Re: Philip Ball, MWI skeptic
Russell Standish wrote: On Fri, Mar 06, 2015 at 02:20:21PM +1100, Bruce Kellett wrote: Russell Standish wrote: On Thu, Mar 05, 2015 at 04:05:07PM +1100, Bruce Kellett wrote: There is mathematically no way to choose a set of vectors that are simulatneously eigenvalues of both operators. That comes from the Hilbert space structure, which in turn is a consequence of invoking an observer and Kolmogorov's axioms. It is because the position and momentum operators do not commute. I don't see how this is a consequence of invoking an observer. Bruce Then you need to study my derivation. The Hilbert space structure is a consequence of two simple assumptions about what it is to be an observer embedded in an ensemble of universes, plus Kolmogorov's axioms. Operators in Hilbert space in general do not commute. Any pair of noncommuting operators will not allow a basis set that is simultaneously a set of eigenvectors of both operators, as you say. That the operators corresponding to the classical concepts of position and momentum spefically don't commute does lie outside my derivation (the so called correspondence principle). However, I like Vic Stenger's answer to that question, which is based on Emmy Noether's ideas. Brent specifically referred to simultaneous position amd momentum eigenstates, so my response was appropriate. The fact that these operators do not commute is the basis of Bohr's principle of complementarity -- nothing to do with the correspondence principle. Correspondence principle is the identification x<->X, p<->i/hbar d/dx. That's what I was talking about. Although looking at Wikipedia entry for the correspondence principle, they're talking more about the Ehrenfest theorem stuff, ie the classical limit of quantum systems, which is not the same things at all. Wikipedia agrees with the way I was taught QM -- the Correspondence Principle was all about agreeing with classical mechanics in the appropriate limit. For Bohr's original atomic models, he required agreement with the classical results for large quantum numbers. I think the Correspondence Principle can usefully be used in a wider context than this. Bruce Oh dear - I must have got the term from somewhere, but can't find who I might have picked that up from. It passed a few different peer reviews without being picked up... The trouble I find with Vic Stenger's derivations in QM is that they only work because he knows the answer. He gives a useful compendium of results in terms of symmetry principles, but there are too many other possibilities for this to work as a rigorous derivation. Fair enough. That's the feeling I get too :). -- 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: Philip Ball, MWI skeptic
On Fri, Mar 06, 2015 at 02:20:21PM +1100, Bruce Kellett wrote: > Russell Standish wrote: > >On Thu, Mar 05, 2015 at 04:05:07PM +1100, Bruce Kellett wrote: > >>>There is mathematically no way to choose a set of vectors that are > >>>simulatneously eigenvalues of both operators. That comes from the > >>>Hilbert space structure, which in turn is a consequence of invoking an > >>>observer and Kolmogorov's axioms. > >>It is because the position and momentum operators do not commute. I > >>don't see how this is a consequence of invoking an observer. > >> > >>Bruce > > > >Then you need to study my derivation. The Hilbert space structure is a > >consequence of two simple assumptions about what it is to be an > >observer embedded in an ensemble of universes, plus Kolmogorov's > >axioms. > > > >Operators in Hilbert space in general do not commute. Any pair of > >noncommuting operators will not allow a basis set that is > >simultaneously a set of eigenvectors of both operators, as you say. > > > >That the operators corresponding to the classical concepts of position > >and momentum spefically don't commute does lie outside my derivation (the so > >called correspondence principle). However, I like Vic Stenger's answer > >to that question, which is based on Emmy Noether's ideas. > > Brent specifically referred to simultaneous position amd momentum > eigenstates, so my response was appropriate. The fact that these > operators do not commute is the basis of Bohr's principle of > complementarity -- nothing to do with the correspondence principle. > Correspondence principle is the identification x<->X, p<->i/hbar d/dx. That's what I was talking about. Although looking at Wikipedia entry for the correspondence principle, they're talking more about the Ehrenfest theorem stuff, ie the classical limit of quantum systems, which is not the same things at all. Oh dear - I must have got the term from somewhere, but can't find who I might have picked that up from. It passed a few different peer reviews without being picked up... > The trouble I find with Vic Stenger's derivations in QM is that they > only work because he knows the answer. He gives a useful compendium > of results in terms of symmetry principles, but there are too many > other possibilities for this to work as a rigorous derivation. > Fair enough. That's the feeling I get too :). -- Prof Russell Standish Phone 0425 253119 (mobile) Principal, High Performance Coders Visiting Professor of Mathematics hpco...@hpcoders.com.au University of New South Wales http://www.hpcoders.com.au Latest project: The Amoeba's Secret (http://www.hpcoders.com.au/AmoebasSecret.html) -- 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: Philip Ball, MWI skeptic
Russell Standish wrote: On Thu, Mar 05, 2015 at 04:05:07PM +1100, Bruce Kellett wrote: There is mathematically no way to choose a set of vectors that are simulatneously eigenvalues of both operators. That comes from the Hilbert space structure, which in turn is a consequence of invoking an observer and Kolmogorov's axioms. It is because the position and momentum operators do not commute. I don't see how this is a consequence of invoking an observer. Bruce Then you need to study my derivation. The Hilbert space structure is a consequence of two simple assumptions about what it is to be an observer embedded in an ensemble of universes, plus Kolmogorov's axioms. Operators in Hilbert space in general do not commute. Any pair of noncommuting operators will not allow a basis set that is simultaneously a set of eigenvectors of both operators, as you say. That the operators corresponding to the classical concepts of position and momentum spefically don't commute does lie outside my derivation (the so called correspondence principle). However, I like Vic Stenger's answer to that question, which is based on Emmy Noether's ideas. Brent specifically referred to simultaneous position amd momentum eigenstates, so my response was appropriate. The fact that these operators do not commute is the basis of Bohr's principle of complementarity -- nothing to do with the correspondence principle. The trouble I find with Vic Stenger's derivations in QM is that they only work because he knows the answer. He gives a useful compendium of results in terms of symmetry principles, but there are too many other possibilities for this to work as a rigorous derivation. Bruce -- 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: Philip Ball, MWI skeptic
On Thu, Mar 05, 2015 at 07:55:42PM +0100, Bruno Marchal wrote: > > On 05 Mar 2015, at 06:12, Russell Standish wrote: > > >On Wed, Mar 04, 2015 at 06:06:35PM +0100, Bruno Marchal wrote: > >> > >>My opinion has not much changed since the last critics. It is a very > >>nice derivation, but too much quick at some step, assuming the > >>reals, derivative, effectivity, etc. It go in the right conceptual > >>direction, (from the comp perspective). > > > >The reals come with Kolmogorov's axioms. They also appear as part of > >measure theory. Perhaps it can be done without invoking the reals, > >perhaps not. > > Plausibly. On any rich enough topological group I presume. > > Why information must be preserved between observer moments? > Information can only change through learning or forgetting. In a multiverse (or plenitude), if I learn something, then there must be other "mes" that learn the complementary facts. If I forget something, then my observer moment is merged with others. This is a measure preserving property. It is also an information preserving property. The information contained in the ensemble of outcomes to a measurement must be precisely as what it was prior to measurement. Similarly going from one measurement event to the next. > You are quick in making the observer moments into a complex vector > space (your refer to 4.5, in your appendix, but you are quick in > 4.5). > > It is interesting, but if you make things formal, there are still > many assumptions, including the existence of the measure. > Yes - that is indeed an assumption. I know where you're going, given that you've criticised on that point by Delahaye. I justify this by Anthropic reasoning, but agree this should be explored further. > It might help in the comp derivation of physics. > > Just now, I am not sure I understand the derivation of the square of > the amplitude, but I will (re)read this more at ease when I have > more time, and let you know. > > Hmm... What do you mean by uniform measure on infinite set? > Every element has the same weight as any other. It works best for set having an infinite number of points between any pair (assuming some sort of partial ordering). On something like the integers, every subset will zero uniform measure, I believe. Maybe that's also true of the rationals... > > > >The only place a derivative appears is at D.13. IIUC, derivatives are > >well defined operators for any sort of timescale, not just continuous > >ones. In discrete timescales, the derivative is just a difference > >operator IIRC. > > OK, but why a derivative? Why the reals ? > Real time is not assumed. But it helps to make contact with the traditional Schroedinger equation. On some other timescale, Schroedinger's equation must be generalised. > > > > > >Effectivity? > > > You require that phi(t') follows deterministically from phi(t) when > t' < t. (page 221). > Lewontin's requirement is a bit like forcing the measure, which is > not obvious a priori in the digital perspective. > It might works, but needs deeper justifications. > > Lewontin's criteria is somewhat more of an inspiration than a direct requirement. Heritability entails a preservation of information as the system evolves. Variation and Selection is akin to the PROJECTION postulate. -- Prof Russell Standish Phone 0425 253119 (mobile) Principal, High Performance Coders Visiting Professor of Mathematics hpco...@hpcoders.com.au University of New South Wales http://www.hpcoders.com.au Latest project: The Amoeba's Secret (http://www.hpcoders.com.au/AmoebasSecret.html) -- 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: Philip Ball, MWI skeptic
On Thu, Mar 05, 2015 at 04:05:07PM +1100, Bruce Kellett wrote: > > > >There is mathematically no way to choose a set of vectors that are > >simulatneously eigenvalues of both operators. That comes from the > >Hilbert space structure, which in turn is a consequence of invoking an > >observer and Kolmogorov's axioms. > > It is because the position and momentum operators do not commute. I > don't see how this is a consequence of invoking an observer. > > Bruce > Then you need to study my derivation. The Hilbert space structure is a consequence of two simple assumptions about what it is to be an observer embedded in an ensemble of universes, plus Kolmogorov's axioms. Operators in Hilbert space in general do not commute. Any pair of noncommuting operators will not allow a basis set that is simultaneously a set of eigenvectors of both operators, as you say. That the operators corresponding to the classical concepts of position and momentum spefically don't commute does lie outside my derivation (the so called correspondence principle). However, I like Vic Stenger's answer to that question, which is based on Emmy Noether's ideas. -- Prof Russell Standish Phone 0425 253119 (mobile) Principal, High Performance Coders Visiting Professor of Mathematics hpco...@hpcoders.com.au University of New South Wales http://www.hpcoders.com.au Latest project: The Amoeba's Secret (http://www.hpcoders.com.au/AmoebasSecret.html) -- 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: Philip Ball, MWI skeptic
On 6 March 2015 at 06:22, Bruno Marchal wrote: > > On 04 Mar 2015, at 21:36, LizR wrote: > > On 5 March 2015 at 04:37, Bruno Marchal wrote: > >> >> So it is not the state of the halting problem which are physical, it is >> the physical which needs to be redefined in term of a measure (or the logic >> of the measure one, of that measure) on the halting programs. >> >> Yes, that's what I was trying to say, in my roundabout way. Using > "physical" confuses the matter, if you'll pardon the pun. > > >> There is no reversal in Tegmark. He misses the mind-body problem in >> general, and the computationalist one in particular. >> > > Yes, he is in the interesting position of being what might be called a > "mathematical materialist" - deriving the material world from maths and > finding he still has the mind-body problem, which he then solves by saying > it isn't a problem (as for example Dennett does. Of course he may be > right...) > > He may be right? Well, even if right, he has to prove it, and by > definition, that is the mind-body problem! > Yes, you clever logic chopper! But that doesn't mean the problem can't be solved by showing that it's only an apparent problem. I imagine Dennett would say something like this: "Consciousness is a complex illusion generated as a sort of user interface between the brain and the world. It is no more fundamental to reality than the pattern of pixels on my screen is a real desktop. It is an attempt to explain how we have experiences that is based on Cartesian dualism, while science tells us that the world is made of matter, energy, etc - there are no ghosts in the machine - eventually the idea of consciousness being anything more than what I have said will look as outdated as elan vital and phlogiston." Of course this doesn't address the consequencs of taking this view to its logical extreme as Bruno has done (or I should say claims to have done, since I haven't been able to follow the whole argument). I'd be interested to hear what DCD would have say about comp. -- 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: Philip Ball, MWI skeptic
On Thu, Mar 5, 2015 at 12:55 PM, Bruno Marchal wrote: > > On 05 Mar 2015, at 06:12, Russell Standish wrote: > > On Wed, Mar 04, 2015 at 06:06:35PM +0100, Bruno Marchal wrote: >> >>> >>> My opinion has not much changed since the last critics. It is a very >>> nice derivation, but too much quick at some step, assuming the >>> reals, derivative, effectivity, etc. It go in the right conceptual >>> direction, (from the comp perspective). >>> >> >> The reals come with Kolmogorov's axioms. They also appear as part of >> measure theory. Perhaps it can be done without invoking the reals, >> perhaps not. >> > > Plausibly. On any rich enough topological group I presume. > > Why information must be preserved between observer moments? > > You are quick in making the observer moments into a complex vector space > (your refer to 4.5, in your appendix, but you are quick in 4.5). > > It is interesting, but if you make things formal, there are still many > assumptions, including the existence of the measure. > > It might help in the comp derivation of physics. > > Just now, I am not sure I understand the derivation of the square of the > amplitude, but I will (re)read this more at ease when I have more time, and > let you know. > > Hmm... What do you mean by uniform measure on infinite set? > > >> The only place a derivative appears is at D.13. IIUC, derivatives are >> well defined operators for any sort of timescale, not just continuous >> ones. In discrete timescales, the derivative is just a difference >> operator IIRC. >> > > OK, but why a derivative? Why the reals ? > > > > >> Effectivity? >> > > > You require that phi(t') follows deterministically from phi(t) when t' < > t. (page 221). > Lewontin's requirement is a bit like forcing the measure, which is not > obvious a priori in the digital perspective. > It might works, but needs deeper justifications. > > > > > > >> >>> What is really missing, but for good reason, is the fact that even >>> if correct, all the assumptions (sometimes implicit or argued too >>> much quickly) must be re-extracted from self-reference, once we >>> assume computationalism, so as to be able to benefit from the >>> Gödel-Solovay split of the points of view. This is needed for the >>> mind-body problem. >>> >>> >> That is a fair comment, though not one I have a ready answer for :). >> > > OK :) > > > > >> We can come back on this later. You might search on Lucien Hardy, as >>> it gave a similar derivation, assuming perhaps less probability >>> axioms than Russell. >>> >> >> I don't believe Hardy's derivation is at all similar to mine. >> > > I agree. I cannot right now put my hand on it (unlike your book) Is this the same? http://arxiv.org/abs/quant-ph/0101012 Jason > > > > I >> actually found his postulates rather hard to accept on first >> principles. >> >> The approach that seems most similar to mine is Gunther Ludwig's >> (Grundlagen der Quantum Mechanik), but that is a seriously formal >> approach that is hard to penetrate. >> > > > Normally I have an english translation, or it is in a box hardly > accessible. > Or I confuse it with another book. > > > > >> I read that a long time ago, so I am not sure. >>> I should reread Russel's one too. I am no more sure if the >>> explantion of the square amplitude is equivalent with Everett, or >>> Finkelstein one. >>> >>> >> It would be nice to know :). >> > > I don't think it is the same. I refer to the "usual" idea of defining a > frequency operator, and showing its eigenvalues gives the Born rules in the > limit. It is the basic idea of Graham in DeWitt's book. I am not entirely > convinced by this either, but I do think that Gleason theorem do solve that > problem. (but from the SWE of course, not from comp, nor in the spirit of > your approach). > > Bruno > > > > > >> >> -- >> >> >> >> Prof Russell Standish Phone 0425 253119 (mobile) >> Principal, High Performance Coders >> Visiting Professor of Mathematics hpco...@hpcoders.com.au >> University of New South Wales http://www.hpcoders.com.au >> >> Latest project: The Amoeba's Secret >> (http://www.hpcoders.com.au/AmoebasSecret.html) >> >> >> >> -- >> 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. >> > > http://iridia.ulb.ac.be/~marchal/ > > > > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving
Quantum Computers
There is a important paper in today's journal Nature on error correction that would be needed to make Quantum Computers practical. Although they still can't protect individual Qubits they could protect the entanglement of 3 or more particles (the Greenberger–Horne–Zeilinger state) and they could use quantum methods to correct errors in classical information. You can read the entire Nature article here: http://www.nature.com/articles/nature14270.epdf?referrer_access_token=5eOcIrxJit57oQ9AbgUbcNRgN0jAjWel9jnR3ZoTv0Nl3_SWJL2Yj5LBgXNo8IyXld_hUdCO7LMnjkzAUvEu1ETPBAMDGRQAzb51sv1KX3628izQUsDesAmmBuYpNfD3zJeEJgdakb-4n-9r6NfFMDcXMb7brdrg8GdxwCaK0AOtkOpERCNsLwWYs-_5SqvkD9LCpvhDijqiyzBWHOBtp9ZYlXdPGD3zqb5YUFaPXTlLU2-2-0C_A7cpb1g9xJzt&tracking_referrer=www.nytimes.com You can also read a article about it in today's New York Times here: http://www.nytimes.com/2015/03/05/science/quantum-computing-nature-google-uc-santa-barbara.html?_r=0 John K Clark -- 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: Why is there something rather than nothing? From quantum theory to dialectics?
On 3/5/2015 10:21 AM, Bruno Marchal wrote: On 04 Mar 2015, at 23:05, meekerdb wrote: On 3/4/2015 10:43 AM, Bruno Marchal wrote: On 13 Feb 2015, at 20:40, Samiya Illias wrote: My faith encourages me to pursue the sciences, to use my faculties and intelligence for reason and logic, and the study of the sciences is not doubt. Doubt is the lack of faith! I am not sure I commented on this. It might be the heart of the matter. Science is only doubt. But as Descartes saw, we cannot doubt of everything, and so, we do trust something. The more we are able to doubt, the more we can see what remains undoubtable, and faith can build on that. So, those who have the faith have no problem doubting any theories, texts, etc. The faith rises from within, and is definitely beyond words, texts, theories, equations, etc. The universal machines are confronted to something similar when they introspect themselves (in the sense of Kleene second recursion diagonal way). In front of the absolute truth, science can only augment the doubt, but without ever needing to abandon faith. It is the faith in the ineffable which invites the doubt on *all* the fables. So you must have faith - but not in anything in particular? Why? I didn't say that. Of course you didn't. It's ineffable. :-) I can see why a logician would think that way; since he always wants to start from axioms he assumes. Not at all. Humans start from a reality and develop beliefs on that reality, and they assume axioms to have their theories, but they doubt the theory, as they trust the reality. Fundamental reality kicks back all theories, but that is nice, as it is a promise of infinite learning and surprises. But note the Google paper on "Knowledge Based Trust" which tries to operationalize the coherence theory of truth. Not too bad blaspheme for the practical purpose, although it can't really work, but that is another topic. Fundamentally you should not like it, as it confuse truth and reality (possibility/consistency). It confuses p and <>p. It confuses "p is true" with there is a reality in which p is true. Does "p is true" mean p is true in *this* reality, or what? Brent -- 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: Philip Ball, MWI skeptic
On 3/5/2015 9:22 AM, Bruno Marchal wrote: But that would entail: provable(false) -> false, which is equivalent with: not-provable(false). But that is consistency, and is not provable. So in general, due to the second theorem of incompleteness, we don't have in general that: provable(p) -> p. I'm not sure what "in general we don't" means here. Do you mean: For every p, it is false that provable(p) -> p? Or do you mean: For some p, it is false that provable(p) -> p? But Ep~([]p->p) is equivalent to Ep([]p&~p), which asserts inconsistency. You don't want to assert inconsistency, only the possibility of inconsistency. Brent -- 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: Philip Ball, MWI skeptic
On 05 Mar 2015, at 06:12, Russell Standish wrote: On Wed, Mar 04, 2015 at 06:06:35PM +0100, Bruno Marchal wrote: My opinion has not much changed since the last critics. It is a very nice derivation, but too much quick at some step, assuming the reals, derivative, effectivity, etc. It go in the right conceptual direction, (from the comp perspective). The reals come with Kolmogorov's axioms. They also appear as part of measure theory. Perhaps it can be done without invoking the reals, perhaps not. Plausibly. On any rich enough topological group I presume. Why information must be preserved between observer moments? You are quick in making the observer moments into a complex vector space (your refer to 4.5, in your appendix, but you are quick in 4.5). It is interesting, but if you make things formal, there are still many assumptions, including the existence of the measure. It might help in the comp derivation of physics. Just now, I am not sure I understand the derivation of the square of the amplitude, but I will (re)read this more at ease when I have more time, and let you know. Hmm... What do you mean by uniform measure on infinite set? The only place a derivative appears is at D.13. IIUC, derivatives are well defined operators for any sort of timescale, not just continuous ones. In discrete timescales, the derivative is just a difference operator IIRC. OK, but why a derivative? Why the reals ? Effectivity? You require that phi(t') follows deterministically from phi(t) when t' < t. (page 221). Lewontin's requirement is a bit like forcing the measure, which is not obvious a priori in the digital perspective. It might works, but needs deeper justifications. What is really missing, but for good reason, is the fact that even if correct, all the assumptions (sometimes implicit or argued too much quickly) must be re-extracted from self-reference, once we assume computationalism, so as to be able to benefit from the Gödel-Solovay split of the points of view. This is needed for the mind-body problem. That is a fair comment, though not one I have a ready answer for :). OK :) We can come back on this later. You might search on Lucien Hardy, as it gave a similar derivation, assuming perhaps less probability axioms than Russell. I don't believe Hardy's derivation is at all similar to mine. I agree. I cannot right now put my hand on it (unlike your book) I actually found his postulates rather hard to accept on first principles. The approach that seems most similar to mine is Gunther Ludwig's (Grundlagen der Quantum Mechanik), but that is a seriously formal approach that is hard to penetrate. Normally I have an english translation, or it is in a box hardly accessible. Or I confuse it with another book. I read that a long time ago, so I am not sure. I should reread Russel's one too. I am no more sure if the explantion of the square amplitude is equivalent with Everett, or Finkelstein one. It would be nice to know :). I don't think it is the same. I refer to the "usual" idea of defining a frequency operator, and showing its eigenvalues gives the Born rules in the limit. It is the basic idea of Graham in DeWitt's book. I am not entirely convinced by this either, but I do think that Gleason theorem do solve that problem. (but from the SWE of course, not from comp, nor in the spirit of your approach). Bruno -- Prof Russell Standish Phone 0425 253119 (mobile) Principal, High Performance Coders Visiting Professor of Mathematics hpco...@hpcoders.com.au University of New South Wales http://www.hpcoders.com.au Latest project: The Amoeba's Secret (http://www.hpcoders.com.au/AmoebasSecret.html) -- 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. http://iridia.ulb.ac.be/~marchal/ -- 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: Philip Ball, MWI skeptic
On 3/5/2015 7:14 AM, Bruno Marchal wrote: On 04 Mar 2015, at 21:32, meekerdb wrote: On 3/4/2015 7:51 AM, Bruno Marchal wrote: If we are in a simulated world, we are in all simulated world, some normal, or some "perverse bostromian" (made by our normal descendents who would like to fake our reality). We can test computationalism V perverse bostromism, if you want. Why should that be true. We weren't in this simulated world for the fire 13.8e9yrs. Are you saying it's impossible to create/simulate a world without Bruno Marchal in it? Yes. It follows from our having infinity of virtual bodies in arithmetic. ?? How does it follow? If you simulate Bruno Marchal + "the real world/physical laws": you will fail to entangle his first person experience with yours (outside the simulation). So what? The simulated Bruno need only be entangled with things in the simulated world. But the question was not whether you could simulate Bruno Marchal without entangling him in the outside (real?) world. The question was whether you could create a simulated world that did not contain Bruno Marchal. If it's possible to simulate a world at all, it should be possible to simulate this world as it existed a billion years ago or a 100yrs ago - when there was no Bruno Marchal. Brent From its perspective he is as much in the simulated world than it is not. If you simulate Bruno Marchal + "some fake world": Bruno Marchal will soon or later be able to discover it, at least IF Bruno Marchal bet on computationalism. Of course, if each time Bruno Marchal see that it belongs in a simulation, you can correct it or change his mind. But you will need to do that infinitely often, or make BM into someone mad, or something like that. (But then you are no more simulating him). In that case, doing that infinite work, you can fail him. To test if we are in a simulation, assuming comp, it is necessary and sufficient to compare the physics extracted from comp, with the physics allowed by observation. Bruno -- 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: Why is there something rather than nothing? From quantum theory to dialectics?
On 04 Mar 2015, at 23:05, meekerdb wrote: On 3/4/2015 10:43 AM, Bruno Marchal wrote: On 13 Feb 2015, at 20:40, Samiya Illias wrote: My faith encourages me to pursue the sciences, to use my faculties and intelligence for reason and logic, and the study of the sciences is not doubt. Doubt is the lack of faith! I am not sure I commented on this. It might be the heart of the matter. Science is only doubt. But as Descartes saw, we cannot doubt of everything, and so, we do trust something. The more we are able to doubt, the more we can see what remains undoubtable, and faith can build on that. So, those who have the faith have no problem doubting any theories, texts, etc. The faith rises from within, and is definitely beyond words, texts, theories, equations, etc. The universal machines are confronted to something similar when they introspect themselves (in the sense of Kleene second recursion diagonal way). In front of the absolute truth, science can only augment the doubt, but without ever needing to abandon faith. It is the faith in the ineffable which invites the doubt on *all* the fables. So you must have faith - but not in anything in particular? Why? I didn't say that. I can see why a logician would think that way; since he always wants to start from axioms he assumes. Not at all. Humans start from a reality and develop beliefs on that reality, and they assume axioms to have their theories, but they doubt the theory, as they trust the reality. Fundamental reality kicks back all theories, but that is nice, as it is a promise of infinite learning and surprises. But note the Google paper on "Knowledge Based Trust" which tries to operationalize the coherence theory of truth. Not too bad blaspheme for the practical purpose, although it can't really work, but that is another topic. Fundamentally you should not like it, as it confuse truth and reality (possibility/consistency). It confuses p and <>p. It confuses "p is true" with there is a reality in which p is true. Bruno Brent -- 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. http://iridia.ulb.ac.be/~marchal/ -- 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: Philip Ball, MWI skeptic
On 04 Mar 2015, at 23:02, meekerdb wrote: On 3/4/2015 10:21 AM, Bruno Marchal wrote: The SWE contains observables (operators) such as position, energy and momentum and so on. What bases do we choose for these operators? The default, that no one ever questions (to the extent that I doubt that many people realize that it is an arbitrary choice) is that the eigenvalues of the position operator are values along the real line and the eigenfunctions are delta functions of reals. In any other basis, position eigenvalues would be superpositions of these reals, and the eigenfunctions would be quite different. Why do we unquestioningly accept the basis commonly used? Because it is the base selected by millions years of life evolution. Basically we must select between Good and Bad, for this we need a distinguishability ability. Orthogonal position might have been preferred for contingent reason or for more deep theoretical reason. It is just that once you have a body, "nature" has chosen a base for you. The answer, of course, is that we choose the basis such that we can bring our classical experience and intuitions to bear --which is essentially the same as Bohr's notion of the 'Correspondence Principle' -- QM has to reproduce the results of classical physics in the appropriate limit. OK. Once one realizes this, one can see that QM, and the SWE in particular, presupposes a classical world -- Only a classical mind. One reason may be that the primary interactions important for life are more position than momentum dependent. A tiger can only eat you if you and the tiger are near each other. If there were beings that lived in orbit then perhaps they would have evolved to directly perceive orbital parameters instead of position. For signals, we can always do a Fourier transformation, which is a change of complementary base. The choice of base is imposed by the existence of some machine ability to distinguish two states, so that it can reason and act classically, which is the base of the possible thought compression of data, and the consciousness/consistency sped-up. Bruno Brent -- 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. http://iridia.ulb.ac.be/~marchal/ -- 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: Philip Ball, MWI skeptic
On 04 Mar 2015, at 22:53, meekerdb wrote: On 3/4/2015 10:00 AM, Bruno Marchal wrote: It seems that this kind of information theoretic question might be one that mind-as-computation could address: Why is it we can only think of the world in these limited, classical ways (if indeed that's the case)? For example we do all our scattering calculations in momentum-space; might there be sentient beings that conceptualize in momentum space instead of position space? Maybe dolphins and bats do it since they are more audio dependent. Interesting question, but the computationalist measure problem depends only on our sigma_1 completeness. Now, it is typical to assume some rather high level of substitution, and benefit from some classical assumptions, like the classical laws of thought (Boolean logic). RA, PA are classical theory. We assume classical logic, and we use it (implicitely or explicitly) in number theory and computer science. So, yes, that is a common between Bohr, Everett and classical computationalism: mind works classically. But note that the UDA does not assumes this, the argument works even if the mind exploits quantum computations (which I doubt, except for that global selection imposed by the sum on all computations below the substitution). It's *because* it doesn't assume classicality of mind that it might be able to predict it. May be. Strictly speaking we don't know. We do have evidence that classical or intuitionistic logic makes more sense intuitively than quantum logic. We don't think quantum logically. We don't use quantum logic when writting books on Hilbert sapce and quantum logic. Quantum logic is a logic of doing experience/experiment, and linking measurable numbers. Bruno Brent -- 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. http://iridia.ulb.ac.be/~marchal/ -- 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: Philip Ball, MWI skeptic
On 04 Mar 2015, at 22:13, LizR wrote: On 5 March 2015 at 09:32, meekerdb wrote: On 3/4/2015 7:51 AM, Bruno Marchal wrote: If we are in a simulated world, we are in all simulated world, some normal, or some "perverse bostromian" (made by our normal descendents who would like to fake our reality). We can test computationalism V perverse bostromism, if you want. Why should that be true. We weren't in this simulated world for the fire 13.8e9yrs. Are you saying it's impossible to create/simulate a world without Bruno Marchal in it? Sorry I don't follow. What is perverse bostromism? (I know who Bostrom is and his ideas on us being in a 13th floor situation...is the perverse version like Descartes' demon?) Good point. It can probably be related to Descartes demon. Good subject of research. What I say here is what I explained to Brett Hall a long time ago, probably on the FOR list. You must keep in mind the global FPI all the time (like in step seven). By "bostromism" I mean the idea that our descendent, or our contemporaries, emulate ourself in some (physically realized) computer. In that case, either they simulate the correct physical laws (if that is possible), but then, from our first person view we are both in and outside the emulation, and don't see any difference between the observed physics and the comp physics (qZ1*, say). Or they simulate incorrect physical laws, like in a virtual video game, with more precision. In that case we will observe the difference. And why is Bruno suggesting it's impossible ot simulate a world without him in? See my answer to brent. Eventually this is related to the fact that we can never be sure to be "not dreaming", but we can know, from times to times, that we are dreaming. (Clearly he knows worlds without him can be simulated - we can simulate the weather, with nobody in that simulated world to experience the virtual rain, in order to make forecasts, for example!) Sure, all those emulation exists in the arithmetical reality, we cannot avoid them. But our physics must be a sum on all computations (by the global FPI, by the first person unawareness of the UD steps) , and so it is not obvious if physics is Turing emulable. But physics must be Turing universal, because *we* are Turing universal, and we even bet we are not more than that when saying yes to the doctor. That is in a relative sense, where the most probable oracle (environment) is itself locally computable (enough to emulate universal machine, like brains and computers). Bruno -- 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. http://iridia.ulb.ac.be/~marchal/ -- 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: Philip Ball, MWI skeptic
On 04 Mar 2015, at 21:36, LizR wrote: On 5 March 2015 at 04:37, Bruno Marchal wrote: So it is not the state of the halting problem which are physical, it is the physical which needs to be redefined in term of a measure (or the logic of the measure one, of that measure) on the halting programs. Yes, that's what I was trying to say, in my roundabout way. Using "physical" confuses the matter, if you'll pardon the pun. There is no reversal in Tegmark. He misses the mind-body problem in general, and the computationalist one in particular. Yes, he is in the interesting position of being what might be called a "mathematical materialist" - deriving the material world from maths and finding he still has the mind-body problem, which he then solves by saying it isn't a problem (as for example Dennett does. Of course he may be right...) He may be right? Well, even if right, he has to prove it, and by definition, that is the mind-body problem! There is just no choice in the matter, computationalism implies the necessity of recovering the physical laws from digital machine's self-reference. That is verified up to now, in the special frame of the classical theory of knowledge. I wish I understood the argument well enough to either agree or disagree. It seems (to me) to be sound up to the MGA, modulo (as it were) Brent's comments about maths. If you get UDA 1-7, you get it all, unless you think that ultrafinitism is reasonable, or that Occam razor (the usual one) is not reasonable. I am not sure which comments by Brent about the math you allude too. If you could elaborate a little bit ... I find it just about equally difficult to take the leap EITHER to your view that the physical world is what falls out of abstract computations The point is that you should not make any such leap. It follows from computationalism. To escape this, you need a magic matter + a magic ability by some universal Turing machine to detect it. OR to Brent's view that maths is something we invented that just happens to be unreasonably effective at describing a (so-far inexplicable, merely brute-fact) reality. That is the fulcrum of my agnosticism, as it were. Einstein himself took his entire life to understand that math kicks back. It is common with physicists. (To sum up statements from Pale Yourgreau's book on Einstein and Gödel). Incompleteness provides the nuances needed for distinguishing truth, believable, knowable, observable, and the sensible, and what is sharable, and what is not sharable. I can believe that, even though I probably wouldn't find it easy to follow the logical steps of the argument. But that parts needs the study of some amount of classical mathematical logic. I use quite standard notions. Usually, layman (and all mathematician before Gödel) we think that: provable(p) -> p, for any proposition p. But that would entail: provable(false) -> false, which is equivalent with: not-provable(false). But that is consistency, and is not provable. So in general, due to the second theorem of incompleteness, we don't have in general that: provable(p) -> p. This means also that provable(p) and "provable(p) & p" will obey to different logic. Let us define Believe(p) = provable(p) This makes sense as we limit ourself to correct machine, for which God knows that provable(p) -> p, but the machine itself does not necessarily knows that. We can define a notion of knowledge attached to the machine by identifying knowable(p) by believable(p) & p, à-la Theaetetus. Obviously, by simple propositional calculus: knowable(p) -> p (given that (believable(p) & p) -> p, given that "(q & p) -> p" is a tautology. so knowable and believable are different. And the machine can't miss this, as they can prove their own Gödel's theorem. Then the machine says more: the logic of knowable obeys to the logic S4Grz. The point here is that incompleteness ~[]f -> ~[](~[]f) forces the knowable (which has to obey to S4) to differ from the believable, even if we know that the predicate are co-extensive (the same arithmetical p are known and believed). But they obey different logic. Believable obeys G, and knowable obeys S4Grz, and the culprit for this is incompleteness. The same occurs for all other intensional nuances: []p & <>t, []p & <>t & p, ... That []p & p is a way to define knowledge is known since Theaetetus (It is a definition which manages well the dream argument, as I explain with all details in "conscience & mécanisme). What you might ask is why to define observable (with measure one) by []p & <>t ?, and this with the interpretation or p limited to the sigma_1 arithmetical sentence. Well, take the simple projective (yes-no measurement) observable "coffee?", in the WM duplication experience, with a protocol where you are told in advance (in Helsinki) that you will receive a cup o
Re: Philip Ball, MWI skeptic
On 04 Mar 2015, at 21:32, meekerdb wrote: On 3/4/2015 7:51 AM, Bruno Marchal wrote: If we are in a simulated world, we are in all simulated world, some normal, or some "perverse bostromian" (made by our normal descendents who would like to fake our reality). We can test computationalism V perverse bostromism, if you want. Why should that be true. We weren't in this simulated world for the fire 13.8e9yrs. Are you saying it's impossible to create/simulate a world without Bruno Marchal in it? Yes. It follows from our having infinity of virtual bodies in arithmetic. If you simulate Bruno Marchal + "the real world/physical laws": you will fail to entangle his first person experience with yours (outside the simulation). From its perspective he is as much in the simulated world than it is not. If you simulate Bruno Marchal + "some fake world": Bruno Marchal will soon or later be able to discover it, at least IF Bruno Marchal bet on computationalism. Of course, if each time Bruno Marchal see that it belongs in a simulation, you can correct it or change his mind. But you will need to do that infinitely often, or make BM into someone mad, or something like that. (But then you are no more simulating him). In that case, doing that infinite work, you can fail him. To test if we are in a simulation, assuming comp, it is necessary and sufficient to compare the physics extracted from comp, with the physics allowed by observation. Bruno Brent -- 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. http://iridia.ulb.ac.be/~marchal/ -- 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.
