C's worldline passes through the point x=0, t=0, and at this point C's proper time clock reads T=0. D's worldline passes through the point x=25, t=20, and at this point D's proper time clock reads T=0. These events are not simultaneous in this frame, but using the Lorentz transformation we can see that they ARE simultaneous in the frame where C and D are at rest. Therefore, by ASSUMPTION 1 above, the event of C's proper time clock reading T=0 is simultaneous in p-time with the event of D's proper time clock reading T=0. Agree or disagree? Note: This statement is perhaps the subtlest if you aren't too familiar with the math of SR--in case you didn't know, the Lorentz transformation is used when we know the coordinates x,t of an event in one inertial frame, and we want to find the coordinates x',t' of the SAME event in a second inertial frame which is moving at speed v relative to the first (a good intro to various aspects of SR including the Lorentz transform can be found at http://en.wikibooks.org/wiki/Special_Relativity ). Assuming that the spatial origins of the two frames coincide when t=0 in the first frame and t'=0 in the second, and assuming that the first frame subsequently sees the origin of the second frame moving at speed v along the first frame's x-axis, the transformation equations are: x' = gamma*(x - v*t) t' = gamma*(t - (v*x)/c^2 ) Where gamma is the commonly-used relativistic factor 1/sqrt(1 - (v/c)^2). So with v=0.8c in this example, gamma works out to 1/sqrt(1 - 0.64) =

### Re: Block Universes

On Wed, Mar 5, 2014 at 8:38 AM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Here's another point for you to ponder: You claim that all frame views are equally valid. What would you say the weighted mean of all frame views is? Weighted how? I can't see any weighing that doesn't itself depend on privileging one frame over others. For example, suppose I label frames using velocity relative to my rest frame, and use a uniform distribution on velocity values as my weight function, which implies that the collection of frames with velocities between 0.1c and 0.1c + dV will have the same total weight as the collection of frames with velocities between 0.9c and 0.9c + dV, since these are equal-sized velocity intervals (for example, if dV=0.05c then we are looking at the frames from 0.1c to 0.15c, and the frames from 0.9c to 0.95c). But if we look at all the frames in these two intervals, and translate from their velocities relative to ME to their velocities relative to another frame B that is moving at say 0.8c relative to me, then these two bunches of frames do NOT occupy equal-sized velocity intervals when we look at their velocities relative to frame B (an interval from 0.1c to 0.15c in my frame translates to the interval from -0.761c to -0.739c in B's frame, while an interval of 0.9c to 0.95c in my frame translates to an interval from 0.357c to 0.625c in B's frame). So if we weigh them equally using MY velocity labels, that would translate to an unequal weighing relative to B's velocity labels, so we are privileging my frame's definitions over the definitions of other frames like B. I would suspect that it converges towards my solution. It is clear from your own analysis that it does converge to my solution as separation and relative motion diminishes, so I strongly suspect it converges towards my solution in all cases. Correct? And if so I would argue that this also tends to validate my solution as the actual correct 1:1 correlation of proper ages, even though I agree completely that all observers cannot direct observe this correlation... In fact this is tantalizingly similar to the notion of a wavefunction representing the probabilities of all possible locations of a particle. If we take all possible frame views as a continuous 'wavefunction' of the actual age correlation can we begin to assign probabilities based on their weighted mean, and if so isn't that going to be my solution? This doesn't really help your case unless you can find a weight function for the continuous infinity of different possible frames that doesn't itself privilege one frame's definitions from the start. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Wed, Mar 5, 2014 at 1:27 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Yes, you are right. I phrased it incorrectly. What I meant to say was not that each individual view was somehow weighted, but that all views considered together would tend to cluster around my results for any distance and motion difference pairs. Too vague. What does all views considered together mean mathematically, if not a weighted average using some specific weighting function? In other words there would be a lot more views that were close to my solution, than views that were far from my solution. How do you count more when there are a continuous infinity of frame's views? The only way to count different subsets of an infinite set is using some sort of measure function (see https://en.wikipedia.org/wiki/Measure_(mathematics) ), which is equivalent to a weighting function--whatever you choose to call it, the idea would be that if you want to compare the number or weight of frames with velocity between v1 and v2 (the velocities defined relative to some other specific frame, of course) vs. the number or weight with velocity between v3 and v4, you use a measure/weight function W(v) which gives a value for every specific frame velocity v, and you integrate the function W(v) from v1 to v2, and compare the result to integrating W(v) between v3 and v4 (and if you want to do a weighted average of some specific quantity Q(v) that varies from one frame to another, like the amount by which two clocks are out-of-sync, you would integrate Q(v)*W(v) over the frame velocity interval over which you want the weighted average of Q). And that we can see this because, as you yourself pointed out, as distance separation and relative motion differences decrease all other frame views DO tend to converge on my results. Thus the aggregate WEIGHT OF ALL VIEWS tends to converge on my solution, which is what I meant to say. Sort of like a Bell curve distribution with a point at top representing my solution Would you agree to that? In the case of two clocks at rest and synchronized in a common frame, the only convergence I think we agree on is if you consider a series of cases where the distance between the two clocks approaches 0, or where the velocity of the frame whose opinion you're considering relative to the rest frame of the two clocks approaches 0 (which may be what you meant by as distance separation and relative motion differences decrease all other frame views DO tend to converge on my results). If you are talking about a FIXED value for the distance between two clocks in their rest frame, and doing a weighted average of larger and larger sets of different frame's opinions about the time difference between the two clocks (eventually including frames with a very large velocity relative to the clocks), then what value this average would converge to would depend entirely on the weighting function. As I said a weighting function that looks uniform in one frame (equal velocity intervals have equal weight when you integrate over the integral) will look non-uniform in other frames, so I can't see a way to define a weighting function that doesn't privilege one frame at the outset. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Wed, Mar 5, 2014 at 2:42 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Yes, but respectfully, what I'm saying is that your example doesn't represent my method OR results. In your example of A and B separated but moving at the same velocity and direction, and C and D separated but moving at the same velocity and direction, BUT the two PAIRS moving at different velocities, AND where B and C happen to pass each other at the same point in spacetime here is my result. Assuming the acceleration/gravitation histories of A and B are the same and they are twins; AND the acceleration/gravitation histories of C and D are the same and they are twins, then A(t1)=B(t1)=C(t2)=D(t2) which is clearly transitive between all 4 parties. You earlier agreed that if two observers are at rest relative to each other, then if they synchronize clocks in their rest frame, their clocks will also be synchronized in p-time from then on. In your post at http://www.mail-archive.com/everything-list%40googlegroups.com/msg48404.htmlyou responded to one of my questions in this way: 'Yes is the answer to your question if two clocks are at rest relative to one another and synchronized according to the definition of simultaneity in their mutual rest frame, do you automatically assume this implies they are synchronized in p-time? ' You didn't say anything about their ages having to be equal, or about their needing to have had identical acceleration histories before this. For example, if I and some stranger named Jimbo are at rest relative to each other in an inertial frame in flat SR spacetime (no gravity), and in this frame my 37th birthday is simultaneous with Jimbo's 20th birthday, then if I set my clock to T=0 on my 37th birthday and he sets his clock to T=0 on his 20th birthday, isn't this sufficient to demonstrate that our clocks will be synchronized in p-time from then on (provided we both remain at rest in this frame), regardless of how either of us may have accelerated *before* we came to rest in this frame? (assuming of course that I came to rest before my 37th birthday, and Jimbo came to rest before his 20th) Even if you somehow don't agree with this, I can easily fill in some details about the past history of my example to give A/B and C/D symmetrical accelerations, if you wish--see below. We don't know what t1 and t2 are because you haven't specified their acceleration histories or birth dates, but whatever they are the equation above will hold. OK, I don't think it should be necessary to specify acceleration histories or ages if you agree with my statement about me and Jimbo above, but if you disagree with that statement I can give details about each pair's past history, though it makes the example a bit more complicated. Say that in the frame F where A and B are at rest during the period I described, A and B were originally at rest at position x=12.5, with both having the same ages, and let's say that their proper time clocks have been set to read T = -18 years at the moment they were born (it is the custom in their society to have their proper time clock tell how far from voting age they are, so for example when they turn 15 their clock reads T=-3, when they turn 28 their clock reads T=10, etc.). Then each of them simultaneously began to accelerate in opposite directions with a fixed proper acceleration of 1 light year/year^2, and after each had traveled a distance of 6.25 light years from their starting position in this frame, they began to decelerate (i.e. turn their rockets around and accelerate in the opposite direction, lowering their speed in this frame) at the same proper acceleration of 1 light year/year^2. After they each had traveled another 6.25 light years and come to rest in this frame, they stopped decelerating and simply remained at rest. Each of them will have then traveled a distance of 12.5 light years from their original starting position of x=12.5 light years, with A at position x=25 light years, and B at position x=0 light years. Hopefully you agree that because their accelerations are completely symmetrical in the frame where they were originally at rest with the same ages, in this frame identical ages will still be simultaneous after they finish the acceleration/deceleration phase and come to rest. So, let's just say that they come to rest simultaneously at t=-12 in this frame, and at this moment their clocks both read T=-12, meaning they are both turning 6 at the moment they stop accelerating. After this, their x(t) and T(t) functions are just as I described. As for C and D, let's switch over to the frame F' where THEY are at rest during the period I describe, whose coordinates I had previously labeled as x' and t' (and given the Lorentz transformation equations for converting from x,t to x',t'). Say that in frame F', they were both originally at rest at position x'=7.5, again with both having the same ages, and both having their proper time clocks read a time of T

### Re: Block Universes

On Wed, Mar 5, 2014 at 2:52 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Yes, the views are infinite on several axes, but that can be addressed simply by enumerating views at standard intervals on those axes. But velocity intervals which are equal when the velocities are defined relative to one frame are not equal when the velocities are defined relative to a different frame. I already mentioned an example where if a frame 1 has velocity v=0.1c relative to me and another frame 2 has velocity v=0.15c relative to me, then the interval between them is 0.05c from my perspective, and likewise if a frame 3 has velocity v=0.9c relative to me and another frame 4 has velocity v=0.95c relative to me, then they have the same interval of 0.05c from my perspective; but for another observer moving at v=0.8c relative to me, frame 1 has a velocity of -0.761c and frame 2 has a velocity of -0.739c (so the interval between 1 and 2 is 0.022 for this observer), whereas frame 3 has a velocity of 0.357c and frame 4 has a velocity of 0.625c (so the interval between 3 and 4 is 0.268c for this observer, more than ten times larger than the interval between 1 and 2). These velocities are calculated using the relativistic velocity formula at http://math.ucr.edu/home/baez/physics/Relativity/SR/velocity.html where u = -0.8c is my velocity relative to the second observer, and v is the velocity of any given frame 1,2,3, or 4 relative to me. Point is, if your intervals are equal relative to one frame but unequal relative to all other frames, then you are privileging a particular frame's perspective from the start. Or you could equally integrate over the continuous functions. As I said, the only way to do this is to use some sort of weight/measure function, and a weight/measure function which is uniform when plotted against velocity in one frame will be non-uniform when plotted against velocity in other frames, so there doesn't seem to be a way of picking such a function that doesn't privilege one frame from the start. Considered together simply means you plot the correlation each frame view (at the standard intervals as above) gives and see how they cluster. Which I'm pretty sure will be around my result. The will cluster around the judgment of whatever frame you choose to privilege from the start, either by your definition of equal intervals or by your weighting/measure function. So, using this to conclude anything about the actual correlation would just be another piece of circular reasoning. Jesse You don't need to view the resulting graph from any frame as you seem to suggest, because the graph is OF the actual all frame view results. For every frame you simply calculate the apparent lack of simultaneity between two events Nonsiimultaneity=(t1-t2) and plot it relative to the simultaneity that my method claims is actual. Edgar On Wednesday, March 5, 2014 2:13:24 PM UTC-5, jessem wrote: On Wed, Mar 5, 2014 at 1:27 PM, Edgar L. Owen edga...@att.net wrote: Jesse, Yes, you are right. I phrased it incorrectly. What I meant to say was not that each individual view was somehow weighted, but that all views considered together would tend to cluster around m ... -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Wed, Mar 5, 2014 at 3:12 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, PS: It is well known that accelerations and gravitation are the ONLY causes that produce real actual age rate changes. These real actual age rate changes are real and actual because 1. ALL OBSERVERS AGREE on them when they meet up and check them, and 2.BECAUSE THEY ARE PERMANENT. No, they produce real actual differences in TOTAL ELAPSED PROPER TIME BETWEEN MEETINGS, which all frames agree on. This tells us nothing about the moment-by-moment rates of each clock between meetings, unless you are simply talking about the AVERAGE ticking rate between meetings (and all frames do agree on the ratio between two clock's AVERAGE ticking rate between meetings, since the average ticking rate for clock #1 between meetings in any frame is [proper time elapsed on #1 between meetings / coordinate time between meetings] and the average ticking rate for clock #2 is [proper time elapsed on #2 between meetings / coordinate time between meetings], thus the ratio of the two averages is [proper time elapsed on #1 between meetings / proper time elapsed on #2 between meetings] which all frames will agree on). Relativity agrees on this when the parties MEET. All my method does is to give a method to calculate these real actual changes BEFORE they meet, when the parties are still separated or in relative motion or acceleration or gravitation. It gives a method which is based on simply ASSUMING FROM THE START that the clock rates behave a certain way between the meetings, without ever deriving or demonstrating this from more basic premises. Even a fellow presentist could easily disagree with your assumptions, and you would have no ARGUMENT for convincing him that your assumptions are correct, using starting premises that you both could agree on. And as always, my example with two pairs of twins demonstrates that your methods lead to a direct contradiction where two different ages of A have to labeled simultaneous in p-time--if you disagree, the only intellectually honest way to show I'm wrong is to go through my numbered STATEMENTs about p-time simultaneity, and tell me which is the first that is not a valid inference using your method. This is incredibly simple to understand if you can just escape the notion that all VIEWS of an age relationship are somehow the same as the ACTUAL relationship itself. The views DO differ and these VIEWS ARE VALID VIEWS, but they don't affect the actual RELATIONSHIP THEY ARE VIEWING which is what my method calculates. Again, this is a difference in INTERPRETATIONS of relativity. It does NOT contradict the equations of relativity itself. It simply uses the one that describes the actual relationship rather than ones that describe VIEWS of that relationship. Aren't you at least able to understand what I'm saying even if you don't agree with it? I see no evidence you are even able to do that I understand that your method gives a way of deciding which events are simultaneous in p-time in your theory, it just that: a) I don't think you have any argument for the validity of your method that doesn't simply assume p-time simultaneity works the way you want it to from the start, something that even another presentist who believes in absolute simultaneity could reasonably disagree with b) I think your method can be used to derive a contradiction, even though you don't understand that yet and seem to be refusing to engage with the nitty-gritty details of my example. Jesse On Wednesday, March 5, 2014 2:13:24 PM UTC-5, jessem wrote: On Wed, Mar 5, 2014 at 1:27 PM, Edgar L. Owen edga...@att.net wrote: Jesse, Yes, you are right. I phrased it incorrectly. What I meant to say was not that each individual view was somehow weighted, but that all views considered together would tend to cluster around m ... -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Wed, Mar 5, 2014 at 4:47 PM, LizR lizj...@gmail.com wrote: If you have a continuum of inertial frames with velocities ranging from +c to -c in all possible directions, how are you going to integrate over them? Isn't there a measure problem over an uncountably infinite set? There's no inherent problem with defining measures on uncountably infinite sets--for example, a bell curve is a continuous probability measure defined over the infinite real number line from -infinity to +infinity, which can be integrated over any specific range to define a probability that a result will fall in that range. But as I've said, the problem is that although you can define a measure over all frames in relativity, if it looks like a uniform distribution when you state the velocity of each frame relative to a particular reference frame A, then it will be a non-uniform distribution when you state the velocity of each frame relative to a different reference frame B, so any such measure will be privileging one frame from the start. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Tue, Mar 4, 2014 at 12:19 PM, Jesse Mazer laserma...@gmail.com wrote: So you are just going to COMPLETELY IGNORE my response, which pointed out that your supposed error relied on using the ambiguous phrase B's and C's proper ages are simultaneous in p-time because they are at the same place in spacetime to describe my views, and interpreting it in a way that I would never had agreed with? Again, this phrase could be interpreted two possible ways: 1. If B's proper age at this point in spacetime in T, then C's proper age at this point in spacetime must be T as well (i.e. their proper ages are simultaneous in the sense that they must reach the same age simultaneously). 2. If B and C's worldlines both pass through a specific point in spacetime P, and B's age is T1 when she passes through P, while C's age is T2 when she passes through P, then B must be at age T1 simultaneously with C being at age T2 (i.e. whatever two specific ages they have at P, they must reach those two ages simultaneously, even if the two ages are different) Minor typo in #1 there, it should read If B's proper age at this point in spacetime is T, not in T. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Tue, Mar 4, 2014 at 4:04 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, BTW, in spite of your claim it can't be done, here is another simple way for any two observers at rest with respect to each other but separated by any arbitrary distance in space to determine their 1:1 age correlation. If A and B are separated at any distance but at rest with respect to each other A sends B a light message telling B what A's current age is, and B immediately reflects that light message back to A with B's current age reading attached. Because they are at rest A knows that the actual age difference is A's CURRENT age - B's REPORTED age + 1/2 delta c (half the light signal's round trip time). In this way A determines a unique 1:1 age correlation between his and B's age that will hold for as long as they are at rest. B can use the same method to determine his 1:1 age correlation with A. A and B do NOT have to synchronize the signals to do this. This is a valid method for determining what ages are simultaneous in the inertial frame where they are both at rest. But there is no basis in relativity for judging this frame's views on simultaneity to be any more valid than another frame's. This gives both A and B their single correct 1:1 age correlation at any distance which holds so long as they are at rest with respect to each other. Again, you present no argument for why this is the single correct correlation, you just assert it. Of course other observers may see this differently but IT'S NOT THEIR AGE CORRELATION, IT'S ONLY A'S AND B'S AGE CORRELATION and A and B can determine exactly what that correlation is. Do you agree? No. You already agreed in an earlier post that for an inertial observer to label the frame where they are at rest as their own frame is purely a matter of HUMAN CONVENTION, not an objective reality that is forced on them by nature. So even if we ignore these other observers, there is nothing stopping A and B from using a different convention to define their own frame, such as the inertial frame where they both have a velocity of 0.99c along the x-axis. I know you will claim it's not valid since other observers may view it differently, but frankly A and B's age correlation is NONE OF THEIR BUSINESS! Again, you are conflating observers with frames, even though you earlier acknowledged that any link between particular observers and particular frames is just a matter of convention. I'll respond to the rest of your post later when I have more time... OK, thanks. Please prioritize my latest post discussing the scenario with A/B and C/D and statement #1 vs. statement #2, since it seems that your original argument for an error in my analysis was based on falsely imagining I was asserting statement #1 rather than statement #2. Since the analysis really only depends on #2 which you seem to agree with, I would like to proceed with the analysis of this scenario to see if you can find any other reason to object to any other step in the reasoning--if you can't, then presumably you will have no basis for denying the final conclusion that two different ages of the same observer A would have to be simultaneous in p-time, according to your own rules. Jesse On Tuesday, March 4, 2014 2:19:46 PM UTC-5, jessem wrote: On Tue, Mar 4, 2014 at 2:02 PM, Edgar L. Owen edga...@att.net wrote: Jesse, You ask me to choose between 1. and 2. 1. If B's proper age at this point in spacetime is T, then C's proper age at this point in spacetime must be T as well (i.e. their proper ages are simultaneous in the sense that they must reach the same age simultaneously). 2. If B and C's worldlines both pass through a specific point in spacetime P, and B's age is T1 when she passes through P, while C's age is T2 when she passes through P, then B must be at age T1 simultaneously with C being at age T2 (i.e. whatever two specific ages they have at P, they must reach those two ages simultaneously, even if the two ages are different) First I assume that by passing through the same point in spacetime you mean that the worldlines cross at P simultaneously by the operational definition of no light delay. 1. is true only in a SYMMETRIC case. In the symmetric case they would have the same ages as they pass through the same point P, but in that case they have the same ages during the WHOLE trip so no big surprise. 2. is true in all cases. The actual ages T1 and T2 at which they simultaneously cross will stand in a 1:1 correlation, but ONLY AT THAT POINT P because their ages could be different due to acceleration differences either before or after. Thanks for the clear answer. So now you hopefully see that you must retract your claim that there's an error in my comments about the scenario with the two pairs of twins A/B and C/D, since I never asserted anything remotely resembling #1, my point about ages that occur at the same point in spacetime being

### Re: Block Universes

On Tue, Mar 4, 2014 at 4:57 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Good, we agree it's a valid method for determining 1:1 age correlations in a common inertial frame in which they are both at rest. I claim that frame is the correct one to determine the actual age correlation because it expresses the actual relation in a manner both A and B agree You are avoiding my question of whether identifying this frame with A and B's view or perspective is just a matter of convention as you previously seemed to agree, or whether it is tied to them in some more fundamental way. If it's just a matter of convention, then A and B could equally well agree to define any other frame as their own view of the situation. is transitive among all observers, AND is the exact same method that gives the correct answer WHEN A AND B MEET and everyone, even you, agrees on the 1:1 age correlation. Our disagreement over choice of frames is spinning its wheels and not getting anywhere. It's a matter of how to INTERPRET relativity, rather than relativity itself. And I have given very convincing reasons why a privileged frame that preserves the actual physical facts that affect age changes is appropriate. You just don't agree with them. But you refuse to answer my very simple questions about your reasons, like my question about whether you ASSUME FROM THE START that a particular definition of simultaneity (the one you prefer) is the actual reality, or whether you claim to have convincing reasons for this definition of simultaneity representing reality that don't simply assume it from the start. As to your example claiming to prove my method leads to a contradiction, just give me the bottom line, a simple synopsis. I don't have the time to wade through a detailed example only to find the only disagreement is over choice of frames again. I promise you the example has nothing to do with any frames other than the ones in which each pair is at rest. Again, the only assumptions about p-time that I make in deriving the contradiction are: ASSUMPTION 1. If two observers are at rest in the same inertial frame, then events on their worldlines that are simultaneous in their rest frame are also simultaneous in p-time ASSUMPTION 2. If two observers cross paths at a single point in spacetime P, and observer #1's proper time at P is T1 while observer #2's proper time at P is T2, then the event of observer #1's clock showing T1 is simultaneous in p-time with the event of observer #2's clock showing T2. ASSUMPTION 3. p-time simultaneity is transitive That's it! I make no other assumptions about p-time simultaneity. But if you want to actually see how the contradiction is derived, there's really no shortcut besides looking at the math. If you are willing to do that, can we just start with the last 2 questions I asked about the scenario? Here's what I asked again, with a few cosmetic modifications: Please have another look at the specific numbers I gave for x(t), coordinate position as a function of coordinate time, and T(t), proper time as a function of coordinate time, for each observer (expressed using the inertial frame where A and B are at rest, and C and D are moving at 0.8c), and then tell me if you agree or disagree with the following two statements: For A: x(t) = 25, T(t) = t For B: x(t) = 0, T(t) = t For C: x(t) = 0.8c * t, T(t) = 0.6*t For D: x(t) = [0.8c * t] + 9, T(t) = 0.6*t - 12 --given the x(t) functions for B and C, we can see that they both pass through the point in spacetime with coordinates x=0, t=0. Given their T(t) functions, we can see that B has a proper time T=0 at those coordinates, and C also has a proper time T=0 at those coordinates. Therefore, by ASSUMPTION 1 above, the event of B's proper time clock reading T=0 is simultaneous in p-time with the event of C's proper time clock reading T=0. Agree or disagree? --given the x(t) functions for A and D, we can see that they both pass through the point in spacetime with coordinates x=25, t=20. Given their T(t) functions, we can see that A has a proper time T=20 at those coordinates, and D has a proper time T=0 at those coordinates. Therefore, by ASSUMPTION 1 above, the event of A's proper time clock reading T=20 is simultaneous in p-time with the event of D's proper time clock reading T=0. Agree or disagree? (if you don't understand the math of how to use x(t) to determine whether someone passed through a given point in spacetime with known x and t coordinates, or how to determine their proper time T at this point, then just ask and I will elaborate) If you agree with both of these, then I will proceed to the next few agree/disagree statements that follow from the three assumptions, and if you agree with them all you'll have no way to avoid the contradiction. On the other hand if you ASSUME privileged frames the way I do and think my method of using them leads to a contradiction that isn't just another disagreement over

### Re: Block Universes

On Tue, Mar 4, 2014 at 5:45 PM, Jesse Mazer laserma...@gmail.com wrote: I promise you the example has nothing to do with any frames other than the ones in which each pair is at rest. Again, the only assumptions about p-time that I make in deriving the contradiction are: ASSUMPTION 1. If two observers are at rest in the same inertial frame, then events on their worldlines that are simultaneous in their rest frame are also simultaneous in p-time ASSUMPTION 2. If two observers cross paths at a single point in spacetime P, and observer #1's proper time at P is T1 while observer #2's proper time at P is T2, then the event of observer #1's clock showing T1 is simultaneous in p-time with the event of observer #2's clock showing T2. ASSUMPTION 3. p-time simultaneity is transitive That's it! I make no other assumptions about p-time simultaneity. But if you want to actually see how the contradiction is derived, there's really no shortcut besides looking at the math. If you are willing to do that, can we just start with the last 2 questions I asked about the scenario? Here's what I asked again, with a few cosmetic modifications: Please have another look at the specific numbers I gave for x(t), coordinate position as a function of coordinate time, and T(t), proper time as a function of coordinate time, for each observer (expressed using the inertial frame where A and B are at rest, and C and D are moving at 0.8c), and then tell me if you agree or disagree with the following two statements: For A: x(t) = 25, T(t) = t For B: x(t) = 0, T(t) = t For C: x(t) = 0.8c * t, T(t) = 0.6*t For D: x(t) = [0.8c * t] + 9, T(t) = 0.6*t - 12 --given the x(t) functions for B and C, we can see that they both pass through the point in spacetime with coordinates x=0, t=0. Given their T(t) functions, we can see that B has a proper time T=0 at those coordinates, and C also has a proper time T=0 at those coordinates. Therefore, by ASSUMPTION 1 above, the event of B's proper time clock reading T=0 is simultaneous in p-time with the event of C's proper time clock reading T=0. Agree or disagree? --given the x(t) functions for A and D, we can see that they both pass through the point in spacetime with coordinates x=25, t=20. Given their T(t) functions, we can see that A has a proper time T=20 at those coordinates, and D has a proper time T=0 at those coordinates. Therefore, by ASSUMPTION 1 above, the event of A's proper time clock reading T=20 is simultaneous in p-time with the event of D's proper time clock reading T=0. Agree or disagree? Another little correction--in the last two paragraphs there, where I said Therefore, by ASSUMPTION 1 above, I should have written ASSUMPTION 2, since in both cases I was deriving p-time simultaneity from the fact that two clock readings happened at the same point in spacetime. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Mon, Mar 3, 2014 at 10:03 AM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Your position becomes more and more absurd. My position is simply that for any question on which different frames give different answers, there is no physical basis for judging one frame's judgments to be reality while others are not. I guarantee you that any physicist would agree with this. You claim they DO have a unique 1:1 correlation of their ages when they are together but they DON'T when they separate. So how far do they have to separate before this correlation is lost? 1 meter? 1 kilometer, 1 light year? Any finite number--one trillionth of a nanometer, say. The theory says that no matter how small the distance D you choose, if you have an inertial frame where two clocks are at rest and synchronized a distance D apart, then in another inertial frame where the two clocks are moving along the axis between them at speed v, at any given moment in this new frame one clock's time will be ahead of the other's by vD/c^2. There is a maximum to how far their times can be out-of-sync since v must be smaller than c, this implies that no inertial frame will see them as being out-of-sync by a time greater than or equal to D/c (so if the two clocks are 1 light-second apart in their rest frame, or 299792458 meters apart, any other frame will see them out-of-sync by less than a second). And this means that if you are rounding ages off at some point, in practice you may not have to worry about disagreements in simultaneity between frames--if two people are precisely the same age in their rest frame and are standing only a meter apart in their inertial rest frame, all other frames will say their ages differ by less than 1/299792458 of a second, so obviously if you're rounding their ages to the nearest second you'll still say they're the same age no matter what inertial frame you're using. But if you want to talk about physical reality rather than mere practical approximations, the fact remains that different frames will disagree somewhat on which ages are simultaneous for ANY finite separation, and in relativity there can NEVER be a physical basis for saying that one frame's judgments are a true representation of physical reality while other's are not. And is the correlation lost all at once as they separate or gradually? And if all at once, what is the threshold distance where correlation is lost? And if gradually what is the relativistic formula that determines how much the correlation falls off with distance? See above, if the clocks are at rest a distance D apart and synchronized in their own rest frame, then in another frame moving at speed v along the axis between the two clocks, at any given moment in this new frame the clocks are out-of-sync by vD/c^2. This can be derived directly from the Lorentz transformation which tells you the coordinates of any event in frame #2 if you already have its coordinates in frame #1. The fact is that both twins DO HAVE AN ACTUAL AGE AT ALL TIMES. You've already agreed to this obvious fact. Thus there absolutely MUST be an actual correlation of those ages. That is pure logic, not relativity. That isn't logical at all, in fact it's a complete non sequitur (note that you make no attempt to actually explain the 'logic' that leads you from the premise to the conclusion here). Once again I would mention the geometric analogy: --If you have two spatial paths between points A and B on a 2D plane, then at any given point P on a specific path, there is an actual distance along the path between point A and point P, which could be measured by a flexible measuring tape laid along the path. This distance along the path from A to P--call it the proper path distance from A to P--is totally coordinate-independent, in the sense that if different Cartesian coordinate systems have different coordinate descriptions of the same path, they can each use their own coordinates to calculate this proper path distance from A to P and they will all get the same answer. But if you use different Cartesian coordinate systems to assign x,y coordinates to points on the plane, two points P1 and P2 on *different* paths may have the same y-coordinate in one coordinate system, but different y-coordinates in another coordinate system. So the question do two points on different paths share a common y-coordinate?, unlike the question what is the proper path distance between two points on a single path?, is one that different Cartesian coordinate systems answer differently. But I don't think anyone would ever claim that one Cartesian coordinate system's answer to the latter question would be physically correct while other coordinate systems are objectively physically wrong--the notion of separated points in space having the same y-coordinate is an INTRINSICALLY coordinate-based idea, it HAS no physical reality independent of an arbitrary choice of coordinate system. All of this is exactly analogous

### Re: Block Universes

On Mon, Mar 3, 2014 at 12:36 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, OK, this is some progress. Now you've gone from saying there is NO correlation at all, to the ages ARE CORRELATED WITHIN SOME LIMIT. In other words we DO know that for any set of twins we can always say that their ages ARE the same within some limits. Correct? This is a VERY BIG CHANGE in your stated position, from NO correlation at all to SOME correlation... Once again your argument turns on vague use of language. You were consistently talking about a 1:1 correlation, so naturally I was using correlation in this sense too. If we say all inertial frames agree that my age T' is simultaneous with my twin's age having some value between T1 and T2, but they disagree on the precise value that is NOT a 1:1 correlation, period. So there's been no change in my position, it's you whose changing the meaning of correlation in mid-argument in an attempt to prove me wrong. You though continue to claim that all frames are equally valid, even if they DO NOT preserve the actual age changing acceleration effects between the twins, What do you mean by actual age changing acceleration effect? If you're talking about things that are directly measurable without use of a particular frame--like each twin's proper age at any specific event on his worldline (including their identical proper ages at the point in spacetime where they reunite), or each twin's proper acceleration as a function of proper age, then all frames DO preserve these effects. If instead you mean the idea that identical ages of separated symmetrically-accelerating twins are simultaneous in absolute, non-frame-dependent terms, then YOUR ARGUMENT IS TOTALLY CIRCULAR--you are simply assuming from the start that symmetrical acceleration implies that identical ages are simultaneous in actual, absolute terms, WITHOUT DERIVING THIS IDEA FROM ANY MORE BASIC PREMISES. while I claim that IF we properly choose a frame that DOES preserve the actual age changing acceleration effects that we narrow that limit to zero resulting in an EXACT 1:1 age correlation. Yep, that sounds pretty circular all right. As near as I can tell, the structure of your argument is this: 1. Assume without any prior argument that for symmetrically-accelerating twins, the actual truth about simultaneity is that identical ages are simultaneous. 2. Observe that there is only one frame that preserves this actual truth. 3. Therefore, only this frame is valid, other frames are not. 4. If we use this valid frame we can find a unique 1:1 correlation in their ages--and that is supposed to demonstrate the validity of premise #1 above! Hopefully you can see that this argument would be completely circular. If you think this isn't a fair representation of your own argument, then perhaps you can lay your argument out in a step-by-step manner as above, with each successive step being obviously derivable from only the previous steps. You, in fact, have previously agreed that IF we choose the frame in which the symmetric accelerations were preserved All frames agree the proper accelerations as a function of each twin's proper time are symmetric. By the frame in which symmetric accelerations were preserved do you mean that each twin's acceleration as a function of COORDINATE time in that frame is symmetric? that we DO get an exact 1:1 correlation, you just disagree that that frame is privileged because it preserves the actual age changing symmetric accelerations like I claim. Do you have any argument to DERIVE the conclusion that one frame's acceleration and aging as a function of COORDINATE time is actual, or is this just something you assume from the start and have no way to derive from any more basic premises? So I suggest that for the moment we ASSUME we should choose that frame, and then see if it can be consistently applied in a transitive manner to achieve a common age correlation between ALL observers. If it can't my theory is falsified. If it can then we can still agree to disagree about how frames should be applied to analyze specific physical relationships. Would you consider it a falsification of your theory to show that your assumption about simultaneity for symmetrically-moving observers (combined with transitivity and the idea that events at the same space and time coordinates in some inertial frame are automatically simultaneous in p-time) can lead in certain scenarios to a situation where we are forced to conclude that two different proper times of the SAME observer (Bob's proper time clock reading 0 and Bob's proper time clock reading 20, say) are simultaneous in p-time? If so, this sort of falsification is exactly what I have derived in my Alice/Bob/Arlene/Bart scenario from Feb. 9 at https://groups.google.com/d/msg/everything-list/jFX-wTm_E_Q/pxg0VAAHJRQJwhich you have CONSISTENTLY FAILED TO ADDRESS on all the myriad occasions I have reminded you of

### Re: Block Universes

On Mon, Mar 3, 2014 at 3:45 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, No, it was you that said there was NO correlation. Jeez Edgar, you really need to work on your reading comprehension. I just got through AGREEING that I had said that there wasn't a correlation, but I explained that this was because I was using correlation in the way YOU had consistently been using it up until now, to refer to a 1:1 correlation in which each proper age of a twin is matched up to one unique proper age of the other twin. The archive at http://www.mail-archive.com/everything-list@googlegroups.com/ has a better search function than google's archive (returning individual posts rather than threads), so I searched for posts from Edgar L. Owen with correlate or correlation in them, results here: http://www.mail-archive.com/search?a=1l=everything-list%40googlegroups.comhaswords=correlatefrom=Edgar+L.+Owennotwords=subject=datewithin=1ddate=order=datenewestsearch=Search http://www.mail-archive.com/search?a=1l=everything-list%40googlegroups.comhaswords=correlationfrom=Edgar+L.+Owennotwords=subject=datewithin=1ddate=order=datenewestsearch=Search Earliest posts on the block time thread I could find in these searches (that were directed at me, and not some other poster) were these from Feb. 12 and 13 (shown in order below), where you can see from the quotes that you were talking specifically about 1:1 correlations that map clock times of one to specific clock times of the other: http://www.mail-archive.com/everything-list%40googlegroups.com/msg48613.html So all observers are always in the same p-time moment. Now it's just a matter of correlating their clock times to see which clock times occurred in any particular current moment of p-time. http://www.mail-archive.com/everything-list%40googlegroups.com/msg48716.html Do you see how this mutual agreed on understanding of how each's clock time varies in the other's frame always allows each to correlate their own comoving clock time with the comoving (own) clock time of the other? In other words for A to always know what B's clock time was reading when A's clock time was reading t, and for B to always know what A's clock time was reading when B's clock time was reading t'? http://www.mail-archive.com/everything-list%40googlegroups.com/msg48750.html Do you understand that if we have equations for t' in terms of t in A's frame, and t in terms of t' in B's frame, that we can always establish a 1: 1 correlation between t in A's frame and t' in B's frame? And in subsequent posts I'm pretty sure you always used correlation in the same manner, repeating the phrase 1:1 correlation many times (you may have gotten this phrase from ghibbsa, who used it in a Feb. 6 post at http://www.mail-archive.com/everything-list%40googlegroups.com/msg48264.htmlthat you quoted in one of your posts that came up in the search results). A similar search for posts by me that use correlate or correlation doesn't show any posts of mine using these words on the thread prior to your three posts to me above, and subsequently I always used correlation in the same sense that YOU had been consistently using it, to refer to a precise 1:1 correlation in ages/proper times. In any case that's irrelevant if we know you now accept that there is a very LARGE correlation in most situations, and a definable correlation in ALL situations. That there is always SOME correlation. By actual age changing effect I mean proper accelerations and gravitations measurable by a comoving scale at specific clock tick events on his proper clock. There is no doubt these are real actual CAUSES with specific measurable values that thus must have real actual EFFECTS with specific actual values. So you are now saying that all frames DO preserve these effects? What EFFECTS do you think they cause? Can you name a SPECIFIC effect on a SPECIFIC variable used in relativity? As I've told you before, if you are talking about some notion of a change in clock rate, then in relativity there is no frame-independent way to assign a specific actual value to the concept of a clock rate, the clock rate can only be defined relative to a particular coordinate system, so the clock rate at a particular event on the clock's worldline can have DIFFERENT values depending on what coordinate system you use. So, if this is in fact what you mean by effects, then I would DENY that proper accelerations have real actual EFFECTS with specific actual values. If you mean something else by real actual EFFECTS, you'll have to name the specific effect or your argument will be hopelessly vague. Your 4 point representation of my method MAY BE circular, but my actual method is NOT circular. Your statement 1. is an incorrect statement of my theory. What I assume FIRST in the symmetric case is NOT simultaneity of ages but simultaneity of the AGE CHANGING EFFECTS that relativity itself identifies, namely acceleration and gravitation. Not

### Re: Block Universes

On Sat, Mar 1, 2014 at 7:09 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, To address your points in order: 1. Yes, you said that proper ages are invariant. But note the important point that the proper age of A to himself is a direct observation (he looks at his age clock), but to anyone else is a computation and NOT an observation. If he looks at his age clock, that's a direct measurement that is not specifically tied to ANY frame, including his own comoving frame. And there's nothing stopping an observer who is moving relative to him from stealing a glance at his age clock too as she passes him nearby (or looks at him through her telescope), so she can make a direct measurement of his age just as easily. A reference frame only needs to be used when you want to PREDICT some fact you don't already know through direct measurement, given some other known facts. For example, if you know that someone has a coordinate velocity v at coordinate time t0 in some frame, and you know their proper age is T0 at coordinate time t0, then as long as they move inertially, you can PREDICT that at some later coordinate time t1, their proper age T1 will be equal to T0 + (t1 - t0)*sqrt[1 - (v/c)^2]. Of course if you happen to be using the person's inertial rest frame where v=0, this formula reduces to the simple one T1 = T0 + (t1 - t0), but this still qualifies as a CALCULATION to predict his proper age at a later coordinate time t1, not a direct measurement. In fact from their native comoving frames they will observe A at some other age than their calculation. So the calculations trump the views. Huh? You're not making any sense--you just got through agreeing proper ages are invariant, how can you still maintain they'll observe A at some other age than their calculation if you agree all frames will predict exactly the same age for him at any event on his worldline, and this will also be the age that he will be observed to have on his personal clock at that event? Do you just mean that the time coordinate they assign to that event may be different than his proper age? That would be true, but no one familiar with relativity would conflate a time coordinate with an age, and anyway it's quite possible to have an inertial coordinate system where he's at rest but his age still doesn't match the coordinate time, because his birth is assigned some time coordinate different from t=0. Thus it is valid in relativity to CALCULATE things we CANNOT OBSERVE from our frame. Actual physical measurements can be seen by any observer, like the example of looking at the age clock of someone you're in motion relative to, so there's nothing that one person can observe that someone else cannot observe just because they're in a different rest frame, if by observe you mean measure using a physical instrument. Of course, actual physical measurements may be interpreted differently depending on what frame we use--for example, if I see an object pass the x=10 meters mark on some ruler when the clock there reads t=5 seconds, and later pass the x=20 meters mark on the same ruler when the clock there reads t=6 seconds, then if I am using a frame that defines the ruler and clocks to be at rest and the clocks to be synchronized, I'll say these measurements imply the object had a velocity of 10 meters per second, but if I'm using a frame where the ruler itself is moving and the clocks are out of sync, I can say that the velocity of the object itself was larger or smaller. That's what I do to establish 1:1 correlations of actual ages. I use calculations that trump Views, that trump observations. We don't always have to use frame views to establish relativistic truth. Do you agree with that? You must if you accept proper age invariance. Of course, you can determine relativistic truth by direct measurement, like looking at someone's clock. But this only applies to quantities that are frame-invariant, like proper time or proper acceleration. Other quantities are DEFINED with respect to reference frames, there's absolutely no way to determine them in a way that doesn't involve a frame. The x-coordinate of an event would be an example of a quantity that's defined in terms of a reference frame, you can't determine some object's x-coordinate except in reference to a particular coordinate system that has a particular spatial origin and its x-axis oriented in a particular direction. Likewise, the t-coordinate of an event can only be defined relative to a particular frame, and since simultaneity is DEFINED in relativity to mean nothing more than events that have the same t-coordinate, simultaneity can only be defined relative to a particular frame (talking specifically about physical definitions of simultaneity in relativity--this doesn't preclude the possibility of some metaphysical truth about simultaneity that's impossible to demonstrate experimentally, and of course it's conceivable that relativity will turn out to be

### Re: Block Universes

On Sun, Mar 2, 2014 at 12:13 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, To answer your final question. If I understand your 3 points correctly then I agree with all 3. Though I suspect we understand them differently. When you spring your 'proof' we will find that out. Thanks for addressing the question. As I mentioned in my previous comment to you, the proof has already been sprung--it is the Alice/Bob/Arlene/Bart example from Feb. 9 at https://groups.google.com/d/msg/everything-list/jFX-wTm_E_Q/pxg0VAAHJRQJwhich I have asked you to address in at least ten different posts since then. And to your first points. I agree completely that there is no objective or actual truth about VIEWS of simultaneity from different frames. That is standard relativity which I accept completely. But you still find it impossible to understand we can DEDUCE or calculate an ACTUAL physical simultaneity irrespective of VIEWS of it. And just as proper time invariance is NOT ANY VIEW but a deduction or calculation, we CAN use deductions and calculations that DO NOT correspond to any particular view to determine relativistic truth That such a methodology is permissible? Do you agree that the symmetric relationship defined by the twins executing the exact same proper accelerations at their exact same proper times is a meaningful physical concept? That we can speak meaningfully about a symmetric relationship? Only in terms of coordinate-invariant characterizations of their paths, like the proper acceleration as a function of proper time, or the total proper time elapsed between departing and reuniting. There is no logical reason that this symmetry in coordinate-invariant aspects of their trips somehow forces us to say that a coordinate system where coordinate-dependent aspects of their trips are symmetrical too represents actual physical reality where other coordinate systems do not. Suppose we lay out two measuring tapes on different paths between two intersection points A and B, and these paths are geometrically symmetrical in the sense that each one looks like a mirror image of the other if your mirror is laid out straight between points A and B. Both tapes have their 0 markings coincide with the first intersection point A, and obviously since the two paths are symmetrical, both measuring tapes will have the same marking coincide with the second intersection point B. Obviously we could draw different spatial coordinate axes on the plane, and in some coordinate systems their paths would be symmetrical in coordinate terms--for example, a pair of identical markings on each tape would have the same y-coordinates, and their slopes at these markings would have the same absolute value--while in others they would not. I can sketch out a diagram if you can't visualize what I'm talking about, but assuming you can, do you think that coordinate-based statements based on a symmetrical coordinate system, like the 4-centimeter marks on each measuring tape have the same y-coordinate would represent actual reality, whereas coordinate-based statements in other coordinate systems would not? You've been referring to it as if you do. Note that the twins certainly consider it a meaningful physical scenario because they can exchange and execute specific flight plans on that basis. If so you agree that some frames preserve that real physical relationship and some don't? No, I don't agree. ALL frames preserve the only symmetries I would recognize as objective ones--same proper acceleration as a function of proper time, same proper time when the twins reunite--while other coordinate-depedent statements are not ones I would call a real physical relationship. Note that they are perfectly free to agree to use a coordinate system where the coordinate descriptions of their paths are not symmetrical, and exchange and execute specific flight plans on that basis. If so please tell me why if we want to analyze that ACTUAL real physical relationship we should not choose a frame that preserves it? And second, do you agree my method is consistently calculating something, and that something is transitive, even if you don't agree it's a physically meaningful concept? If you consider more than one pair of twins whose paths cross one another, as I do in my Alice/Bob/Arlene/Bart scenario, then either your method leads to a contradiction where two different ages of the same observer are judged simultaneous, or else you'd have to drop one of the assumptions in your method (meaning it'd no longer be quite the same method). One of those assumptions was transitivity, so in principle you could drop that if you wanted to avoid the contradiction I describe, but as I said in my previous comment, it seems like a much more reasonable assumption to drop is the one that says inertial clocks at rest relative to one another that are synchronized in their rest frame must also be synchronized in p-time. Though as I

### Re: Block Universes

On Sun, Mar 2, 2014 at 2:25 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, I'll address your points in a later post, but first let me run this simple new case by you. Imagine the symmetric trips of the twins continually criss cross each other at 1 second intervals (of their own proper clocks) for the duration of the entire trip. At each 1 second meeting I'm sure you would agree their proper times are in a 1:1 correlation so their proper times are in a 1:1 correlation every second of the duration of the trip and both twins agree on that. There is a 1:1 correlation of proper age clocks at the criss crosses because they are in the same point of space and time by your operational reflected light definition AND they both compute both their 1 second proper time intervals since the last criss cross as the same invariant number as each other, AND they BOTH HAVE AGREED TO CRISS CROSS WHEN EACH OF THEIR PROPER TIMES READS 1 SECOND INTERVALS which in itself ensures the 1:1 correlation of proper times. Sure, there is complete agreement about their respective ages at each crossing-point. Now just take the limit of that and imagine a vanishingly small interval for the criss crosses. If we do that then clearly we can say the twins have a 1:1 correlation of their proper ages at EVERY MOMENT during the entire trip to any limit of accuracy we wish. The problem is that in this limit, they also approach a state of simply moving right alongside each other (since the spatial separation they can achieve between crossings approaches zero), remaining at exactly the same point in space at any given time, so their worldlines are identical. Of course it is true in such a case that their ages will remain the same at every moment in a frame-invariant sense, but this tell us anything about simultaneity in a case where they have a finite spatial separation throughout the trip. Since a criss cross symmetric trip is no different in principle than our previous symmetric trip (only a single meeting) it is clear that we have proven there is a 1:1 proper age correlation for any symmetric trip during EVERY MOMENT of the trip. Edgar On Sunday, March 2, 2014 1:18:27 PM UTC-5, jessem wrote: On Sat, Mar 1, 2014 at 7:09 PM, Edgar L. Owen edga...@att.net wrote: Jesse, To address your points in order: 1. Yes, you said that proper ages are invariant. But note the important point that the proper age of A to himself is a direct observation (he looks at his age clock), but to anyone else is a computation and NOT an observation. If he looks at his age clock, that's a direct measurement that is not specifically tied to ANY frame, including his own comoving frame. And there's nothing stopping an observer who is moving relative to him from stealing a glance at his age clock too as she passes him nearby (or looks at him through her telescope), so she can make a direct measurement of his age just as easily. A reference frame only needs to be used when you want to PREDICT some fact you don't already know through direct measurement, given some other known facts. For example, if you know that someone has a coordinate velocity v at coordinate time t0 in some frame, and you know their proper age is T0 at coordinate time t0, then as long as they move inertially, you can PREDICT that at some later coordinate time t1, their proper age T1 will be equal to T0 + (t1 - t0)*sqrt[1 - (v/c)^2]. Of course if you happen to be using the person's inertial rest frame where v=0, this formula reduces to the simple one T1 = T0 + (t1 - t0), but this still qualifies as a CALCULATION to predict his proper age at a later coordinate time t1, not a direct measurement. In fact from their native comoving frames they will observe A at some other age than their calculation. So the calculations trump the views. Huh? You're not making any sense--you just got through agreeing proper ages are invariant, how can you still maintain they'll observe A at some other age than their calculation if you agree all frames will predict exactly the same age for him at any event on his worldline, and this will also be the age that he will be observed to have on his personal clock at that event? Do you just mean that the time coordinate they assign to that event may be different than his proper age? That would be true, but no one familiar with relativity would conflate a time coordinate with an age, and anyway it's quite possible to have an inertial coordinate system where he's at rest but his age still doesn't match the coordinate time, because his birth is assigned some time coordinate different from t=0. Thus it is valid in relativity to CALCULATE things we CANNOT OBSERVE from our frame. Actual physical measurements can be seen by any observer, like the example of looking at the age clock of someone you're in motion relative to, so there's nothing that one person can observe that someone

### Re: Block Universes

On Sun, Mar 2, 2014 at 6:49 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Just checking but I'm sure you would agree that twins AT REST with respect to each other are the same actual age (have a 1:1 proper age correlation) even if they are SEPARATED by distance? You just don't agree that if they are separated by distance AND in symmetric acceleration that there is any correlation of actual ages possible. Is that correct? No, of course I wouldn't agree that there is any unique actual truth about their ages in this case, nor would any mainstream physicist. What part of all frames are equally valid don't you understand? Or do you not get that if we use an inertial frame where the twins are both moving with the same constant velocity, they do NOT have identical ages at any given moment in this frame? (assuming they had identical ages at any given moment in their rest frame) Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Sun, Mar 2, 2014 at 6:40 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Glad we agree on the first point but, even if there is some minimum time limit to the criss crosses, you miss the real point of my example. Let me restate it: Since a criss cross symmetric trip is NO DIFFERENT IN PRINCIPLE than our previous symmetric trip (only a single meeting) it is clear that we have proven there is a 1:1 proper age correlation for any symmetric trip during EVERY minimum time interval of the trip EVEN IF THERE ARE NO CRISS CROSSES. Nonsense. We both agree that in case A where they are right next to each other throughout the whole trip (same spatial position at every single moment), there is an objective 1:1 correlation in their ages throughout the trip. We disagree about whether there is a 1:1 correlation throughout the trip in case B, where they do NOT occupy the same position through the trip. So now you think you can prove your belief about CASE B by considering a series of cases that IN THE LIMIT would have a 1:1 correlation throughout the trip, even though IN THE LIMIT this just reduces to CASE A, which we already agreed on? Sorry, but this fails basic logic. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Sun, Mar 2, 2014 at 7:01 PM, Jesse Mazer laserma...@gmail.com wrote: No, of course I wouldn't agree that there is any unique actual truth about their ages in this case, nor would any mainstream physicist. Sorry, I wrote too quickly here--what I meant is that I don't agree there is any unique actual truth about the CORRELATION between their ages, i.e. whether or not they reach the same age simultaneously (of course there is still a unique truth about each one's age at any specific event on his worldline). They do reach the same age simultaneously in their comoving inertial frame, but this frame's judgments can't be considered any more valid than a different inertial frame. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Sun, Mar 2, 2014 at 7:44 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, OK good, that's what I assumed you meant. BUT now take the two twins at rest standing on opposite sides of the earth, and then they each start walking in different directions. By your criterion you then have to say that suddenly and instantly there is NO more 1:1 correlation of their ages, that they COMPLETELY AND ABSOLUTELY lose their 1:1 age correlation they had at rest even if they take a SINGLE STEP! You seem to have misunderstood me, although I thought I was pretty clear--I said that they did NOT have a unique actual correlation in their ages when they were at rest relative to each other but at different positions in space, so nothing changes if they start walking, they still don't have any unique actual correlation in their ages. Try reading what I wrote again (with the correction I mentioned that 'any unique actual truth about their ages' has been changed to 'any unique actual truth about the correlation between their ages'): 'No, of course I wouldn't agree that there is any unique actual truth about the correlation between their ages in this case, nor would any mainstream physicist. What part of all frames are equally valid don't you understand? Or do you not get that if we use an inertial frame where the twins are both moving with the same constant velocity, they do NOT have identical ages at any given moment in this frame? (assuming they had identical ages at any given moment in their rest frame)' Jesse On Sunday, March 2, 2014 7:13:31 PM UTC-5, jessem wrote: On Sun, Mar 2, 2014 at 7:01 PM, Jesse Mazer laser...@gmail.com wrote: No, of course I wouldn't agree that there is any unique actual truth about their ages in this case, nor would any mainstream physicist. Sorry, I wrote too quickly here--what I meant is that I don't agree there is any unique actual truth about the CORRELATION between their ages, i.e. whether or not they reach the same age simultaneously (of course there is still a unique truth about each one's age at any specific event on his worldline). They do reach the same age simultaneously in their comoving inertial frame, but this frame's judgments can't be considered any more valid than a different inertial frame. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Sat, Mar 1, 2014 at 9:55 AM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Of course there is a rational justification for selecting one frame over another in many cases. All frames are NOT equal when it comes to representing ACTUAL physical facts. E.g. we can choose various frames to make someone's age pretty much any number we like but nevertheless they are still actually the age they think they are. If Alice is really 30 we can choose a frame in which she is all sorts of different ages I've already told you that proper time at an event on Alice's worldline is frame-independent, did you forget already? If one frame says Alice is 30 at a particular event in her worldline, like the event of her passing a particular object or observer (or her age when she reunites with her twin), then ALL frames say this, there is no need to use her comoving frame to get the correct answer. Different frames may disagree about simultaneity--what Alice's age is at the same moment that Bob turns 40, at a distant spatial location--but this is precisely why physicists don't believe there is any actual physical fact about simultaneity in relativity (this doesn't rule out presentism since there could still be a metaphysical fact about simultaneity, but no physical experiment would be able to determine it if there was, unless relativity turns out to be incorrect in its physical predictions). but she is still actually 30. Different VIEWS of her age don't change her actual age. Isn't that obvious, and don't you agree with this? Don't change her actual age WHEN? Doesn't change her age at some specific event on her worldline, or doesn't change what her age is now at the same moment that some distant observer like Bob reaches a particular age, say 40? If the first I agree that she has an actual age at any given event on her wrodline, but there ARE no different views of this since all frames agree on her proper age at any specific event on her worldline. If the latter I don't agree there is any physical basis for saying she has a unique actual age when Bob is 40, since relativity doesn't give any physical basis for a preferred definition of simultaneity. Your expertise in relativity is clear but you don't seem to understand that all frames are NOT equal when it comes to representing actual physical fact. You don't understand the fundamental notion in relativity that some frames represent actual physical fact, but others represent only HOW OTHER OBSERVERS VIEW those physical facts. Not a physicist in the world would agree with you that there is a fundamental notion in relativity that some frames represent actual physical facts, you appear to be completely confused about the difference between your own p-time views and mainstream relativity. In special relativity there can NEVER be a basis for considering one inertial frame more correct than any other. There are only two kinds of facts in relativity: 1. Facts about frame-independent matters like the proper time of an observer at a particular event on their worldline; all frames agree in their predictions about these, so they don't give any reason to prefer one frame over another. 2. Facts about frame-dependent matters like the coordinate velocity of an object at a particular event on its worldline, or the question of which point on worldline B is simultaneous with a particular point on worldline A; different frames disagree on these matters, and in relativity NO FRAME'S STATEMENTS ABOUT FRAME-DEPENDENT MATTERS ARE CONSIDERED MORE VALID THAN ANY OTHER FRAME'S. If you don't believe me that it's a basic principle of relativity that all frames are considered equally valid and none are preferred over others, here are some quotes from books written by physicists that I found on google books: If one reference frame moves uniformly relative to another, then the two are equally good frames for observing nature, and two identical experiments performed in the two frames will give identical results. --From Relativity for the Questioning Mind by Daniel Styer, at http://books.google.com/books?id=Ebr7YhJcUd0Clpg=PP1pg=PA13 The descriptions of the two sets of observers are equally real and equally valid, each within their own frame of reference. Since no preferred frame exists, there is no objective basis for ascribing any more reality to one description than the other. --From Understanding Relativity: A Simplified Approach to Einstein's Theories by Leo Sartori, at http://books.google.com/books?id=gV6kgxrZjL8Clpg=PP1pg=PA173 If Albert and Betty clap nearly simultaneously, one observer may report that Albert clapped first, whereas a second observer, in motion with respect to the first, may report that Betty clapped first. It makes no sense to ask, 'Who really clapped first?' The question assumes that one viewpoint, one reference frame, is valid or 'real' and the other is not. But time is not absolute; it is a property of a particular frame of reference. Both

### Re: Block Universes

On Sat, Mar 1, 2014 at 5:35 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Let me ask you one simple question. In the symmetric case where the twins part and then meet up again with the exact same real actual ages isn't it completely logical to conclude they must also have been the exact same real actual ages all during the trip? If, as you claim, the same exact proper accelerations do NOT result in the exact same actual ages all during the trip then how in hell can the twins actually have the exact same actual ages when they meet up? It's not that I'm claiming that there's an objective truth that they DON'T have the same ages during the trip. I'm just saying that as far as physics is concerned, there simply IS NO OBJECTIVE OR ACTUAL TRUTH ABOUT SIMULTANEITY, and thus there is neither an actual truth that they are the same age or an actual truth that they are different ages. These things are purely a matter of human coordinate conventions, like the question of which pairs of points on different measuring-tapes have the same y coordinates in any given Cartesian coordinate system. Similarly, questions of simultaneity reduce to questions about which pairs of points on different worldlines have the same t coordinate in any given inertial coordinate system, nothing more. What is the mysterious mechanism you propose that causes twins that do not have the same actual ages during the trip to just happen to end up with the exact same actual ages when they meet? Again, I do not say there is any objective truth that they do not have the same actual ages, I simply say there is no objective truth about which ages are actually simultaneous in some sense that is more than just an arbitrary coordinate convention. But if you're just asking about how things work in FRAMES where they don't have the same actual ages during the trip, the answer is that in such a frame you always find that the answer to which twin's clock is ticking faster changes at some point during the trip, so the twin whose clock was formerly ticking faster is now ticking slower after a certain time coordinate t, and it always balances out exactly so that their clocks have elapsed the same total time when they reunite. If you like I could give you a simple numerical example where I analyze a symmetric trip both from the frame where their velocities are symmetrical, and a different frame where their velocities are non-symmetrical, and show that it does work out that the second frame predicts their ages will be the same when they reunite despite them aging at different rates during different phases of the trip in this frame. Meanwhile, are you going to address the question about whether you agree with the 3 premises that I claim together lead to a contradiction? I'll repost the question from my last post: 'Again, the 3 premises are: 1. If a pair of inertial observers are at rest relative to one another, then events (like clock readings) that are simultaneous in their comoving frame are also simultaneous in p-time 2. Any two events that happen at precisely the same position and time coordinate in a particular inertial frame must be simultaneous in p-time 3. p-time simultaneity is transitive So to start with, please just tell me if you do agree with all these premises, or if there is one or more you disagree with or aren't sure about and require clarification on. And if you disagree with or are not sure about #2, this is the same point in spacetime issue we had been discussing earlier before you stopped responding, so in this case please go back to my last post on the subject at https://groups.google.com/d/msg/everything-list/jFX-wTm_E_Q/dM2tcGYspfMJand respond to that.' Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Fri, Feb 28, 2014 at 11:18 AM, Edgar L. Owen edgaro...@att.net wrote: You point out that from the POV of all arbitrary frames they won't be, BUT the point is we MUST use a frame that MAINTAINS the real and actual symmetry to determine the ACTUAL REALITY of this situation. Why? You give no rational justification for why reality should coincide with the frame where the coordinates assigned to their paths are symmetrical as opposed to any other frame which makes the same physical predictions, this just seems like a quasi-aesthetic intuition on your part. But I also have a more definitive argument against identifying simultaneity in the frame where their paths look symmetrical with any sort of absolute simultaneity--because, as I have said over and over, it leads directly to contradictions when we consider multiple symmetrical pairs of observers, and the transitive nature of absolute simultaneity/p-time. If you will just respond to my Feb 24 post at https://groups.google.com/d/msg/everything-list/jFX-wTm_E_Q/dM2tcGYspfMJ as you promised to do earlier, then as soon as we are completely settled on the matter of whether events that have the same space and time coordinates in an inertial frame must have happened at the same p-time, we can go back and look at the Alice/Bob/Arlene/Bart example at https://groups.google.com/d/msg/everything-list/jFX-wTm_E_Q/pxg0VAAHJRQJwhich PROVES that a contradiction follows from your assumptions, given the premise that events with the same space and time coordinates in an inertial frame happened at the same p-time. Do you agree that if we choose a frame that preserves the real and actual symmetry of the trip that we do get EQUAL proper times between all markers on the twins respective trips? And thus that we CAN establish a 1:1 correlation of proper times in this case? The real and actual symmetry is that they have symmetrical proper accelerations as a function of proper time, but ALL frames preserve this symmetry. I agree that we are free to use a frame where their coordinate velocities and proper time as a function of coordinate time are ALSO symmetrical, but these are simply statements about coordinates, I see no reason to consider them any more real and actual than the coordinates assigned to their paths in any other frame. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Fri, Feb 28, 2014 at 12:38 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, First I would appreciate it if you didn't snip my proximate post that you are replying to... Anyway we MUST choose a frame that preserves the symmetry because remember we are trying to establish a 1:1 proper time correlation BETWEEN THE TWINS THEMSELVES (not them and anyone else), and it is only a symmetric frame that preserves the facts as EXPERIENCED BY THE TWINS THEMSELVES. ALL we need to do in my p-time theory is demonstrate that each twin can correlate his OWN proper time with that of the other twin. But you agreed earlier (in your post at https://groups.google.com/d/msg/everything-list/jFX-wTm_E_Q/PYrVLII1ClYJ ) that the idea of calling the comoving inertial frame of an observer their own frame is purely a matter of CONVENTION, not anything imposed on them by reality. So, we could easily choose a different convention--one in which each twin defines their own frame, or what they experience themselves, as the inertial frame in which they have a velocity of 0.99c along the x-axis. If they both agreed to define the facts as experienced by the twins themselves in this way, by convention, they could also agree on a 1:1 correlation between their proper times, one that would be different from the 1:1 correlation they'd get if they used the comoving frame. Do you wish to take back your earlier agreement that phrases like their own frame, their view, what they observe/experience are only by CONVENTION understood to refer to the comoving inertial frame, that this isn't something forced on us by reality? If you still agree this is a matter of convention, then it seems to me that trying to use something that's merely a matter of human linguistic convention to prove something absolute about reality is obviously silly, like trying to prove something about the essential nature of God by noting that according to the spelling conventions of English, God is dog spelled backwards. All the other frames are the views of OTHER observers, not the views of the twins themselves which is all that we need to consider to establish whether the TWINS THEMSELVES can establish a 1:1. Obviously if all observers agreed on an invariant 1:1 correlation we never would have to establish the 1:1 on a successive observer pair basis and then try to prove it transitive as I've consistently worked on doing. MY theory establishes this 1:1 correlation BETWEEN THE ACTUAL TWINS THEMSELVES on a pairwise basis, not on the basis of any invariance. Therefore it obviously uses a symmetric frame that is consistent with how those two twins experience their own and each other's realities and doesn't require input from any other frames to do that. That isn't obvious at all--I don't see how the symmetric frame reflects their experience in any way that isn't purely a matter of convention, they certainly don't experience their proper times and velocities being equal at each coordinate time if they don't CHOOSE to use a particular coordinate system. All that they directly experience in a way that doesn't depend on coordinate systems is the way that their proper acceleration varied as a function of their proper time. MY theory then attempts to prove these correlations are transitive on a pair by pair basis, not by considering all irrelevant frames and trying to establish some invariance that I agree is impossible. Does this make it clear what my theory is trying to do? The theory is based on pair wise correlations, not invariance My proof of a contradiction in your ideas about p-time doesn't consider the other frames you consider irrelevant either, it is based SOLELY on the following premises: 1. If a pair of inertial observers are at rest relative to one another, then events (like clock readings) that are simultaneous in their comoving frame are also simultaneous in p-time 2. Any two events that happen at precisely the same position and time coordinate in a particular inertial frame must be simultaneous in p-time 3. p-time simultaneity is transitive Your only response was to dispute premise #2, but subsequent discussion suggested you were originally misunderstanding what I meant by same position and time coordinate and that properly understood, you would most like agree with premise #2 after all. That's why I want you to address my last few questions about the same position and time coordinate issue at https://groups.google.com/d/msg/everything-list/jFX-wTm_E_Q/dM2tcGYspfMJwhich you promised to address earlier, but have subsequently ignored all my requests to get back to. Once again, if you continue to just ignore the requests, that indicates a lack of respect for me and for the two-way nature of discussions. Here, I'll even repost those questions to save you the time of going back through your inbox to find the original post to reply to: On Mon, Feb 24, 2014 at 6:53 PM, Edgar L. Owen edgaro...@att.netwrote: Jesse, Well, I

### Re: Block Universes

On Thu, Feb 27, 2014 at 9:25 AM, Edgar L. Owen edgaro...@att.net wrote: Jesse, I haven't answered those questions out of any disrespect or rudeness but because I was working on a new explanation which I think does specifically address and answer all of them which I present in this post. I will be happy to answer any of your questions if you think they are still relevant after reading this post which I think solves the 1:1 age correlation to your satisfaction. That's the problem, you continually come up with new arguments and explanations that you think resolve the questions I asked and therefore mean you don't need to address them, but inevitably I disagree. Please just respect my judgment about what's relevant TO ME, and answer the questions that I ask ALONGSIDE any new arguments or explanations you might want to supply. You say above I will be happy to answer any of your questions if you think they are still relevant after reading this post, so I will hold you to that by repeating a question I'd like you to answer at the end of this post. If you find any of the terminology confusing please let me know what you think it SHOULD be rather than just saying it's wrong. Twins A and B start at the same location in deep space. No acceleration, no gravitation. Their ages are obviously the same, and their age clocks are running at the same rate. They exchange flight plans and embark on their separate trips according to those flight plans. Now the only effects that will alter the rates of their age clocks are acceleration or gravitation. But each twin can continually measure the amount of acceleration or gravitation he experiences with a scale. Let's consider just the issue of accelerations in flat SR spacetime for now, since it's simpler. The problem with this statement is that although it's true each twin can measure their proper acceleration, there is no FRAME-INDEPENDENT equation in relativity for how a given acceleration affects the rates of their age clocks, the only equations dealing with clock rates and acceleration in SR deal with how changes in coordinate velocity (determined by acceleration) affect the rate a clock is ticking relative to coordinate time in some specific coordinate system. So each twin can always calculate how much his age has slowed relative to what his age WOULD HAVE BEEN had he NOT experienced any gravitation or acceleration. Let's call that his 'inertial age', the age he WOULD have been had he NOT experienced any acceleration or gravitation. I see no way to define this in any frame-independent way. The only version of this that relativity would allow you to calculate is what your age would have been at a PARTICULAR COORDINATE TIME if you had remained inertial, and you can compare that to what your age is at that SAME COORDINATE TIME given your acceleration history. But this comparison obviously gives different results in different coordinate systems. So, I don't agree with your subsequent conclusion that this allows two twins to define a 1:1 correlation in their ages in a frame-independent way. There are a number of questions I asked in the last few posts that none of your answers have addressed, but I'll restrict myself to repeating one for now: 'Also, do you understand that even for inertial observers, the idea that an observer's own rest frame can be labeled his view or taken to describe his observations is PURELY A MATTER OF CONVENTION, not something that is forced on us by the laws of nature? Physicists just don't want to have to write out in the observer's comoving inertial frame all the time, so they just adopt a linguistic convention that lets them write simpler things like from this observer's perspective or in his frame as a shorthand for the observer's comoving inertial frame. Physically there is no reason an observer can't assign coordinates to events using rulers and clocks that are moving relative to himself though, lots of real-world experiments involve measuring-instruments that move relative to the people carrying out the experiment.' Do you agree with the above paragraph? Jesse On Wednesday, February 26, 2014 10:45:51 PM UTC-5, jessem wrote: On Wed, Feb 26, 2014 at 8:52 PM, Edgar L. Owen edga...@att.net wrote: Can you agree to this at least? To repeat what I said in my second-to-last post: 'If you continue to ask me Do you agree? type questions while ignoring the similar questions I ask you, I guess I'll have to take that as a sign of contempt, in which case as I said I won't be responding to further posts of yours. Any response is better than just completely ignoring questions, even if it's something like I find your questions ambiguous or you've asked too many questions and I don't have time for them all right now, please narrow it down to one per post.' If you decide to treat me with the same basic level of respect I have treated you, rather than making a show of asking me questions while you

### Re: Block Universes

On Thu, Feb 27, 2014 at 2:38 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, First the answer to your question at the end of your post. Yes, of course I agree. Again that's just standard relativity theory. However as you point out by CONVENTION it means the observer's comoving inertial frame which is the way I was using it. Thanks, it seemed like you might have been suggesting there was some natural truth to calculations done in the comoving frame of two obserervers at rest relative to each other, even though they could equally well agree to calculate things from the perspective of a totally different frame. Now to your replies to my post beginning with your first paragraph. Certainly there are equations that do what you say they do, but I don't see why what I say isn't correct based on that. Why do you claim it is impossible to just take proper acceleration and calculate what my age would have been if there was not any proper acceleration? I don't claim it's impossible, just that it can only be done relative to a particular frame. I can make statements like I am now 30, but in frame A, if I hadn't accelerated I would now be 20 and I am now 30, but in frame B, if I hadn't accelerated I would now be 25. An observer knows what his proper acceleration is, and he knows how much various accelerations are slowing his proper time relative to what it would be if those accelerations didn't happen. Slowing his proper time only has meaning relative to a particular frame, there is no frame-independent sense in which clocks slow down (or speed up) due to acceleration in relativity. He has a frame independent measure of acceleration. He knows that particular acceleration will slow his proper time by 1/2 so he can define and calculate an 'inertial time' whose rate is 2x his proper rate. Given the exact same proper acceleration, there may be one frame A where at the end of the acceleration his clock has slowed by 1/2 (relative to the time coordinate of that frame), and another frame B where it has slowed by 1/3, and even another frame where it has *sped up* by a factor of 10. Do you disagree? You seem to think it would be necessary to MEASURE THIS FROM SOME FRAME for the concept to be true. It's not an observable measure, it's the CALCULATION of a useful variable. Therefore there is NO requirement that it's measurable in any frame because it's a frame independent concept, a calculation rather than an observable. Calculations are always calculations of the values of particular numerical quantities, like the rate a clock is ticking. So, what matters is whether the quantity in question is frame-dependent (like velocity, or rate of clock ticking) or frame-independent (like proper time at a specific event on someone's worldine), there is nothing inherent in the notion of calculations that make them frame-independent. Also, *all* calculated quantities in relativity can also be observables--it's straightforward to observe frame-independent quantities like proper time (just look at the clock the observer carries), and frame-dependent ones can also be observed if you have a physical grid of rulers and coordinate clocks as I have described before (for example, to find the rate a clock is ticking relative to a coordinate system, you look at the time T1 it reads as it passes next to a coordinate clock that reads t1, and the time T2 it reads as it passes next to another coordinate clock that reads t2, and then you can just define the average rate over that interval as [T2 - T1]/[t2 - t1], and if the difference between T2 and T1 approaches 0 this approaches the *instantaneous* rate at T1). Therefore I don't see any reason to accept your criticism in this paragraph. If you disagree, which I'm sure you will, then explain why this concept of inertial time is not frame independent and valid. Perhaps a clear example would help? If you disagree with my statement above that different frames can disagree on the amount that a clock slowed down (or sped up) after a given proper acceleration, I can give you a numerical example. Another way to approach this is do you deny that if we drop a coordinate grid on an area of EMPTY space that the coordinate clocks at the grid intersections all run at the same rate? And if not, why? Are you talking about an inertial coordinate grid of rigid rulers, or an arbitrary non-inertial coordinate grid where we can imagine different grid points connected by rubbery rulers that can stretch and compress over time? In the simpler case of an inertial grid, obviously all inertial coordinate clocks tick at the same rate relative to any other inertial coordinate system, though not necessarily relative to an arbitrary non-inertial system. And the clocks of an arbitrary non-inertial coordinate system need not tick at a constant rate relative to inertial systems. And don't start making up other frames on me here. Just compare the proper times of those

### Re: Block Universes

On Thu, Feb 27, 2014 at 4:05 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, Remember we are talking ONLY about PROPER TIMES, or actual ages. These DO NOT HAVE any MEANING IN OTHER FRAMES than that of the actual frame of the observer in question. No, you couldn't be more wrong about that last statement. Any physics textbook will tell you that the proper time between two events on a worldline is a frame-independent quantity that can be calculated in ANY frame, in fact this is one of the most important frame-independent quantities in both special and general relativity (for example, in general relativity the curvature of spacetime is defined in terms of the metric which gives proper time along all possible timelike worldlines in the spacetime, and proper distance along all possible spacelike worldlines). A simple example: say in Alice's rest frame, there are two markers at rest in this frame 20 light-years apart, and Bob moves inertially from one marker to the other a velocity of 0.8c in this frame. What is the proper time on Bob's worldline between passing the first marker and passing the second? In Alice's frame we could calculate this by first noting it should take 20/0.8 = 25 years of coordinate time in this frame for Bob to get from one to the other, and then the time dilation equation tells us that if he's moving at 0.8c his clock should be slowed by a factor of sqrt(1 - 0.8^2) = 0.6 in this frame, so Bob's own clock should tick forward by 25*0.6 = 15 years between passing the first marker and the second. That is BOB'S PROPER TIME, AS CALCULATED IN ALICE'S REST FRAME. You could of course calculate the proper time in Bob's rest frame too. In this case, you have to take into account length contraction--the markers are moving at 0.8c relative to Bob's frame, so if the distance between them was 20 light-years in their own rest frame, in Bob's frame the distance between them is shortened by a factor of sqrt(1 - 0.8^2) = 0.6, so in Bob's frame the second marker is 20*0.6 = 12 light-years away at the moment he is passing the first marker. Thus, if the second marker is moving towards him at 0.8c, it will take 12/0.8 = 15 years of coordinate time in this frame to reach him after the first marker passed him. And since he is at rest in this frame, his clock ticks at the same rate as coordinate time, so his clock should also tick foward by 15 years between passing the first marker and passing the second. That is BOB's PROPER TIME, AS CALCULATED IN BOB'S REST FRAME, and you can see that we get exactly the same answer as when we calculated his proper time using Alice's rest frame. After looking over this example, please tell me if you AGREE or DISAGREE that in relativity the proper time between two specific events on a worldline can be calculated using any frame we wish (in the manner above), and we'll always get the same answer regardless of what frame we use. So your comments that an observer's age will be measured differently in other frames, while obviously true, is NOT the observer's PROPER AGE or PROPER TIME. Every observer has one and only one proper age, that is his proper age to himself, NOT to anyone else, not in any other frame. Every observer has a proper age at any specific event on their worldine, like the event of Bob passing one of the markers in my example above. But this proper age is not associated with any particular frame, it's a frame-independent quantity that can be calculated in whatever frame you wish, and no matter what frame you use to perform the calculations you'll always get exactly the same answer. That holds for all your comments about age effects of acceleration being different in different frames. Of course they can be but that is NOT PROPER ACTUAL AGE. But you are not pointing to a specific event on his worldline and asking his proper age at that point, you are asking what his age *would* have been if he hadn't accelerated. This involves looking at TWO worldlines--one of the actual person who had done some acceleration, and another hypothetical worldline he would have had if he had not accelerated (this need not be purely hypothetical, you could imagine he had a twin who was moving alongside him before he accelerated, but continued to move inertially when he accelerated). And you're asking which event on the second inertial worldline lines up with some specific event on the worldline that experienced acceleration (like the event of his accelerometer first showing that he has stopped accelerating and is experiencing 0 G-force once again). It's impossible to answer that question in relativity without picking a specific frame with a specific definition of simultaneity, which allows us to match up the event on the non-inertial worldline with some specific event on the inertial worldline, and then calculate the age on the inertial worldline at that event. So I have to disregard all those comments because they don't apply to PROPER TIMES OR ACTUAL

### Re: Block Universes

On Thu, Feb 27, 2014 at 4:49 PM, Jesse Mazer laserma...@gmail.com wrote: A simple example: say in Alice's rest frame, there are two markers at rest in this frame 20 light-years apart, and Bob moves inertially from one marker to the other a velocity of 0.8c in this frame. What is the proper time on Bob's worldline between passing the first marker and passing the second? In Alice's frame we could calculate this by first noting it should take 20/0.8 = 25 years of coordinate time in this frame for Bob to get from one to the other, and then the time dilation equation tells us that if he's moving at 0.8c his clock should be slowed by a factor of sqrt(1 - 0.8^2) = 0.6 in this frame, so Bob's own clock should tick forward by 25*0.6 = 15 years between passing the first marker and the second. That is BOB'S PROPER TIME, AS CALCULATED IN ALICE'S REST FRAME. You could of course calculate the proper time in Bob's rest frame too. In this case, you have to take into account length contraction--the markers are moving at 0.8c relative to Bob's frame, so if the distance between them was 20 light-years in their own rest frame, in Bob's frame the distance between them is shortened by a factor of sqrt(1 - 0.8^2) = 0.6, so in Bob's frame the second marker is 20*0.6 = 12 light-years away at the moment he is passing the first marker. Thus, if the second marker is moving towards him at 0.8c, it will take 12/0.8 = 15 years of coordinate time in this frame to reach him after the first marker passed him. And since he is at rest in this frame, his clock ticks at the same rate as coordinate time, so his clock should also tick foward by 15 years between passing the first marker and passing the second. That is BOB's PROPER TIME, AS CALCULATED IN BOB'S REST FRAME, and you can see that we get exactly the same answer as when we calculated his proper time using Alice's rest frame. Incidentally, for two events E1 and E2 on the worldline of an inertial clock (like the events of Bob passing each marker), there is also a simple formula for calculating the proper time the clock ticks between those events, using the coordinates of any frame you like. That is: (proper time between E1 and E2)^2 = (coordinate time between E1 and E2)^2 - (1/c^2)*(coordinate distance between E1 and E2)^2 Or using more common notation, dtau^2 = dt^2 - (1/c^2)*dx^2 If you use units where c = 1, like years for time and light-years for distance, this reduces to: dtau^2 = dt^2 - dx^2 For example, in Alice's frame we have dt = 25 years, and dx = 20 light-years, so dtau^2 = 25^2 - 20^2 = 625 - 400 = 225, so dtau is the square root of 225, or 15. Likewise, in Bob's frame we have dt = 15 years (which you could derive using the Lorentz transformation if you knew the coordinates of passing each marker in Alice's frame), and dx = 0, which again gives dtau^2 = 225 and therefore dtau = 15. This formula is the spacetime analogue of the Pythagorean formula in Euclidean geometry, which tells you that if you have a line segment that has some length ds that you want to calculate, then if you use any cartesian coordinate system to define the x and y coordinates of its endpoints, so you can find dx and dy between the endpoints, then ds^2 = dx^2 + dy^2. Just as the length of a line segment will have an answer that is the same regardless of how you orient your Cartesian coordinate axes (dx and dy may change depending on the axes, but ds will always be the same), so the proper time between two events on a worldline has an answer that is the same regardless of what inertial frame you use (dx and dt can vary, but dtau will always be the same)--both are coordinate-independent quantities, and both are understood to reflect the geometry of the space/spacetime in which they are defined. Jesse -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.

### Re: Block Universes

On Thu, Feb 27, 2014 at 6:43 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, My understanding of the first part of your reply is though proper time is ONLY one's reading of one's own clock (as I stated) it IS possible for any other observer to calculate that proper time and always come up with the same answer. Is that correct? For a given clock C, it is possible for any observer to calculate the proper time between events ON C'S OWN WORLDLINE, and everyone will get the same answer (it is frame-invariant). But what is NOT frame-invariant is the answer to a question like what is the proper time on that distant clock RIGHT NOW, at the same moment that my own clock shows some specific time T--in that case you aren't talking about a specific event on C's worldline, you're talking about a specific event on your worldline (the event of your clock showing time T), and asking which event on C's worldline is simultaneous with that. Since simultaneity is frame-dependent in relativity, there is no frame-invariant answer to this second type of question. If so that's precisely what I've been claiming all along! That it's always possible for any observer to calculate any other observer's PROPER TIME. Why did I get the strong impression you were claiming that wasn't so from your previous replies? That is precisely the whole crux of my case, and precisely what I've been claiming In my view that is exactly what is necessary to establish a 1:1 correlation between proper times. If everyone can always calculate everyone's proper times including their own in an UNAMBIGUOUS INVARIANT WAY then why isn't it possible to establish a 1:1 correlation between them? Please give me a clear and simple proof that it's not By unambiguous invariant way, which of these do you mean? 1. If they all agree to use a particular reference frame to define frame-dependent things like simultaneity and velocity, then they can agree on which proper times on each worldline are simultaneous, giving a 1:1 correlation. 2. They have a way to define a 1:1 correlation between proper times that does NOT depend on agreeing to use any particular reference frame. Please tell me whether you would select 1 or 2 (or some third option that is somehow different than either one). I'm not sure whether it's necessarily relevant here but note that the event markers that define proper ages are already actual physical worldline event points defined by the earth's orbit and rotation. But we have been discussing scenarios involving observers zipping around in space, so events on Earth would not be at the same point in spacetime as events on their own worldlines. So the very definition of a proper age is already IN TERMS OF worldline markers. We don't have to specify new markers to make things work. Proper time is ALREADY NECESSARILY defined in terms of event markers such as physical clock ticks. We don't need any new ones. I agree that clock ticks can count as markers, but sometimes you're dealing with problems where you want to calculate what a clock reading at a point on some observer's worldline will be without knowing it in advance. If you have a network of coordinate clocks, you can also use readings on coordinate clocks at the moment the traveling observer passes right next to them as event markers, and ask questions like what is this observer's proper time at a coordinate time of t, i.e. at the moment the coordinate clock he's right next to at that moment reads t. Do you also agree that proper time RATES are calculable by other observers and invarian? Not just the times, but the rates as well? No, there is no frame-invariant notion of clock rate in relativity. The only way to talk about rates is to look at the rate a clock is ticking relative to coordinate time in some coordinate system, and obviously this can differ from one coordinate system to another. Jesse On Thursday, February 27, 2014 4:49:17 PM UTC-5, jessem wrote: On Thu, Feb 27, 2014 at 4:05 PM, Edgar L. Owen edga...@att.net wrote: Jesse, Remember we are talking ONLY about PROPER TIMES, or actual ages. These DO NOT HAVE any MEANING IN OTHER FRAMES than that of the actual frame of the observer in question. No, you couldn't be more wrong about that last statement. Any physics textbook will tell you that the proper time between two events on a worldline is a frame-independent quantity that can be calculated in ANY frame, in fact this is one of the most important frame-independent quantities in both special and general relativity (for example, in general relativity the curvature of spacetime is defined in terms of the metric which gives proper time along all possible timelike worldlines in the spacetime, and proper distance along all possible spacelike worldlines). A simple example: say in Alice's rest frame, there are two markers at rest in this frame 20 light-years apart, and Bob moves inertially from one marker

### Re: Block Universes

On Wed, Feb 26, 2014 at 2:31 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, You continue to quibble over terminology to avoid engaging the real issues. Of course by 'view' I DO mean the actual equations in terms of a coordinate system with origin at a particular observer. There is OF COURSE a single set of equations that describes that view. There are a single set of equations for any particular coordinate system, but my point is that for non-inertial observers or observers in curved spacetime, talking about an observer's view is ill-defined because there is no convention about which coordinate system to label as the view of a given observer. Even if you specify that you want a coordinate system with origin at a particular observer, there are an infinite number of DIFFERENT non-inertial coordinate systems you could come up with that would have the property that the observer is always at the origin, each with a different set of equations. I asked about this issue specifically in the second question from my last post, which you didn't answer: '--If you don't disagree with the statement above, do you disagree with my statement that there's no specific coordinate system that is understood by physicists to represent a particular observer's view or perspective in general relativity, so that if you just talk about equations used by observer A without specifying a coordinate system, physicists wouldn't know what you were talking about?' Could you please just just quote my questions and answer them specifically in turn, as I always do with yours, rather than just sort of summarizing what you think my main points are and addressing them in a broad manner? Answers to your next question: Yes, of course the OBSERVABLES are based on some coordinate system, but you can't seem to get it through your head that any observer A who observes another observer B can also know the equations governing how that observer B observes A himself. I'm not sure which question you are responding to here, you say next question but it seems like this is actually a response to my FIRST question (with no response given to any of the others), namely: '--Do you disagree that equations that observer A uses to calculate the observables of any other observer B are always based on A using some particular coordinate system? (if so, can you give an example of an equation that could be used to make such a calculation which would not depend on any specific coordinate system, but which would still be observer-dependent in some sense, so it would still be meaningful to identify this equation specifically with observer A?) ' You didn't really respond to any of the subsequent three questions with dashes before them, as far as I can see, although you did respond to the question in my last paragraph. Can you please go back and respond to the middle 3 questions? Do you deny that? I deny that there is any single set of equations governing how observer B observes A himself, if B is not an inertial observer in flat spacetime. If he's not, then as I said, there's no convention in relativity that says that any particular coordinate system should be interpreted as belonging to B. If you specify in detail what coordinate systems you want A and B to use to perform calculations (or if both of them are inertial in flat spacetime, so it's taken as read that they each use their own rest frame), then of course A can figure out what B would calculate and B could figure out what A would calculate. Also, do you understand that even for inertial observers, the idea that an observer's own rest frame can be labeled his view or taken to describe his observations is PURELY A MATTER OF CONVENTION, not something that is forced on us by the laws of nature? Physicists just don't want to have to write out in the observer's comoving inertial frame all the time, so they just adopt a linguistic convention that lets them write simpler things like from this observer's perspective or in his frame as a shorthand for the observer's comoving inertial frame. Physically there is no reason an observer can't assign coordinates to events using rulers and clocks that are moving relative to himself though, lots of real-world experiments involve measuring-instruments that move relative to the people carrying out the experiment. I'll skip now to the point you make in your last paragraph responding to my symmetric trip case: Your comments here are true (more standard relativity) but irrelevant. Why, because the point of the symmetric trip argument is TO ESTABLISH a 1:1 correlation ONLY BETWEEN THE PROPER TIMES OF A and B, not any of the any other coordinate systems you attempt to drag into the discussion to obfuscate things. It isn't a 1:1 correlation between the proper times of A and B without qualification, it's a 1:1 correlation between the proper times of A and B RELATIVE TO THEIR REST FRAME. If you use a different frame, there is a different 1:1

### Re: Block Universes

On Wed, Feb 26, 2014 at 4:50 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, A symmetric trip is defined in terms of the symmetric view of two observers A and B OF EACH OTHER IN TERMS OF THEIR OWN COMOVING COORDINATE SYSTEMS. If they aren't inertial observers in flat spacetime--and they can't be inertial if they depart from one another and then reunite later--then their own comoving coordinate systems is a COMPLETELY UNDEFINED PHRASE. There are an infinite number of DIFFERENT non-inertial coordinate systems you could design in which they remain fixed at the spatial origin of the coordinate system (so each one is comoving in that sense), and there is no convention recognized by physicists that their own comoving coordinate system would refer to any particular one of these different possible systems. DO YOU DISAGREE? I have asked variants of this question several times now, once again you seem to be back to your old habit of refusing to answer simple agree/disagree questions I ask you, even after you have demanded that I answer a number of yours. As I said before, this is quite rude behavior, and if you aren't interested in civil reasoned discourse where you actually address the other person's arguments and questions, rather than just haranguing them with the same assertions and expressing incredulity that they could fail to be convinced, then there's obviously no point to any further exchanges between us. The proper times of both twins A and B have a 1:1 correlation and are equal at start and finish of the trip. Although it's true in a frame-independent sense that their proper times are equal at the end when they reunite, any 1:1 correlation of proper times DURING the trip can only be defined relative to a particular coordinate system, and there's no physical reason why using the system where their velocities are symmetrical is more correct than using any other coordinate system. As I just said in my last post: 'It isn't a 1:1 correlation between the proper times of A and B without qualification, it's a 1:1 correlation between the proper times of A and B RELATIVE TO THEIR REST FRAME. If you use a different frame, there is a different 1:1 correlation between the proper times of A and B, RELATIVE TO THAT OTHER FRAME. Nothing in the phrase 1:1 correlation between the proper times of A and B by itself tells us what frame to use.' Do you disagree with the above? PROPER clocks always run at the same rate in the same relativistic conditions. Run at the same rate has no coordinate-independent meaning in relativity. You won't find any relativity textbook that defines the rate of a clock in any way except relative to a particular choice of coordinate system (assuming we're not just talking about visual rates based on light signals). Do you disagree that the above is true ACCORDING TO MAINSTREAM RELATIVITY THEORY AS UNDERSTOOD BY PHYSICISTS? (if you agree, but you think that YOU have discovered a new coordinate-independent concept of clock rate that physicists have failed to recognize, then please specify that). The laws of nature do not change during the trip. The relativistic conditions of both PROPER clocks thus DO run at the same rates DURING the trip. Forget everything else but the PROPER clocks because it's irrelevant to the case. Proper time deals only with clock readings at specific locally-defined events on their worldlines (like the time on their clock at the moment they pass next to some marker in space), there is no corresponding notion of a coordinate-independent proper rate of a clock. Again, the rate a clock is ticking is an INHERENTLY coordinate-dependent notion in mainstream relativity theory. Thus there will be a 1:1 correspondence of PROPER clock times DURING THE TRIP. This is NOT any SINGLE FRAME VIEW. You continue to try to analyze it from some single frame. IT CAN'T BE DONE. This is a logical consequence of the laws of relativity, NOT THE VIEW FROM ANY SINGLE FRAME. You say logical consequence, but again it is just an assertion, not an actual logical demonstration of HOW the laws of relativity lead to this conclusion. If you can't even get this simple fact I see no reason to proceed. It seems to me that your stated agenda of not accepting p-time prevents you from thinking objectively here. No mainstream physicist would agree with this simple fact, and that has nothing to do with whether they prefer block time or presentism or have no opinion on the matter. They all recognize that clock rates, and correspondences between proper times of clocks separated in space, are inherently frame-dependent. In any case, a simple way to proceed would involve just doing me the courtesy of answering my questions, so we can better pinpoint the first point on which we are in disagreement, and see if this is a matter of disagreeing about how things work in mainstream relativity theory (in which case I can look for references to support my claims, and we

### Re: Block Universes

On Wed, Feb 26, 2014 at 6:46 PM, Edgar L. Owen edgaro...@att.net wrote: Jesse, O, for God's sakes. Just take a SINGLE INERTIAL coordinate system centered at some point in deep space from which they both depart, travel symmetrically away from RELATIVE TO THAT SINGLE COORDINATE SYSTEM and then meet back up at. That addresses all your concerns. The whole trip is symmetric, the twins' proper times will be in a 1:1 correlation at all times from beginning to end. Both twins agree their proper clocks run at the exact same rates, not because they observe them but because they understand relativity. Do you agree? Of course not I agree that there is a 1:1 correlation between their proper times RELATIVE TO THAT INERTIAL COORDINATE SYSTEM (in this case, the correlation is such that a given proper time time T of one is correlated with the SAME proper time T of the other, according to that coordinate system's definition of simultaneity). Likewise, their proper clocks run at the exact same rates RELATIVE TO THAT INERTIAL COORDINATE SYSTEM (i.e. both have the same function for proper time as a function of coordinate time). But so what? Their proper times have a different 1:1 correlation relative to some other inertial coordinate system (in which the proper time T for one is correlated with a DIFFERENT proper time T' for the other--this is still a 1:1 correlation in the sense that a specific proper time for one is correlated to a specific proper time of the other), and their proper clocks run at different rates relative to this other coordinate system (they have different functions for proper time as a function of coordinate time). So this is of no help in deciding which of the VARIOUS possible 1:1 correlations in their proper times represent the proper times that share the same frame-independent present moment, even if such a thing exists (as you know I am skeptical about such a thing, but I don't totally rule it out as a possibility). Please tell me if you agree or disagree that all statements about 1:1 correlations of proper times and ratios of rates only have meaning RELATIVE TO SOME COORDINATE SYSTEM (in mainstream relativity theory anyway, leaving aside ideas which aren't part of relativity like p-time), and that all inertial coordinate systems are considered equally valid in special relativity. If you continue to ask me Do you agree? type questions while ignoring the similar questions I ask you, I guess I'll have to take that as a sign of contempt, in which case as I said I won't be responding to further posts of yours. Any response is better than just completely ignoring questions, even if it's something like I find your questions ambiguous or you've asked too many questions and I don't have time for them all right now, please narrow it down to one per post. Jesse Nevertheless, it's correct and the rest of what I said follows... Edgar On Wednesday, February 26, 2014 3:40:36 PM UTC-5, jessem wrote: On Wed, Feb 26, 2014 at 2:31 PM, Edgar L. Owen edga...@att.net wrote: Jesse, You continue to quibble over terminology to avoid engaging the real issues. Of course by 'view' I DO mean the actual equations in terms of a coordinate system with origin at a particular observer. There is OF COURSE a single set of equations that describes that view. There are a single set of equations for any particular coordinate system, but my point is that for non-inertial observers or observers in curved spacetime, talking about an observer's view is ill-defined because there is no convention about which coordinate system to label as the view of a given observer. Even if you specify that you want a coordinate system with origin at a particular observer, there are an infinite number of DIFFERENT non-inertial coordinate systems you could come up with that would have the property that the observer is always at the origin, each with a different set of equations. I asked about this issue specifically in the second question from my last post, which you didn't answer: '--If you don't disagree with the statement above, do you disagree with my statement that there's no specific coordinate system that is understood by physicists to represent a particular observer's view or perspective in general relativity, so that if you just talk about equations used by observer A without specifying a coordinate system, physicists wouldn't know what you were talking about?' Could you please just just quote my questions and answer them specifically in turn, as I always do with yours, rather than just sort of summarizing what you think my main points are and addressing them in a broad manner? Answers to your next question: Yes, of course the OBSERVABLES are based on some coordinate system, but you can't seem to get it through your head that any observer A who observes another observer B can also know the equations governing how that observer B observes A himself. I'm not sure which