Re: What are wavefunctions?
On 05 Feb 2014, at 02:45, Russell Standish wrote: On Tue, Feb 04, 2014 at 08:49:57PM +1300, LizR wrote: I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the *multiverse* is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) Rather less, I would expect, for the reasons outlined in Theory of Nothing... Yes rather less. It is the basic idea that taking everything is conceptually more simple than choosing anything among the everything. It is the main motivation for this list. Well, easier conceptually, but technically, this is only true up to be able to justify the white rabbits away, of course. I understand nothing only at that conceptual meta-level of 0-information theory, although it is more few- bits-information theory. 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 -- 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. 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/groups/opt_out.
Re: What are wavefunctions?
On 04 Feb 2014, at 07:16, meekerdb wrote: On 2/3/2014 10:00 PM, Russell Standish wrote: On Tue, Jan 07, 2014 at 12:44:57PM -0800, meekerdb wrote: Layzer of course didn't know about the holographic principle, which implies that the maximum possible entropy increases in proportion to the surface area of the Hubble sphere rather than the volume. Vic Stenger has noted that if you assume the degrees of freedom for the vacuum are proportional to this area (in Planck units) you get the right order of magnitude for the energy density of the cosmological constant. Wow! That's quite something. Did Vic ever write this up somewhere? Cheers It's in section 12.2 of his 2011 book The Fallacy of Fine Tuning. I appreciate that book, and basically everything Vic Stenger wrote on physics. I am less enthusiast when he talk on God, despite I still agree with everything he says. I don't believe in the God he is criticizing, nor on the need to advertise it in that way. 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/groups/opt_out. 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/groups/opt_out.
Re: What are wavefunctions?
On 2/3/2014 11:49 PM, LizR wrote: I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the /multiverse/ is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) But presumably only because it can have much bigger Hubble spheres. For a given size Hubble sphere, which is to say for a given epoch after the big bang, there are only finitely many different possible Hubble spheres. At least that's the theory. 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/groups/opt_out.
Re: What are wavefunctions?
On 5 February 2014 06:24, meekerdb meeke...@verizon.net wrote: On 2/3/2014 11:49 PM, LizR wrote: I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the *multiverse* is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) But presumably only because it can have much bigger Hubble spheres. For a given size Hubble sphere, which is to say for a given epoch after the big bang, there are only finitely many different possible Hubble spheres. Yes, I was only thinking of the subsection of the multiverse that includes Hubble spheres of equal size to ours. Also I was only thinking of the quantum multiverse, not the various alternatives. Given those constraints, I wonder if the information content would come out proportional to the volume? I guess if we assume space-time is quantised, then we can get a maximum number of bits (maybe one per Planck volume?) - I suppose the multiverse would then be every possible value that can occupy those volumes. So say 2^N, where N=number of Planck volumes, which is around 10^180 according to a quick calculation, and assuming I haven't slipped up, perish the thought. That doesn't seem right, though, because the Hubble sphere isn't occupied anything like randomly, and presumably most multiverse branches aren't either. I wonder how one could cut down the number? Or if one should? Any further thoughts on this? -- 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: What are wavefunctions?
On Tue, Feb 04, 2014 at 08:49:57PM +1300, LizR wrote: I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the *multiverse* is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) Rather less, I would expect, for the reasons outlined in Theory of Nothing... -- 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 -- 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: What are wavefunctions?
On 5 February 2014 14:45, Russell Standish li...@hpcoders.com.au wrote: On Tue, Feb 04, 2014 at 08:49:57PM +1300, LizR wrote: I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the *multiverse* is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) Rather less, I would expect, for the reasons outlined in Theory of Nothing... Good point. In fact it presumably contains just enough information to represent the laws of physics. However, although the information sums to almost nothing, could there be some relation between the holographic principle and the multiverse, possibly information-related, as suggested? -- 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: What are wavefunctions?
On Wednesday, February 5, 2014 1:45:18 AM UTC, Russell Standish wrote: On Tue, Feb 04, 2014 at 08:49:57PM +1300, LizR wrote: I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the *multiverse* is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) Rather less, I would expect, for the reasons outlined in Theory of Nothing... Is there a summary of ToN anywhere? -- Prof Russell Standish Phone 0425 253119 (mobile) Principal, High Performance Coders Visiting Professor of Mathematics hpc...@hpcoders.com.aujavascript: University of New South Wales http://www.hpcoders.com.au -- 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: What are wavefunctions?
I don't know about a summary, but the whole book is available here: http://www.hpcoders.com.au/theory-of-nothing.pdf On 5 February 2014 17:58, ghib...@gmail.com wrote: On Wednesday, February 5, 2014 1:45:18 AM UTC, Russell Standish wrote: On Tue, Feb 04, 2014 at 08:49:57PM +1300, LizR wrote: I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the *multiverse* is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) Rather less, I would expect, for the reasons outlined in Theory of Nothing... Is there a summary of ToN anywhere? -- 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: What are wavefunctions?
On Wed, Feb 05, 2014 at 06:42:14PM +1300, LizR wrote: I don't know about a summary, but the whole book is available here: http://www.hpcoders.com.au/theory-of-nothing.pdf Thanks Liz. I should also add that I was alluding to the zero information principle (Tegmark may call this the minimal information principle, IIRC), which is really the subject of chapters 2 3 of my book. Cheers On 5 February 2014 17:58, ghib...@gmail.com wrote: On Wednesday, February 5, 2014 1:45:18 AM UTC, Russell Standish wrote: On Tue, Feb 04, 2014 at 08:49:57PM +1300, LizR wrote: I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the *multiverse* is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) Rather less, I would expect, for the reasons outlined in Theory of Nothing... Is there a summary of ToN anywhere? -- 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. -- 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 -- 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: What are wavefunctions?
On Tue, Jan 07, 2014 at 12:44:57PM -0800, meekerdb wrote: Layzer of course didn't know about the holographic principle, which implies that the maximum possible entropy increases in proportion to the surface area of the Hubble sphere rather than the volume. Vic Stenger has noted that if you assume the degrees of freedom for the vacuum are proportional to this area (in Planck units) you get the right order of magnitude for the energy density of the cosmological constant. Wow! That's quite something. Did Vic ever write this up somewhere? Cheers -- 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 -- 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: What are wavefunctions?
On 2/3/2014 10:00 PM, Russell Standish wrote: On Tue, Jan 07, 2014 at 12:44:57PM -0800, meekerdb wrote: Layzer of course didn't know about the holographic principle, which implies that the maximum possible entropy increases in proportion to the surface area of the Hubble sphere rather than the volume. Vic Stenger has noted that if you assume the degrees of freedom for the vacuum are proportional to this area (in Planck units) you get the right order of magnitude for the energy density of the cosmological constant. Wow! That's quite something. Did Vic ever write this up somewhere? Cheers It's in section 12.2 of his 2011 book The Fallacy of Fine Tuning. 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/groups/opt_out.
Re: What are wavefunctions?
On Mon, Feb 03, 2014 at 10:16:15PM -0800, meekerdb wrote: On 2/3/2014 10:00 PM, Russell Standish wrote: On Tue, Jan 07, 2014 at 12:44:57PM -0800, meekerdb wrote: Layzer of course didn't know about the holographic principle, which implies that the maximum possible entropy increases in proportion to the surface area of the Hubble sphere rather than the volume. Vic Stenger has noted that if you assume the degrees of freedom for the vacuum are proportional to this area (in Planck units) you get the right order of magnitude for the energy density of the cosmological constant. Wow! That's quite something. Did Vic ever write this up somewhere? Cheers It's in section 12.2 of his 2011 book The Fallacy of Fine Tuning. Brent Not in a peer reviewed article, then. Mind you I don't blame him, given the current state of peer review. I'm unfortunately not sufficiently interested to buy the book, nor is it available in my uni's library :(. I'll have to leave this on my toread list. Cheers -- 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 -- 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: What are wavefunctions?
On 2/3/2014 11:14 PM, Russell Standish wrote: On Mon, Feb 03, 2014 at 10:16:15PM -0800, meekerdb wrote: On 2/3/2014 10:00 PM, Russell Standish wrote: On Tue, Jan 07, 2014 at 12:44:57PM -0800, meekerdb wrote: Layzer of course didn't know about the holographic principle, which implies that the maximum possible entropy increases in proportion to the surface area of the Hubble sphere rather than the volume. Vic Stenger has noted that if you assume the degrees of freedom for the vacuum are proportional to this area (in Planck units) you get the right order of magnitude for the energy density of the cosmological constant. Wow! That's quite something. Did Vic ever write this up somewhere? Cheers It's in section 12.2 of his 2011 book The Fallacy of Fine Tuning. Brent Not in a peer reviewed article, then. Mind you I don't blame him, given the current state of peer review. I'm unfortunately not sufficiently interested to buy the book, nor is it available in my uni's library :(. I'll have to leave this on my toread list. He also mentions it here http://www.colorado.edu/philosophy/vstenger/BookChapters/OxNoEv13.pdf on pg 53, but without a calculation (which is very short anyway). Brent Cheers -- 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: What are wavefunctions?
I did wonder once if, since the holographic principle implies that the information in a universe is proportional to the surface area of the Hubble sphere, could it be that the information in the *multiverse* is proportional to the volume of the Hubble sphere? (Although I guess the multiverse probably contains way more info than that...) -- 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: What are wavefunctions?
On 16 Jan 2014, at 18:53, meekerdb wrote: On 1/15/2014 11:42 PM, Jason Resch wrote: On Thu, Jan 16, 2014 at 12:58 AM, meekerdb meeke...@verizon.net wrote: On 1/15/2014 7:05 PM, Jason Resch wrote: Hyper determinism makes little sense as a serious theory to me. Why should particle properties conform to what a computer's random number generator outputs, and then the digits of Pi, and then the binary expansion of the square root of 2, all variously as the experimenters change the knobs as to what determines the spin axis of the lepton their analyzer measures. Are radioactive decays of particles really such things that are governed by the behavior of a selected random source, or alternately, are they really such things that govern what the digits of Pi or the square root of 2 are? They are all part of the same reality. Are they? Aren't numbers like Pi and sqrt(2) beyond the reality of QM, or rather, more fundamental than it? The moment you admit numbers like Pi into your reality, you get much more than just QM. Of course QM is just a model A theory. of how we think the world works...like arithmetic is a model of countable things. Neither one is *reality*. PA is a reality, by itself, indeed an existing Löbian machine, and PA talks about a reality which is vaster than PA, and that no machine can grasp in its entirety. You confuse theory and model here. You assume its the experimental choice of measurement that determines the particles response, but I think the picture is supposed to be that both the particle in the experiment and the particles making up the experimenter are determined by the same laws. So how, when using the digits of Pi to decide whether to measure the x-axis, or the y-axis, does the particle (when it decays), know to have both electron and positron agree measured on some axis, when that axis is determined by some relation between a circle and its diameter? Here the laws involved seemed to go beyond physical laws, it introduces mathematical laws, which can selectively be made to control/guide physics.. They only 'seem to' because you neglect the fact that in the experiment you don't use the digits of pi from Platonia, you use their physical instantiation as calculated in the registers of a computer or written ink on a page. You agree that there is a difference between Platonia, and the inside more terrestrial perception of it. 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/groups/opt_out. 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/groups/opt_out.
Re: What are wavefunctions?
On 16 Jan 2014, at 22:31, LizR wrote: Everything else I've said on this subject has been in response to people trying to argue that physics is not time symmetric. So far all such arguments have been a variant on the second law says so and my response has been a variant on the second law emerges above the level at which we can detect time symmetry. (Plus I've invoked boundary conditions on the universe to explain how the second law can arise from time symmetric physics...) I agree a priori with you on this. I can agree also that this time-symmetry (of QM, which time symmetrical) + boundary special condition can be consistent with QM + one reality (although weird and not satisfying) I think pure QM (without boundary condition, that is MW) is even more symmetrical, and conceptually more simple, and that your point go through it. The boundary condition a still a way to select a dream as more real than other dream, and of course, does or make sense in comp, unless the numbers conspire in making the whole geography into physics which is not reasonable. Bruno 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/groups/opt_out.
Re: What are wavefunctions?
On 1/17/2014 2:18 AM, Bruno Marchal wrote: PA is a reality, by itself, indeed an existing Löbian machine, and PA talks about a reality which is vaster than PA, and that no machine can grasp in its entirety. You confuse theory and model here. You can't kick Peano's axioms. 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/groups/opt_out.
Re: What are wavefunctions?
On Jan 17, 2014, at 6:58 PM, meekerdb meeke...@verizon.net wrote: On 1/17/2014 2:18 AM, Bruno Marchal wrote: PA is a reality, by itself, indeed an existing Löbian machine, and PA talks about a reality which is vaster than PA, and that no mac hine can grasp in its entirety. You confuse theory and model here. You can't kick Peano's axioms. What is your point? That things don't exist unless you can kick them? Jason 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/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: What are wavefunctions?
On 18 January 2014 16:08, Jason Resch jasonre...@gmail.com wrote: On Jan 17, 2014, at 6:58 PM, meekerdb meeke...@verizon.net wrote: On 1/17/2014 2:18 AM, Bruno Marchal wrote: PA is a reality, by itself, indeed an existing Löbian machine, and PA talks about a reality which is vaster than PA, and that no machine can grasp in its entirety. You confuse theory and model here. You can't kick Peano's axioms. What is your point? That things don't exist unless you can kick them? Real things kick back. Maths kicks back... -- 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: What are wavefunctions?
On 1/17/2014 7:34 PM, LizR wrote: On 18 January 2014 16:08, Jason Resch jasonre...@gmail.com mailto:jasonre...@gmail.com wrote: On Jan 17, 2014, at 6:58 PM, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/17/2014 2:18 AM, Bruno Marchal wrote: PA is a reality, by itself, indeed an existing Löbian machine, and PA talks about a reality which is vaster than PA, and that no machine can grasp in its entirety. You confuse theory and model here. You can't kick Peano's axioms. What is your point? That things don't exist unless you can kick them? Real things kick back. Maths kicks back... Only metaphorically. 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/groups/opt_out.
Re: What are wavefunctions?
On 18 January 2014 18:50, meekerdb meeke...@verizon.net wrote: On 1/17/2014 7:34 PM, LizR wrote: On 18 January 2014 16:08, Jason Resch jasonre...@gmail.com wrote: On Jan 17, 2014, at 6:58 PM, meekerdb meeke...@verizon.net wrote: On 1/17/2014 2:18 AM, Bruno Marchal wrote: PA is a reality, by itself, indeed an existing Löbian machine, and PA talks about a reality which is vaster than PA, and that no machine can grasp in its entirety. You confuse theory and model here. You can't kick Peano's axioms. What is your point? That things don't exist unless you can kick them? Real things kick back. Maths kicks back... Only metaphorically. Fairly obviously. (I refute it thus! said Samuel Johnson, stubbing his toe against the irrationality of pi.) -- 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: What are wavefunctions?
On Fri, Jan 17, 2014 at 11:50 PM, meekerdb meeke...@verizon.net wrote: On 1/17/2014 7:34 PM, LizR wrote: On 18 January 2014 16:08, Jason Resch jasonre...@gmail.com wrote: On Jan 17, 2014, at 6:58 PM, meekerdb meeke...@verizon.net wrote: On 1/17/2014 2:18 AM, Bruno Marchal wrote: PA is a reality, by itself, indeed an existing Löbian machine, and PA talks about a reality which is vaster than PA, and that no machine can grasp in its entirety. You confuse theory and model here. You can't kick Peano's axioms. What is your point? That things don't exist unless you can kick them? Real things kick back. Maths kicks back... Only metaphorically. The laws of physics prevent you from traveling at a speed more than ~300,000,000 m/s. The laws of arithmetic prevent you from writing down more than 2 distinct factors of 17. They seem equally forceful, each in their own way. The laws of mathematics may be even more forceful, for it is conceivable in some physical universe you can go faster than the speed of light in this universe, it is much harder to conceive of a universe where you could write down a third factor of 17. Jason -- 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: What are wavefunctions?
On 1/17/2014 10:16 PM, Jason Resch wrote: On Fri, Jan 17, 2014 at 11:50 PM, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/17/2014 7:34 PM, LizR wrote: On 18 January 2014 16:08, Jason Resch jasonre...@gmail.com mailto:jasonre...@gmail.com wrote: On Jan 17, 2014, at 6:58 PM, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/17/2014 2:18 AM, Bruno Marchal wrote: PA is a reality, by itself, indeed an existing Löbian machine, and PA talks about a reality which is vaster than PA, and that no machine can grasp in its entirety. You confuse theory and model here. You can't kick Peano's axioms. What is your point? That things don't exist unless you can kick them? Real things kick back. Maths kicks back... Only metaphorically. The laws of physics prevent you from traveling at a speed more than ~300,000,000 m/s. A curious choice. The 'laws of physics' say light travels the same speed in vacuo in all frames. The number 299,792,458 is just an arbitrary conversion factor between meters and seconds. The laws of arithmetic prevent you from writing down more than 2 distinct factors of 17. 17 = (17/4)*4 I've got a million of'em. Brent They seem equally forceful, each in their own way. The laws of mathematics may be even more forceful, for it is conceivable in some physical universe you can go faster than the speed of light in this universe, it is much harder to conceive of a universe where you could write down a third factor of 17. Jason -- 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: What are wavefunctions?
On 18 January 2014 19:45, meekerdb meeke...@verizon.net wrote: On 1/17/2014 10:16 PM, Jason Resch wrote: The laws of arithmetic prevent you from writing down more than 2 distinct factors of 17. 17 = (17/4)*4 I've got a million of'em. ... using integers, which we know were created by God, rather than man-made fractions :-) -- 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: What are wavefunctions?
On 15 Jan 2014, at 21:11, meekerdb wrote: On 1/15/2014 4:13 AM, Bruno Marchal wrote: I am not convinced, as I tend to not believe in any primitive time and space, at least when I tend to believe in comp (of course I *know* nothing). QM is indeed reversible (in large part), but using this to select one branch by boundary condition, is still like a form of cosmic solipsism to me. We can't refute it, and unlike most QM collapse theories, we can't criticize it from locality and determinacy, but that does not yet make it convincing compare to MW, and infinitely more so in the comp frame, where we can't avoid the many dreams. It's just information from the future - which is exactly the same thing as true randomness, and both are operationally the same as FPI. That's why I think an advancement in QM interpretation would be to derive probability. Comp provides an explanation of randomness, but it's not clear to me that it implies a complex Hilbert space. It should, but even the orthomodularity quantum tatutology is still non tractable. So it not *yet* clear, but that question has been reformulated in purely arithmetical terms. The arithmetical quantization []p (with p sigma_1, and []p = Bp Dp p, for example. B = Gödel's beweisbar) dtermine the answer, alas, still unknown. 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/groups/opt_out. 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/groups/opt_out.
Re: What are wavefunctions?
On 16 January 2014 20:00, meekerdb meeke...@verizon.net wrote: On 1/15/2014 7:08 PM, LizR wrote: On 16 January 2014 14:11, meekerdb meeke...@verizon.net wrote: You can do that (in fact it may have been done). You have two emitters with polarizers and a detector at which you post-select only those particles that arrive and form a singlet. Then you will find that the correlation counts for that subset violates Bell's inequality for polarizer settings of 30, 60, 120deg. I assume that means Price's (and Bell's) assumption that violations of Bell's inequality can be explained locally and realistically with time symmetry is definitely wrong...? ?? Why do you conclude that? It's the time-reverse of the EPR that violated BI. Because as I (perhaps mis-) understand it, Price claims that we need to take both past AND future boundary conditions into account to explain EPR with time symmetry. If we can explain it with only a forward in time or backward in time explanation, then we aren't using both. Or I may be missing the point. That often happens. Now that I think about it, I probably am. I shall go into the garden and eat worms, and while I tuck in maybe you could explain to me whether I jumped to completely the wrong conclusion. -- 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: What are wavefunctions?
On 16 Jan 2014, at 01:57, meekerdb wrote: On 1/15/2014 4:03 PM, LizR wrote: By the way, I may have this wrong but it seems to me your hyperdeterminism objection is an objection to block universes generally. I can't see how the big crunch (or timelike infinity) being a boundary condition on the universe is a problem in a block universe (or multiverse) ...? I think Bruno is thinking of a tree-like branching block multiverse so there can still be FPI due to the branches. yes, like in arithmetic. Otherwise definite, random things have to happen in realizing the block universe - and Bruno hates random things and he likes infinities, Well, let us say that I hate only the *assumption* of 3p randomness. Einstein define insanity by such belief (of course that is not an argument). so... But you should read L.S. Schulman's solution to the problem of randomness. He speculates that within the domain of a state we can prepare, which is of measure hbar=/=0, there are special states which are causally connected to *future* states and when we choose a measurement in the future we are selecting out one of these special states. Is that not already the case in the WM duplication experiment? The problem is not in the selection, but in a physical mechanism making disappear the realities not selected. They always need to add something to the equation, be it a guiding potential, boundary conditions, etc. 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/groups/opt_out. 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/groups/opt_out.
Re: What are wavefunctions?
On 16 Jan 2014, at 04:05, Jason Resch wrote: Hyper determinism makes little sense as a serious theory to me. Why should particle properties conform to what a computer's random number generator outputs, and then the digits of Pi, and then the binary expansion of the square root of 2, all variously as the experimenters change the knobs as to what determines the spin axis of the lepton their analyzer measures. Are radioactive decays of particles really such things that are governed by the behavior of a selected random source, or alternately, are they really such things that govern what the digits of Pi or the square root of 2 are? Yes, that's my point. Price make a logical point, though. But we have to abandon QM for QM + a lot of extra-information to select one reality. In that case why not come back to Ptolemeaus. The idea that it is the sun which moves in the sky is consistent too, even with Newton physics, if you put enough extra-data in the theory. With one reality, a quantum computer works only because of extra- magical boundary conditions. Bruno Jason On Wed, Jan 15, 2014 at 6:13 AM, Bruno Marchal marc...@ulb.ac.be wrote: On 15 Jan 2014, at 11:10, LizR wrote: On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. The setting of the analyser must be predetermined. And not in the mechanist sense, where the choice of the analyser is still made by you, even if deterministically so. With only one branch, you are not just using irreversibility, but you are using the boundary condition selecting a branch among all in the universal wave. These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Those are still many-world theories, + some ugly selection principle to get one branch. It is very not natural, as you have quasi microsuperposition (appearance of many branches), but the macro-one are eliminated by ad hoc boundary conditions, which will differ depending on where you will decide to introduce the Heisenberg cut. Also, QM will prevent us to know or measure those boundary conditions, which makes them into (local, perhaps, in *some* sense) hidden variable theory. I don't understand the above. The theory is simply QM with no collapse and with no preferred time direction (it assumes any system which violates Bell's inequality has to operate below the level where decoherence brings in the effects of the entropy gradient). It is both local and realistic, since time symmetry is Bell's 4th assumption - it allows EPR experiments to be local and realistic (I am relying on John Bell for this information, I wouldn't be able to work it out myself). So it definitely is a hidden variable theory. Yes, and I am willing to accept it is local. but it is hyper- determined. It means that if I chose the setting of the two analyser in the Aspect experience by looking at my horoscope, that horoscope was determined by the whole future of the phsyical universe. Logically possible, you are right, but ugly, as it is a selection principle based on boundary conditions. It is more local than Bohm, and it does not need a new potential, but it is sill using abnormal special data for the TOE. It is no more a nice and gentle equation like the SWE, but that same equation together with tuns of mega-terra-gigabyte of data. I think for it to work the system is kept from undergoing decoherence or any interaction that would lead to MWI branching. EPR experiments only appear to work for systems that are shielded from such effects, I think? So there isn't a problem with the MWI - the whole thing takes place in one branch, with no quantum interfence etc being relevant. (I believe that EPR experiments lose their ability to violate Bell's inequality once interactions occur that could cause MWI branching within the system under consideration???) ? Many worlds is far less ad-hoc, imo. There is no Heisenberg cut, and the boundary conditions does not play any special role, and indeed they are all realized in the universal wave (and in
Re: What are wavefunctions?
On Tue, Jan 14, 2014 at 2:09 PM, meekerdb meeke...@verizon.net wrote: It [entropy] is NOT the log of the number of ways a macro-state could form. That would be ambiguous in any case (do different order of events count as different ways? Yes obviously. the Boltzmann formula shows the relationship between entropy and the number of ways system can be arranged Most experts say there is only one way a Black Hole can be arranged because it has no parts, or if it does the experts can't agree on exactly what those parts are, see Susskind's The Black Hole Wars. So for now it's best to say entropy is the logarithm of the ways it could have been made. To say it only has mass, charge, and angular momentum is just to give a classical macro-state description It's the best we can do. Perhaps when we find a quantum theory of gravity we can say more, but not now. 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/groups/opt_out.
Re: What are wavefunctions?
On 1/15/2014 11:42 PM, Jason Resch wrote: On Thu, Jan 16, 2014 at 12:58 AM, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/15/2014 7:05 PM, Jason Resch wrote: Hyper determinism makes little sense as a serious theory to me. Why should particle properties conform to what a computer's random number generator outputs, and then the digits of Pi, and then the binary expansion of the square root of 2, all variously as the experimenters change the knobs as to what determines the spin axis of the lepton their analyzer measures. Are radioactive decays of particles really such things that are governed by the behavior of a selected random source, or alternately, are they really such things that govern what the digits of Pi or the square root of 2 are? They are all part of the same reality. Are they? Aren't numbers like Pi and sqrt(2) beyond the reality of QM, or rather, more fundamental than it? The moment you admit numbers like Pi into your reality, you get much more than just QM. Of course QM is just a model of how we think the world works...like arithmetic is a model of countable things. Neither one is *reality*. You assume its the experimental choice of measurement that determines the particles response, but I think the picture is supposed to be that both the particle in the experiment and the particles making up the experimenter are determined by the same laws. So how, when using the digits of Pi to decide whether to measure the x-axis, or the y-axis, does the particle (when it decays), know to have both electron and positron agree measured on some axis, when that axis is determined by some relation between a circle and its diameter? Here the laws involved seemed to go beyond physical laws, it introduces mathematical laws, which can selectively be made to control/guide physics.. They only 'seem to' because you neglect the fact that in the experiment you don't use the digits of pi from Platonia, you use their physical instantiation as calculated in the registers of a computer or written ink on a page. 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/groups/opt_out.
Re: What are wavefunctions?
On Thu, Jan 16, 2014 at 11:53 AM, meekerdb meeke...@verizon.net wrote: On 1/15/2014 11:42 PM, Jason Resch wrote: On Thu, Jan 16, 2014 at 12:58 AM, meekerdb meeke...@verizon.net wrote: On 1/15/2014 7:05 PM, Jason Resch wrote: Hyper determinism makes little sense as a serious theory to me. Why should particle properties conform to what a computer's random number generator outputs, and then the digits of Pi, and then the binary expansion of the square root of 2, all variously as the experimenters change the knobs as to what determines the spin axis of the lepton their analyzer measures. Are radioactive decays of particles really such things that are governed by the behavior of a selected random source, or alternately, are they really such things that govern what the digits of Pi or the square root of 2 are? They are all part of the same reality. Are they? Aren't numbers like Pi and sqrt(2) beyond the reality of QM, or rather, more fundamental than it? The moment you admit numbers like Pi into your reality, you get much more than just QM. Of course QM is just a model of how we think the world works...like arithmetic is a model of countable things. Neither one is *reality*. You assume its the experimental choice of measurement that determines the particles response, but I think the picture is supposed to be that both the particle in the experiment and the particles making up the experimenter are determined by the same laws. So how, when using the digits of Pi to decide whether to measure the x-axis, or the y-axis, does the particle (when it decays), know to have both electron and positron agree measured on some axis, when that axis is determined by some relation between a circle and its diameter? Here the laws involved seemed to go beyond physical laws, it introduces mathematical laws, which can selectively be made to control/guide physics.. They only 'seem to' because you neglect the fact that in the experiment you don't use the digits of pi from Platonia, you use their physical instantiation as calculated in the registers of a computer or written ink on a page. And what is the physical link between the computer's registers and the radioactive decay? What keeps it from breaking down in the next moment? If all that information has to be assumed at the start, there's no reason an equally big description would be any less likely, and thus there is no reason it shouldn't diverge from our expectations in the next second. (Also, I would say they do come from Platonia, in that the platonic properties of Pi (which the computer is inspecting and reporting) prevents the computer from outputting the digits of some other number. Consider that the numbers of Pi go on forever and have an infinite expansion, but there is no physical way to realize that expansion. In that sense, the digits of Pi transcends our own physics and must be outside/beyond it.) Jason -- 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: What are wavefunctions?
On 1/16/2014 1:48 AM, LizR wrote: On 16 January 2014 20:00, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/15/2014 7:08 PM, LizR wrote: On 16 January 2014 14:11, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: You can do that (in fact it may have been done). You have two emitters with polarizers and a detector at which you post-select only those particles that arrive and form a singlet. Then you will find that the correlation counts for that subset violates Bell's inequality for polarizer settings of 30, 60, 120deg. I assume that means Price's (and Bell's) assumption that violations of Bell's inequality can be explained locally and realistically with time symmetry is definitely wrong...? ?? Why do you conclude that? It's the time-reverse of the EPR that violated BI. Because as I (perhaps mis-) understand it, Price claims that we need to take both past AND future boundary conditions into account to explain EPR with time symmetry. If we can explain it with only a forward in time or backward in time explanation, then we aren't using both. But in the reverse EPR we are in effect using both past and future boundary conditions. At the emitters we set the polarizers - that's the past boundary condition. At the single detector we post-select only those incoming pairs that form a net-zero spin; so that's a future boundary condition. This is only a 'thought experiment' because I don't think there's any practical way to capture and test pairs for net-zero spin. Note that you must NOT measure the spins, you have to select the net-zero pair without measuring either one. Brent Or I may be missing the point. That often happens. Now that I think about it, I probably am. I shall go into the garden and eat worms, and while I tuck in maybe you could explain to me whether I jumped to completely the wrong conclusion. -- 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: What are wavefunctions?
On 17 January 2014 07:56, meekerdb meeke...@verizon.net wrote: On 1/16/2014 1:48 AM, LizR wrote: On 16 January 2014 20:00, meekerdb meeke...@verizon.net wrote: On 1/15/2014 7:08 PM, LizR wrote: On 16 January 2014 14:11, meekerdb meeke...@verizon.net wrote: You can do that (in fact it may have been done). You have two emitters with polarizers and a detector at which you post-select only those particles that arrive and form a singlet. Then you will find that the correlation counts for that subset violates Bell's inequality for polarizer settings of 30, 60, 120deg. I assume that means Price's (and Bell's) assumption that violations of Bell's inequality can be explained locally and realistically with time symmetry is definitely wrong...? ?? Why do you conclude that? It's the time-reverse of the EPR that violated BI. Because as I (perhaps mis-) understand it, Price claims that we need to take both past AND future boundary conditions into account to explain EPR with time symmetry. If we can explain it with only a forward in time or backward in time explanation, then we aren't using both. But in the reverse EPR we are in effect using both past and future boundary conditions. At the emitters we set the polarizers - that's the past boundary condition. At the single detector we post-select only those incoming pairs that form a net-zero spin; so that's a future boundary condition. I must admit I thought you were saying we could do it using ONLY the future boundary conditions. If you use both then you should logically use both in the forwards case, too, so I assume Price's explanation still stands. -- 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: What are wavefunctions?
On 1/16/2014 4:02 AM, Bruno Marchal wrote: Yes, that's my point. Price make a logical point, though. But we have to abandon QM for QM + a lot of extra-information to select one reality. In that case why not come back to Ptolemeaus. The idea that it is the sun which moves in the sky is consistent too, even with Newton physics, if you put enough extra-data in the theory. It's not only consistent it is so in the frame used when modeling the galaxy. Because the physics is invariant under various transforms one always transforms so as to make the problem easier. 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/groups/opt_out.
Re: What are wavefunctions?
On Wed, Jan 15, 2014 at 7:08 PM, LizR lizj...@gmail.com wrote: On 16 January 2014 03:51, Jesse Mazer laserma...@gmail.com wrote: On Wed, Jan 15, 2014 at 5:10 AM, LizR lizj...@gmail.com wrote: On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Time symmetry in the laws of physics alone, without any special restriction on boundary conditions, can't get you violation of Bell inequalities. Ordinary time symmetry doesn't mean you have to take into account both future and past to determine what happens in a given region of spacetime after all, it just means you can deduce it equally well going in *either* direction. So in a deterministic time-symmetric theory (Price's speculations about hidden variables are at least compatible with determinism) it's still true that what happens in any region of spacetime can be determined entirely by events in its past light cone, say the ones occurring at some arbitrarily-chosen initial tim. This means that in a Price-like theory where measurement results are explained in terms of hidden variables the particles carry with them from emitter to experimenters, it must be true that the original assignment of the hidden variables to each particle at the emitter is determined by the past light cone of the event of each particle leaving the emitter. Meanwhile, the event of an experimenter choosing which measurement to perform will have its own past light cone, and there are plenty of events in the past light cone of the choice that do *not* lie in the past light cone of the particles leaving the emitter. So, without any restriction on boundary conditions, one can choose an ensemble of possible initial conditions with the following properties: 1. The initial states of all points in space that line in the past light cone of the particles leaving the emitter are identical for each member of the ensemble, so in every possible history generated from these initial conditions, the particles have the same hidden variables associated with them. 2. The initial states of points in space that lie in the past light cone of the experimenters choosing what spin direction to measure vary in different members of the ensemble, in such a way that all combinations of measurement choices are represented in different histories chosen from this ensemble. If both these conditions apply, Bell's proofs that various inequalities shouldn't be violated works just fine--for example, there's no combination of hidden variables you can choose for the particle pair that ensure that in all the histories where the experimenters measure along the *same* axis they get opposite results (spin-up for one experimenter, spin-down for the other) with probability 1, but in all the histories where they measure along two *different* axes they have less than a 1/3 chance of getting opposite results. Only by having the hidden variables assigned during emission be statistically correlated to the choices the experimenters later make about measurements can Price's argument work, and the argument above shows that time-symmetry without special boundary conditions won't suffice for this. If you're right then Price is wrong. However I don't recall him saying that the only consequence of time symmetry is that events can be, so to speak, worked backwards equally well. In particular, I read his EPR explanation as showing that both future and past boundary conditions were relevant in explaining the violations of B's Inequality. The forwards-and-backwards version would prevent time symmetry having any detectable effects, as far as I can see. (Also I'd like to see an explanation of EPR which works backwards from the measurement settings to the emitter and explains the violation of B's Inequality. That would definitely be a clincher!) I don't think my argument necessarily conflicts with Price, since I don't remember him clearly saying that the Bell inequality violations could be resolved without time-symmetric boundary conditions alongside time-symmetric
Re: What are wavefunctions?
On 17 January 2014 08:40, Jesse Mazer laserma...@gmail.com wrote: On Wed, Jan 15, 2014 at 7:08 PM, LizR lizj...@gmail.com wrote: On 16 January 2014 03:51, Jesse Mazer laserma...@gmail.com wrote: (SNIP) Still, the fact remains that if your local realistic time-symmetric theory of physics *is* a dynamical one where later conditions can be derived from initial conditions, then the argument I made in the previous comment you quoted should still apply, and in that case time-symmetry without very specially-chosen initial boundary conditions will be of no help in explaining how Bell's inequality can be violated. So it's not correct to just say that Bell assumed time was asymmetric, and thus that the type of time-symmetry we see in *existing* theories of physics like quantum field theory is enough to discount his proof. In terms of a Venn diagram, there would be an overlap between the circle time-symmetric (or CPT-symmetric) local realistic theories and theories that satisfy the assumptions of Bell's proof, and all existing time-symmetric theories (except for general relativity in non-globally-hyperbolic spacetimes) would fall into that overlap region. Price may be correct that the general *idea* of time-symmetry points to a possible loophole in Bell's proof, but taking advantage of this loophole would require a new and different type of time-symmetric theory from the ones physicists have used in the past to model real-world situations. I don't *think* Price is thinking of a dynamical theory (assuming I've understood you correctly) ... But in any case, please note that in quoting Price I am not proposing an explanation, or even taking a position, I am only pointing out that there is the logical possibility that an explanation could be constructed on this basis. So, I am merely pointing out that when someone says Bell made exactly 3 assumptions... that isn't true, so anything we deduce on the basis of him having made exactly 3 assumptions will be false (or at best, only accidentally true). And hence, until the 4th assumption is either incorportated into an explanation of BI violations, or shown to be irrelevant to them, we will not be in a position to say EPR shows that physics is either non-local or non-realistic. Everything else I've said on this subject has been in response to people trying to argue that physics is not time symmetric. So far all such arguments have been a variant on the second law says so and my response has been a variant on the second law emerges above the level at which we can detect time symmetry. (Plus I've invoked boundary conditions on the universe to explain how the second law can arise from time symmetric physics...) However, I don't have the technical knowledge to either construct an explanation of EPR on this basis, or to show that one can't be constructed. But I do think it's high time someone did, if they haven't already done so. -- 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: What are wavefunctions?
On 1/16/2014 10:32 AM, Jason Resch wrote: They only 'seem to' because you neglect the fact that in the experiment you don't use the digits of pi from Platonia, you use their physical instantiation as calculated in the registers of a computer or written ink on a page. And what is the physical link between the computer's registers and the radioactive decay? They have common events in their past light cone. What keeps it from breaking down in the next moment? Why are there regularities that can be represented by the laws of phyiscs? Dunno. 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/groups/opt_out.
Re: What are wavefunctions?
On 17 January 2014 12:31, meekerdb meeke...@verizon.net wrote: On 1/16/2014 10:32 AM, Jason Resch wrote: They only 'seem to' because you neglect the fact that in the experiment you don't use the digits of pi from Platonia, you use their physical instantiation as calculated in the registers of a computer or written ink on a page. And what is the physical link between the computer's registers and the radioactive decay? They have common events in their past light cone. What keeps it from breaking down in the next moment? Why are there regularities that can be represented by the laws of phyiscs? Dunno. One can probably imagine answers with a little effort (WAP, parsimony...) but Dunno is the honest answer. -- 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: What are wavefunctions?
On 1/16/2014 11:00 AM, LizR wrote: On 17 January 2014 07:56, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/16/2014 1:48 AM, LizR wrote: On 16 January 2014 20:00, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/15/2014 7:08 PM, LizR wrote: On 16 January 2014 14:11, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: You can do that (in fact it may have been done). You have two emitters with polarizers and a detector at which you post-select only those particles that arrive and form a singlet. Then you will find that the correlation counts for that subset violates Bell's inequality for polarizer settings of 30, 60, 120deg. I assume that means Price's (and Bell's) assumption that violations of Bell's inequality can be explained locally and realistically with time symmetry is definitely wrong...? ?? Why do you conclude that? It's the time-reverse of the EPR that violated BI. Because as I (perhaps mis-) understand it, Price claims that we need to take both past AND future boundary conditions into account to explain EPR with time symmetry. If we can explain it with only a forward in time or backward in time explanation, then we aren't using both. But in the reverse EPR we are in effect using both past and future boundary conditions. At the emitters we set the polarizers - that's the past boundary condition. At the single detector we post-select only those incoming pairs that form a net-zero spin; so that's a future boundary condition. I must admit I thought you were saying we could do it using ONLY the future boundary conditions. If you use both then you should logically use both in the forwards case, too, so I assume Price's explanation still stands. You do use both in the forward case, but people kind of slide over the initial condition which is that you produce two particles with net-zero spin. It might seem more symmetric if we did the forward case by creating a lot of pairs and only selecting the net spin-zero pairs to go to the EPR detectors. 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/groups/opt_out.
Re: What are wavefunctions?
On 17 January 2014 12:42, meekerdb meeke...@verizon.net wrote: You do use both in the forward case, but people kind of slide over the initial condition which is that you produce two particles with net-zero spin. It might seem more symmetric if we did the forward case by creating a lot of pairs and only selecting the net spin-zero pairs to go to the EPR detectors. I can kind of see how (in this explanation) this would merge the information from the future, so the particles could effectively influence each other at a distance at the detectors. -- 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: What are wavefunctions?
On Thu, Jan 16, 2014 at 5:31 PM, meekerdb meeke...@verizon.net wrote: On 1/16/2014 10:32 AM, Jason Resch wrote: They only 'seem to' because you neglect the fact that in the experiment you don't use the digits of pi from Platonia, you use their physical instantiation as calculated in the registers of a computer or written ink on a page. And what is the physical link between the computer's registers and the radioactive decay? They have common events in their past light cone. But is that enough to explain the link? It permits a non-superluminal link, but what is that link, if not some spooky, invisible, causal-agreement-enforcening mechanism? What keeps it from breaking down in the next moment? Why are there regularities that can be represented by the laws of phyiscs? Dunno. But here, there regularities are not from following from any laws, at least not compressible ones. Jason 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/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: What are wavefunctions?
On 1/16/2014 4:46 PM, Jason Resch wrote: On Thu, Jan 16, 2014 at 5:31 PM, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/16/2014 10:32 AM, Jason Resch wrote: They only 'seem to' because you neglect the fact that in the experiment you don't use the digits of pi from Platonia, you use their physical instantiation as calculated in the registers of a computer or written ink on a page. And what is the physical link between the computer's registers and the radioactive decay? They have common events in their past light cone. But is that enough to explain the link? It permits a non-superluminal link, but what is that link, if not some spooky, invisible, causal-agreement-enforcening mechanism? Dunno, but it needn't be spooky; since the detectors, polarizers, emitters, experiment, are all macroscopic and semi-classical they presumably are entangled with everything in their past light cones via ordinary QM particle/fields - that's the hypothesis of how decoherence can split the Everett world into quasi-classical ones we can experience. Brent What keeps it from breaking down in the next moment? Why are there regularities that can be represented by the laws of phyiscs? Dunno. But here, there regularities are not from following from any laws, at least not compressible ones. Jason 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 mailto:everything-list%2bunsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com mailto: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. -- 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: What are wavefunctions?
On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. Those are still many-world theories, + some ugly selection principle to get one branch. It is very not natural, as you have quasi microsuperposition (appearance of many branches), but the macro-one are eliminated by ad hoc boundary conditions, which will differ depending on where you will decide to introduce the Heisenberg cut. Also, QM will prevent us to know or measure those boundary conditions, which makes them into (local, perhaps, in *some* sense) hidden variable theory. Many worlds is far less ad-hoc, imo. There is no Heisenberg cut, and the boundary conditions does not play any special role, and indeed they are all realized in the universal wave (and in arithmetic). Bruno On 15 January 2014 10:01, LizR lizj...@gmail.com wrote: On 15 January 2014 06:11, John Clark johnkcl...@gmail.com wrote: On Sun, Jan 12, 2014 at 6:41 PM, LizR lizj...@gmail.com wrote: Retro-causality (time symmetry is a better term) only exists at the quantum level. Why? Where is the dividing line? And with a Schrodinger's Cat type device a quantum event can easily be magnified to a macro-event as large as desired, you could connect it up to an H-bomb. The dividing line appears to be roughly where decoherence occurs. Basically anything above a single quantum entity engaged in a carefully controlled interaction is liable to get its time symmetric properties washed out by interactions with other particles The nucleus of an atom is tiny even by atomic standards so it is certainly at the quantum level, and in its natural state of existing inside a huge chunk of irregular gyrating matter this tiny thing is constantly subject to the slings and arrows of outrageous fortune from an astronomical number of other clumsy atoms; and yet the half life of Bismuth 209 is 1.9 * 10^19 years. Why? Because that's how long it takes for the relevant particles to get over the potential barrier. But this is irrelevant. Atomic nuclei are (probably) already on the wrong side of the entropy fence in any case. They're bound states which can only occur under certain special cirumstances, namely when the universe expands and cools enough to allow them to form. And atomic nuclei haven't been used to violate Bell's inequality as far as I know. It's just a fact, if time were symmetrical then you'd be just as good at predicting the future as you are at remembering the past, so you'd know the outcome of an experiment before you performed it just as well as you remember setting up the apparatus. But this is not the way things are because the second law exists. And the second law exists because of low entropy initial conditions. And I don't know why there were low entropy initial conditions. OK. So the above statement of yours about predicting the future is still false, Yes it's false, I don't think this will come as a great news flash but the truth is we're not as good at predicting the future as we are at remembering the past. And the reason we're not is that time is not symmetrical. Except below the level of coarse graining at which entropy operates, that is correct. And I never claimed otherwise. As I keep saying, I'm only claiming this is relevant in special circumstances like EPR experiments. To recap briefly -- the laws of physics are time symmetrical, Yes, the fundamental laws of physics, the ones we know anyway, seem to be time symmetrical. But that doesn't mean that time is symmetrical. ...is just words. Stop nitpicking. If the laws of physics are time symmetrical, that has a potential influence on EPR experiments. and most particle interactions are constrained by boundary conditions. Yes, and that is why time is NOT symmetrical. Stop playing with words. The time symmetry of fundamental physics is there, so it's perfectly valid to say time is symmetrical below the level of coarse graining needed to derive the 2nd law, and asymmetrical above it. (That's virtually a simple restatement of Boltzmann's H-theorem for dummies.) The point is that symmetrical time may become apparent in EPR setups. You haven't yet given even a suggestion of a reason why it wouldn't, just a load of hand waving about stuff that is IRRELEVANT to EPR experiments, which are carefully prepared to avoid all the influences you've mentioned. Now how about discussing what I've actually claimed,
Re: What are wavefunctions?
On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Those are still many-world theories, + some ugly selection principle to get one branch. It is very not natural, as you have quasi microsuperposition (appearance of many branches), but the macro-one are eliminated by ad hoc boundary conditions, which will differ depending on where you will decide to introduce the Heisenberg cut. Also, QM will prevent us to know or measure those boundary conditions, which makes them into (local, perhaps, in *some* sense) hidden variable theory. I don't understand the above. The theory is simply QM with no collapse and with no preferred time direction (it assumes any system which violates Bell's inequality has to operate below the level where decoherence brings in the effects of the entropy gradient). It is both local and realistic, since time symmetry is Bell's 4th assumption - it allows EPR experiments to be local and realistic (I am relying on John Bell for this information, I wouldn't be able to work it out myself). So it definitely is a hidden variable theory. I think for it to work the system is kept from undergoing decoherence or any interaction that would lead to MWI branching. EPR experiments only appear to work for systems that are shielded from such effects, I think? So there isn't a problem with the MWI - the whole thing takes place in one branch, with no quantum interfence etc being relevant. (I believe that EPR experiments lose their ability to violate Bell's inequality once interactions occur that could cause MWI branching within the system under consideration???) Many worlds is far less ad-hoc, imo. There is no Heisenberg cut, and the boundary conditions does not play any special role, and indeed they are all realized in the universal wave (and in arithmetic). Please explain about the Heisenberg cut. I've heard the term, but don't know how it relates to EPR experiments. Have you read Huw Price's book Time's arrow and Archimedes' Point ? -- 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: What are wavefunctions?
On 15 Jan 2014, at 11:10, LizR wrote: On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. The setting of the analyser must be predetermined. And not in the mechanist sense, where the choice of the analyser is still made by you, even if deterministically so. With only one branch, you are not just using irreversibility, but you are using the boundary condition selecting a branch among all in the universal wave. These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Those are still many-world theories, + some ugly selection principle to get one branch. It is very not natural, as you have quasi microsuperposition (appearance of many branches), but the macro-one are eliminated by ad hoc boundary conditions, which will differ depending on where you will decide to introduce the Heisenberg cut. Also, QM will prevent us to know or measure those boundary conditions, which makes them into (local, perhaps, in *some* sense) hidden variable theory. I don't understand the above. The theory is simply QM with no collapse and with no preferred time direction (it assumes any system which violates Bell's inequality has to operate below the level where decoherence brings in the effects of the entropy gradient). It is both local and realistic, since time symmetry is Bell's 4th assumption - it allows EPR experiments to be local and realistic (I am relying on John Bell for this information, I wouldn't be able to work it out myself). So it definitely is a hidden variable theory. Yes, and I am willing to accept it is local. but it is hyper- determined. It means that if I chose the setting of the two analyser in the Aspect experience by looking at my horoscope, that horoscope was determined by the whole future of the phsyical universe. Logically possible, you are right, but ugly, as it is a selection principle based on boundary conditions. It is more local than Bohm, and it does not need a new potential, but it is sill using abnormal special data for the TOE. It is no more a nice and gentle equation like the SWE, but that same equation together with tuns of mega-terra-gigabyte of data. I think for it to work the system is kept from undergoing decoherence or any interaction that would lead to MWI branching. EPR experiments only appear to work for systems that are shielded from such effects, I think? So there isn't a problem with the MWI - the whole thing takes place in one branch, with no quantum interfence etc being relevant. (I believe that EPR experiments lose their ability to violate Bell's inequality once interactions occur that could cause MWI branching within the system under consideration???) ? Many worlds is far less ad-hoc, imo. There is no Heisenberg cut, and the boundary conditions does not play any special role, and indeed they are all realized in the universal wave (and in arithmetic). Please explain about the Heisenberg cut. I've heard the term, but don't know how it relates to EPR experiments. The Heinsenberg cut is where the wave should collapse in the Copenhagen QM. Von Neumann understood well that it is largely arbitrary. In all one world theory, you have to justify why the superposition works so well for the micro-worlds, and disappear for the macro- world. Using reversiblity, cannot by itself solve that problem. What works is reversibility and the boundaries conditions. God needs to know all the detail of the big crunch to program convenably the big bang, so as making an Aspect result consistent with one-world, locality and determinacy. Have you read Huw Price's book Time's arrow and Archimedes' Point ? No. I know it, as it is often discussed on forums. I am not convinced, as I tend to not believe in any primitive time and space, at least when I tend to believe in comp (of course I *know* nothing). QM is indeed reversible (in large part), but using this to select one branch by boundary condition, is still like a form of cosmic solipsism to me. We can't refute it, and unlike most QM collapse theories, we
Re: What are wavefunctions?
On Wed, Jan 15, 2014 at 5:10 AM, LizR lizj...@gmail.com wrote: On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Time symmetry in the laws of physics alone, without any special restriction on boundary conditions, can't get you violation of Bell inequalities. Ordinary time symmetry doesn't mean you have to take into account both future and past to determine what happens in a given region of spacetime after all, it just means you can deduce it equally well going in *either* direction. So in a deterministic time-symmetric theory (Price's speculations about hidden variables are at least compatible with determinism) it's still true that what happens in any region of spacetime can be determined entirely by events in its past light cone, say the ones occurring at some arbitrarily-chosen initial tim. This means that in a Price-like theory where measurement results are explained in terms of hidden variables the particles carry with them from emitter to experimenters, it must be true that the original assignment of the hidden variables to each particle at the emitter is determined by the past light cone of the event of each particle leaving the emitter. Meanwhile, the event of an experimenter choosing which measurement to perform will have its own past light cone, and there are plenty of events in the past light cone of the choice that do *not* lie in the past light cone of the particles leaving the emitter. So, without any restriction on boundary conditions, one can choose an ensemble of possible initial conditions with the following properties: 1. The initial states of all points in space that line in the past light cone of the particles leaving the emitter are identical for each member of the ensemble, so in every possible history generated from these initial conditions, the particles have the same hidden variables associated with them. 2. The initial states of points in space that lie in the past light cone of the experimenters choosing what spin direction to measure vary in different members of the ensemble, in such a way that all combinations of measurement choices are represented in different histories chosen from this ensemble. If both these conditions apply, Bell's proofs that various inequalities shouldn't be violated works just fine--for example, there's no combination of hidden variables you can choose for the particle pair that ensure that in all the histories where the experimenters measure along the *same* axis they get opposite results (spin-up for one experimenter, spin-down for the other) with probability 1, but in all the histories where they measure along two *different* axes they have less than a 1/3 chance of getting opposite results. Only by having the hidden variables assigned during emission be statistically correlated to the choices the experimenters later make about measurements can Price's argument work, and the argument above shows that time-symmetry without special boundary conditions won't suffice for this. Jesse Those are still many-world theories, + some ugly selection principle to get one branch. It is very not natural, as you have quasi microsuperposition (appearance of many branches), but the macro-one are eliminated by ad hoc boundary conditions, which will differ depending on where you will decide to introduce the Heisenberg cut. Also, QM will prevent us to know or measure those boundary conditions, which makes them into (local, perhaps, in *some* sense) hidden variable theory. I don't understand the above. The theory is simply QM with no collapse and with no preferred time direction (it assumes any system which violates Bell's inequality has to operate below the level where decoherence brings in the effects of the entropy gradient). It is both local and realistic, since time symmetry is Bell's 4th assumption - it allows EPR experiments to be local and realistic (I am relying on John Bell for this information, I wouldn't be able to work it out myself). So it definitely is a hidden variable theory. I think for it to work
Re: What are wavefunctions?
On Wed, Jan 15, 2014 at 7:13 AM, Bruno Marchal marc...@ulb.ac.be wrote: On 15 Jan 2014, at 11:10, LizR wrote: On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. The setting of the analyser must be predetermined. And not in the mechanist sense, where the choice of the analyser is still made by you, even if deterministically so. With only one branch, you are not just using irreversibility, but you are using the boundary condition selecting a branch among all in the universal wave. In Wheeler's 'ItBit' empirical quantum model, that is because in controlled experiments the detector observers on the detection plane all ask the same question, thereby always selecting the same spacetime/branch for photon statistics. These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Those are still many-world theories, + some ugly selection principle to get one branch. It is very not natural, as you have quasi microsuperposition (appearance of many branches), but the macro-one are eliminated by ad hoc boundary conditions, which will differ depending on where you will decide to introduce the Heisenberg cut. Also, QM will prevent us to know or measure those boundary conditions, which makes them into (local, perhaps, in *some* sense) hidden variable theory. I don't understand the above. The theory is simply QM with no collapse and with no preferred time direction (it assumes any system which violates Bell's inequality has to operate below the level where decoherence brings in the effects of the entropy gradient). It is both local and realistic, since time symmetry is Bell's 4th assumption - it allows EPR experiments to be local and realistic (I am relying on John Bell for this information, I wouldn't be able to work it out myself). So it definitely is a hidden variable theory. Yes, and I am willing to accept it is local. but it is hyper-determined. It means that if I chose the setting of the two analyser in the Aspect experience by looking at my horoscope, that horoscope was determined by the whole future of the phsyical universe. Logically possible, you are right, but ugly, as it is a selection principle based on boundary conditions. It is more local than Bohm, and it does not need a new potential, but it is sill using abnormal special data for the TOE. It is no more a nice and gentle equation like the SWE, but that same equation together with tuns of mega-terra-gigabyte of data. Same comment as above but now controlled experiments also use the gentle equation like the SWE', but still in the context of an MWI reality. Richard I think for it to work the system is kept from undergoing decoherence or any interaction that would lead to MWI branching. EPR experiments only appear to work for systems that are shielded from such effects, I think? So there isn't a problem with the MWI - the whole thing takes place in one branch, with no quantum interfence etc being relevant. (I believe that EPR experiments lose their ability to violate Bell's inequality once interactions occur that could cause MWI branching within the system under consideration???) A recent paper suggests that decoherence in the experiment particle preparations are a stronger source of branching than decoherence in the detector. In terms of Wheeler theory, that amounts to the initial observer, the prepemit particle observer, being more capable of producing branching by asking a variety of questions (decohered questions) or even random questions, than the final detector observer asking just random questions is capable of producing branching.. http://phys.org/news/2014-01-quantum-to-classical-transition-fuzziness.html ? Many worlds is far less ad-hoc, imo. There is no Heisenberg cut, and the boundary conditions does not play any special role, and indeed they are all realized in the universal wave (and in arithmetic). Please explain about the Heisenberg cut. I've heard the term, but don't know how it relates to EPR experiments. The Heinsenberg cut is where the wave should collapse in the Copenhagen QM. Von Neumann
Re: What are wavefunctions?
On 1/15/2014 4:13 AM, Bruno Marchal wrote: I am not convinced, as I tend to not believe in any primitive time and space, at least when I tend to believe in comp (of course I *know* nothing). QM is indeed reversible (in large part), but using this to select one branch by boundary condition, is still like a form of cosmic solipsism to me. We can't refute it, and unlike most QM collapse theories, we can't criticize it from locality and determinacy, but that does not yet make it convincing compare to MW, and infinitely more so in the comp frame, where we can't avoid the many dreams. It's just information from the future - which is exactly the same thing as true randomness, and both are operationally the same as FPI. That's why I think an advancement in QM interpretation would be to derive probability. Comp provides an explanation of randomness, but it's not clear to me that it implies a complex Hilbert space. 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/groups/opt_out.
Re: What are wavefunctions?
On 16 January 2014 01:13, Bruno Marchal marc...@ulb.ac.be wrote: On 15 Jan 2014, at 11:10, LizR wrote: On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. The setting of the analyser must be predetermined. And not in the mechanist sense, where the choice of the analyser is still made by you, even if deterministically so. With only one branch, you are not just using irreversibility, but you are using the boundary condition selecting a branch among all in the universal wave. You mean the measuring devices? If so, of course they are predetermined - as is the state of the emitter. Time symmetric physics would guarantee that. I don't see that is special, however. (But I will read on :) These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Those are still many-world theories, + some ugly selection principle to get one branch. It is very not natural, as you have quasi microsuperposition (appearance of many branches), but the macro-one are eliminated by ad hoc boundary conditions, which will differ depending on where you will decide to introduce the Heisenberg cut. Also, QM will prevent us to know or measure those boundary conditions, which makes them into (local, perhaps, in *some* sense) hidden variable theory. I don't understand the above. The theory is simply QM with no collapse and with no preferred time direction (it assumes any system which violates Bell's inequality has to operate below the level where decoherence brings in the effects of the entropy gradient). It is both local and realistic, since time symmetry is Bell's 4th assumption - it allows EPR experiments to be local and realistic (I am relying on John Bell for this information, I wouldn't be able to work it out myself). So it definitely is a hidden variable theory. Yes, and I am willing to accept it is local. but it is hyper-determined. It means that if I chose the setting of the two analyser in the Aspect experience by looking at my horoscope, that horoscope was determined by the whole future of the phsyical universe. Logically possible, you are right, but ugly, as it is a selection principle based on boundary conditions. It is more local than Bohm, and it does not need a new potential, but it is sill using abnormal special data for the TOE. It is no more a nice and gentle equation like the SWE, but that same equation together with tuns of mega-terra-gigabyte of data. I don't follow the whole future business. I'm only talking about what might be called micro-symmetry - symmetry below the level of coarse-graining at which entropic processes emerge. This is particularly not a problem in a block universe, or block multiverse, where there is no moving arrow of time and the outcomes are already there (maybe in multiple branches in the MWI). Where / why is all that extra data required? I think for it to work the system is kept from undergoing decoherence or any interaction that would lead to MWI branching. EPR experiments only appear to work for systems that are shielded from such effects, I think? So there isn't a problem with the MWI - the whole thing takes place in one branch, with no quantum interfence etc being relevant. (I believe that EPR experiments lose their ability to violate Bell's inequality once interactions occur that could cause MWI branching within the system under consideration???) ? I may be wrong on this, but I believe EPR experiments require that the particles being measured are isolated from decoherence - and hence from branching, in the MWI. So the MWI can be ignored for the purposes of analysing the experiment. Any proposed explanation for violations of Bell's inequality, therefore, should take into account what is logically possible if time is directionally neutral at the level of the particles being measured. LATER NOTE - see below for me revising my ideas on this! Many worlds is far less ad-hoc, imo. There is no Heisenberg cut, and the boundary conditions does not play any special role, and indeed they are all realized in the universal wave (and in arithmetic). Please explain about
Re: What are wavefunctions?
On 16 January 2014 03:51, Jesse Mazer laserma...@gmail.com wrote: On Wed, Jan 15, 2014 at 5:10 AM, LizR lizj...@gmail.com wrote: On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Time symmetry in the laws of physics alone, without any special restriction on boundary conditions, can't get you violation of Bell inequalities. Ordinary time symmetry doesn't mean you have to take into account both future and past to determine what happens in a given region of spacetime after all, it just means you can deduce it equally well going in *either* direction. So in a deterministic time-symmetric theory (Price's speculations about hidden variables are at least compatible with determinism) it's still true that what happens in any region of spacetime can be determined entirely by events in its past light cone, say the ones occurring at some arbitrarily-chosen initial tim. This means that in a Price-like theory where measurement results are explained in terms of hidden variables the particles carry with them from emitter to experimenters, it must be true that the original assignment of the hidden variables to each particle at the emitter is determined by the past light cone of the event of each particle leaving the emitter. Meanwhile, the event of an experimenter choosing which measurement to perform will have its own past light cone, and there are plenty of events in the past light cone of the choice that do *not* lie in the past light cone of the particles leaving the emitter. So, without any restriction on boundary conditions, one can choose an ensemble of possible initial conditions with the following properties: 1. The initial states of all points in space that line in the past light cone of the particles leaving the emitter are identical for each member of the ensemble, so in every possible history generated from these initial conditions, the particles have the same hidden variables associated with them. 2. The initial states of points in space that lie in the past light cone of the experimenters choosing what spin direction to measure vary in different members of the ensemble, in such a way that all combinations of measurement choices are represented in different histories chosen from this ensemble. If both these conditions apply, Bell's proofs that various inequalities shouldn't be violated works just fine--for example, there's no combination of hidden variables you can choose for the particle pair that ensure that in all the histories where the experimenters measure along the *same* axis they get opposite results (spin-up for one experimenter, spin-down for the other) with probability 1, but in all the histories where they measure along two *different* axes they have less than a 1/3 chance of getting opposite results. Only by having the hidden variables assigned during emission be statistically correlated to the choices the experimenters later make about measurements can Price's argument work, and the argument above shows that time-symmetry without special boundary conditions won't suffice for this. If you're right then Price is wrong. However I don't recall him saying that the only consequence of time symmetry is that events can be, so to speak, worked backwards equally well. In particular, I read his EPR explanation as showing that both future and past boundary conditions were relevant in explaining the violations of B's Inequality. The forwards-and-backwards version would prevent time symmetry having any detectable effects, as far as I can see. (Also I'd like to see an explanation of EPR which works backwards from the measurement settings to the emitter and explains the violation of B's Inequality. That would definitely be a clincher!) -- 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
Re: What are wavefunctions?
On 1/15/2014 4:03 PM, LizR wrote: By the way, I may have this wrong but it seems to me your hyperdeterminism objection is an objection to block universes generally. I can't see how the big crunch (or timelike infinity) being a boundary condition on the universe is a problem in a block universe (or multiverse) ...? I think Bruno is thinking of a tree-like branching block multiverse so there can still be FPI due to the branches. Otherwise definite, random things have to happen in realizing the block universe - and Bruno hates random things and he likes infinities, so... But you should read L.S. Schulman's solution to the problem of randomness. He speculates that within the domain of a state we can prepare, which is of measure hbar=/=0, there are special states which are causally connected to *future* states and when we choose a measurement in the future we are selecting out one of these special states. 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/groups/opt_out.
Re: What are wavefunctions?
On 16 January 2014 13:57, meekerdb meeke...@verizon.net wrote: On 1/15/2014 4:03 PM, LizR wrote: By the way, I may have this wrong but it seems to me your hyperdeterminism objection is an objection to block universes generally. I can't see how the big crunch (or timelike infinity) being a boundary condition on the universe is a problem in a block universe (or multiverse) ...? I think Bruno is thinking of a tree-like branching block multiverse so there can still be FPI due to the branches. Otherwise definite, random things have to happen in realizing the block universe - and Bruno hates random things and he likes infinities, so... But you should read L.S. Schulman's solution to the problem of randomness. He speculates that within the domain of a state we can prepare, which is of measure hbar=/=0, there are special states which are causally connected to *future* states and when we choose a measurement in the future we are selecting out one of these special states. I am thinking of a block multiverse, too, and I can't see why future (or past) boundary conditions are a problem. Maybe I'm being thick, it wouldn't be the first time. Do you have a link to that reference? -- 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: What are wavefunctions?
Hyper determinism makes little sense as a serious theory to me. Why should particle properties conform to what a computer's random number generator outputs, and then the digits of Pi, and then the binary expansion of the square root of 2, all variously as the experimenters change the knobs as to what determines the spin axis of the lepton their analyzer measures. Are radioactive decays of particles really such things that are governed by the behavior of a selected random source, or alternately, are they really such things that govern what the digits of Pi or the square root of 2 are? Jason On Wed, Jan 15, 2014 at 6:13 AM, Bruno Marchal marc...@ulb.ac.be wrote: On 15 Jan 2014, at 11:10, LizR wrote: On 15 January 2014 22:55, Bruno Marchal marc...@ulb.ac.be wrote: On 14 Jan 2014, at 22:04, LizR wrote: Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? Logically, yes. But you need hyper-determinism, that is you need to select very special boundary conditions, which makes Cramer's transaction theory close to Bohm's theory. I'm not sure what you mean by special boundary conditions. The bcs in an Aspect type experiment are the device which creates the photons, and the settings of the measuring apparatuses. The setting of the analyser must be predetermined. And not in the mechanist sense, where the choice of the analyser is still made by you, even if deterministically so. With only one branch, you are not just using irreversibility, but you are using the boundary condition selecting a branch among all in the universal wave. These are special but only in that the photons are entangled ... note that this isn't Cramer's or Bohm's theory (the transaction theory requires far more complexity that this). Those are still many-world theories, + some ugly selection principle to get one branch. It is very not natural, as you have quasi microsuperposition (appearance of many branches), but the macro-one are eliminated by ad hoc boundary conditions, which will differ depending on where you will decide to introduce the Heisenberg cut. Also, QM will prevent us to know or measure those boundary conditions, which makes them into (local, perhaps, in *some* sense) hidden variable theory. I don't understand the above. The theory is simply QM with no collapse and with no preferred time direction (it assumes any system which violates Bell's inequality has to operate below the level where decoherence brings in the effects of the entropy gradient). It is both local and realistic, since time symmetry is Bell's 4th assumption - it allows EPR experiments to be local and realistic (I am relying on John Bell for this information, I wouldn't be able to work it out myself). So it definitely is a hidden variable theory. Yes, and I am willing to accept it is local. but it is hyper-determined. It means that if I chose the setting of the two analyser in the Aspect experience by looking at my horoscope, that horoscope was determined by the whole future of the phsyical universe. Logically possible, you are right, but ugly, as it is a selection principle based on boundary conditions. It is more local than Bohm, and it does not need a new potential, but it is sill using abnormal special data for the TOE. It is no more a nice and gentle equation like the SWE, but that same equation together with tuns of mega-terra-gigabyte of data. I think for it to work the system is kept from undergoing decoherence or any interaction that would lead to MWI branching. EPR experiments only appear to work for systems that are shielded from such effects, I think? So there isn't a problem with the MWI - the whole thing takes place in one branch, with no quantum interfence etc being relevant. (I believe that EPR experiments lose their ability to violate Bell's inequality once interactions occur that could cause MWI branching within the system under consideration???) ? Many worlds is far less ad-hoc, imo. There is no Heisenberg cut, and the boundary conditions does not play any special role, and indeed they are all realized in the universal wave (and in arithmetic). Please explain about the Heisenberg cut. I've heard the term, but don't know how it relates to EPR experiments. The Heinsenberg cut is where the wave should collapse in the Copenhagen QM. Von Neumann understood well that it is largely arbitrary. In all one world theory, you have to justify why the superposition works so well for the micro-worlds, and disappear for the macro-world. Using reversiblity, cannot by itself solve that problem. What works is reversibility and the boundaries conditions. God needs to know all the detail of
Re: What are wavefunctions?
On 16 January 2014 14:11, meekerdb meeke...@verizon.net wrote: You can do that (in fact it may have been done). You have two emitters with polarizers and a detector at which you post-select only those particles that arrive and form a singlet. Then you will find that the correlation counts for that subset violates Bell's inequality for polarizer settings of 30, 60, 120deg. I assume that means Price's (and Bell's) assumption that violations of Bell's inequality can be explained locally and realistically with time symmetry is definitely wrong...? -- 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: What are wavefunctions?
On 1/15/2014 5:13 PM, LizR wrote: On 16 January 2014 13:57, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: On 1/15/2014 4:03 PM, LizR wrote: By the way, I may have this wrong but it seems to me your hyperdeterminism objection is an objection to block universes generally. I can't see how the big crunch (or timelike infinity) being a boundary condition on the universe is a problem in a block universe (or multiverse) ...? I think Bruno is thinking of a tree-like branching block multiverse so there can still be FPI due to the branches. Otherwise definite, random things have to happen in realizing the block universe - and Bruno hates random things and he likes infinities, so... But you should read L.S. Schulman's solution to the problem of randomness. He speculates that within the domain of a state we can prepare, which is of measure hbar=/=0, there are special states which are causally connected to *future* states and when we choose a measurement in the future we are selecting out one of these special states. I am thinking of a block multiverse, too, and I can't see why future (or past) boundary conditions are a problem. Maybe I'm being thick, it wouldn't be the first time. Do you have a link to that reference? His book Schulman L S 1997 Time's Arrows and Quantum Measurement (New York: Cambridge University Press) also http://arxiv.org/pdf/1310.2602.pdf 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/groups/opt_out.
Re: What are wavefunctions?
Thanks. I probably haven't time for the book, but will try to understand the paper. On 16 January 2014 16:47, meekerdb meeke...@verizon.net wrote: On 1/15/2014 5:13 PM, LizR wrote: On 16 January 2014 13:57, meekerdb meeke...@verizon.net wrote: On 1/15/2014 4:03 PM, LizR wrote: By the way, I may have this wrong but it seems to me your hyperdeterminism objection is an objection to block universes generally. I can't see how the big crunch (or timelike infinity) being a boundary condition on the universe is a problem in a block universe (or multiverse) ...? I think Bruno is thinking of a tree-like branching block multiverseso there can still be FPI due to the branches. Otherwise definite, random things have to happen in realizing the block universe - and Bruno hates random things and he likes infinities, so... But you should read L.S. Schulman's solution to the problem of randomness. He speculates that within the domain of a state we can prepare, which is of measure hbar=/=0, there are special states which are causally connected to *future* states and when we choose a measurement in the future we are selecting out one of these special states. I am thinking of a block multiverse, too, and I can't see why future (or past) boundary conditions are a problem. Maybe I'm being thick, it wouldn't be the first time. Do you have a link to that reference? His book Schulman L S 1997 Time’s Arrows and Quantum Measurement (New York: Cambridge University Press) also http://arxiv.org/pdf/1310.2602.pdf 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/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: What are wavefunctions?
On 1/15/2014 7:05 PM, Jason Resch wrote: Hyper determinism makes little sense as a serious theory to me. Why should particle properties conform to what a computer's random number generator outputs, and then the digits of Pi, and then the binary expansion of the square root of 2, all variously as the experimenters change the knobs as to what determines the spin axis of the lepton their analyzer measures. Are radioactive decays of particles really such things that are governed by the behavior of a selected random source, or alternately, are they really such things that govern what the digits of Pi or the square root of 2 are? They are all part of the same reality. You assume its the experimental choice of measurement that determines the particles response, but I think the picture is supposed to be that both the particle in the experiment and the particles making up the experimenter are determined by the same laws. 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/groups/opt_out.
Re: What are wavefunctions?
On 1/15/2014 7:08 PM, LizR wrote: On 16 January 2014 14:11, meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: You can do that (in fact it may have been done). You have two emitters with polarizers and a detector at which you post-select only those particles that arrive and form a singlet. Then you will find that the correlation counts for that subset violates Bell's inequality for polarizer settings of 30, 60, 120deg. I assume that means Price's (and Bell's) assumption that violations of Bell's inequality can be explained locally and realistically with time symmetry is definitely wrong...? ?? Why do you conclude that? It's the time-reverse of the EPR that violated BI. 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/groups/opt_out.
Re: What are wavefunctions?
On Thu, Jan 16, 2014 at 12:58 AM, meekerdb meeke...@verizon.net wrote: On 1/15/2014 7:05 PM, Jason Resch wrote: Hyper determinism makes little sense as a serious theory to me. Why should particle properties conform to what a computer's random number generator outputs, and then the digits of Pi, and then the binary expansion of the square root of 2, all variously as the experimenters change the knobs as to what determines the spin axis of the lepton their analyzer measures. Are radioactive decays of particles really such things that are governed by the behavior of a selected random source, or alternately, are they really such things that govern what the digits of Pi or the square root of 2 are? They are all part of the same reality. Are they? Aren't numbers like Pi and sqrt(2) beyond the reality of QM, or rather, more fundamental than it? The moment you admit numbers like Pi into your reality, you get much more than just QM. You assume its the experimental choice of measurement that determines the particles response, but I think the picture is supposed to be that both the particle in the experiment and the particles making up the experimenter are determined by the same laws. So how, when using the digits of Pi to decide whether to measure the x-axis, or the y-axis, does the particle (when it decays), know to have both electron and positron agree measured on some axis, when that axis is determined by some relation between a circle and its diameter? Here the laws involved seemed to go beyond physical laws, it introduces mathematical laws, which can selectively be made to control/guide physics.. Jason -- 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: What are wavefunctions?
On Sun, Jan 12, 2014 at 1:22 PM, Jesse Mazer laserma...@gmail.com wrote: We know better than to think classical physics represents an exact description of our universe, but it certainly describes a logically possible mathematical universe Maybe but we don't know that with certainty, if we ever find a Theory of Everything we might find that classical physics is logically self contradictory. if you believe in some hidden-variable theory, ANY hidden-variable theory, then you know that if things are realistic AND local then Bell's inequality can NEVER be violated; and that would be true in every corner of the multiverse provided that basic logic and arithmetic is as true there as here. But experiment has shown unequivocally that Bell's inequality IS violated. So you tell me, what conclusions can a logical person can draw from that? It tells us that either we must use a nonlocal hidden variables interpretation like Bohmian mechanics Yes, things might be nonlocal. or that hidden variables are wrong. Yes, things might not be realistic. And things might not be local or realistic. Did you understand that in the sentence above that you quoted, I was saying that there is nothing in principle preventing you from determining an exact quantum state for a system You can know the exact quantum state for a system, that is to say you can know the exact wave function BUT that deals in nothing observable like position or momentum; you must square that complex function for that and even then it only gives you a probability not a exactitude. And it's even worse than that because it is a complex function so two very different functions ( F(x)=2 and F(x) = -2 for a trivial example) can produce the same number when squared, and thus the same probability. You said it yourself, the rules of the Game of Life are NOT reversible, that means there is more than one way for something to get into a given state. And the present entropy of a system is defined by Boltzman as the logarithm of the number of ways the system could have gotten into the state it's in now, therefore every application of one of the fundamental rules of physics in the Game of Life universe can only increase entropy. You are failing to specify whether you mean state to refer to microstate or macrostate and thus speaking ambiguously. Oh for heaven's sake, one of the great beauties of the Game of Life is that the meaning of state is simple and crystal clear; although in that game I don't know the dividing line between microstates and macrostates so I just call them states. even with reversible laws there is more than one way to get into a given macrostate No. If there are 2 different states of the universe that could have produced things as they are now then there is no way to decide between them and history is unknowable (just as it is in the Game of Life) and the laws of physics are not reversible. The entropy is defined not in terms of some vague notion of the number of ways the system could have gotten into its present microstate, You mean its present macrostate. And I see nothing vague about it. but rather as the number of possible microstates the system might be in at this moment given that we only know the macrostate We don't even know for a fact that some macroscopic objects, like Black Holes for example, even contain microstates; in fact the present thinking (a minority disagrees) is that probably they don't and a Black Hole can be completely described by just 3 numbers, its mass, spin, and electric charge. A Black Hole contains enormous entropy because there are a gargantuan number of ways it could have been formed, but if you know those 3 numbers then you know all there is to know about a particular Black Hole. And in the real world only 2 numbers are important because the electric charge is always zero. For example, suppose we consider a very small 2x2 board with only 4 cells [...] What are the laws of physics in this new game? A 2x2 board is MUCH too small for the traditional rules of the Game of Life to be applicable. And if the macrostate is 0 black:4 white there's only one possible microstate (same for 4 black:0 white), so this is the lowest possible entropy I don't know about this new game of yours because I don't know what the rules are but in the Game of Life a solid block of nothing but active cells would be in the lowest possible entropy state because the fewest previous states could have produced it. Actually I should have said the lowest impossible entropy state because NO previous state could have produced it, zero. A solid block of nothing but dead cells would have the highest entropy because more previous states than any other could have produced it, and entropy is the logarithm of the number of those states. If it starts out in a macrostate of maximum entropy [...] Then nothing the laws of physics do to it can increase it's entropy regardless of what those laws
Re: What are wavefunctions?
On Sun, Jan 12, 2014 at 6:41 PM, LizR lizj...@gmail.com wrote: Retro-causality (time symmetry is a better term) only exists at the quantum level. Why? Where is the dividing line? And with a Schrodinger's Cat type device a quantum event can easily be magnified to a macro-event as large as desired, you could connect it up to an H-bomb. The dividing line appears to be roughly where decoherence occurs. Basically anything above a single quantum entity engaged in a carefully controlled interaction is liable to get its time symmetric properties washed out by interactions with other particles The nucleus of an atom is tiny even by atomic standards so it is certainly at the quantum level, and in its natural state of existing inside a huge chunk of irregular gyrating matter this tiny thing is constantly subject to the slings and arrows of outrageous fortune from an astronomical number of other clumsy atoms; and yet the half life of Bismuth 209 is 1.9 * 10^19 years. Why? It's just a fact, if time were symmetrical then you'd be just as good at predicting the future as you are at remembering the past, so you'd know the outcome of an experiment before you performed it just as well as you remember setting up the apparatus. But this is not the way things are because the second law exists. And the second law exists because of low entropy initial conditions. And I don't know why there were low entropy initial conditions. OK. So the above statement of yours about predicting the future is still false, Yes it's false, I don't think this will come as a great news flash but the truth is we're not as good at predicting the future as we are at remembering the past. And the reason we're not is that time is not symmetrical. To recap briefly -- the laws of physics are time symmetrical, Yes, the fundamental laws of physics, the ones we know anyway, seem to be time symmetrical. But that doesn't mean that time is symmetrical. and most particle interactions are constrained by boundary conditions. Yes, and that is why time is NOT symmetrical. 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/groups/opt_out.
Re: What are wavefunctions?
On 1/14/2014 8:33 AM, John Clark wrote: but rather as the number of possible microstates the system might be in at this moment given that we only know the macrostate We don't even know for a fact that some macroscopic objects, like Black Holes for example, even contain microstates; in fact the present thinking (a minority disagrees) is that probably they don't and a Black Hole can be completely described by just 3 numbers, its mass, spin, and electric charge. A Black Hole contains enormous entropy because there are a gargantuan number of ways it could have been formed, but if you know those 3 numbers then you know all there is to know about a particular Black Hole. And in the real world only 2 numbers are important because the electric charge is always zero. For example, suppose we consider a very small 2x2 board with only 4 cells [...] What are the laws of physics in this new game? A 2x2 board is MUCH too small for the traditional rules of the Game of Life to be applicable. And if the macrostate is 0 black:4 white there's only one possible microstate (same for 4 black:0 white), so this is the lowest possible entropy I don't know about this new game of yours because I don't know what the rules are but in the Game of Life a solid block of nothing but active cells would be in the lowest possible entropy state because the fewest previous states could have produced it. Actually I should have said the lowest impossible entropy state because NO previous state could have produced it, zero. A solid block of nothing but dead cells would have the highest entropy because more previous states than any other could have produced it, and entropy is the logarithm of the number of those states. You seem to have a non-standard view of entropy in statistical mechanics. It is NOT the log of the number of ways a macro-state could form. That would be ambiguous in any case (do different order of events count as different ways?...different paths to the events?). The entropy is the log of the number of micro-states consistent with the macro-state. A black hole has entropy because it has a temperature, which implies that it has micro-states. And the relationship between energy and temperature implies that the number of micro-states is the event horizon area measured in Planck units. To say it only has mass, charge, and angular momentum is just to give a classical macro-state description, like saying gas in a vessel just has pressure, temperature, and volume. 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/groups/opt_out.
Re: What are wavefunctions?
On 15 January 2014 05:33, John Clark johnkcl...@gmail.com wrote: On Sun, Jan 12, 2014 at 1:22 PM, Jesse Mazer laserma...@gmail.com wrote: We know better than to think classical physics represents an exact description of our universe, but it certainly describes a logically possible mathematical universe Maybe but we don't know that with certainty, if we ever find a Theory of Everything we might find that classical physics is logically self contradictory. We already know that it may contain singularities, which could be considered at least physically problematical if not downright logically inconsistent (especially by people who don't think anything real can be infinite). Of course GR fails on that basis 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/groups/opt_out.
Re: What are wavefunctions?
On 15 January 2014 06:11, John Clark johnkcl...@gmail.com wrote: On Sun, Jan 12, 2014 at 6:41 PM, LizR lizj...@gmail.com wrote: Retro-causality (time symmetry is a better term) only exists at the quantum level. Why? Where is the dividing line? And with a Schrodinger's Cat type device a quantum event can easily be magnified to a macro-event as large as desired, you could connect it up to an H-bomb. The dividing line appears to be roughly where decoherence occurs. Basically anything above a single quantum entity engaged in a carefully controlled interaction is liable to get its time symmetric properties washed out by interactions with other particles The nucleus of an atom is tiny even by atomic standards so it is certainly at the quantum level, and in its natural state of existing inside a huge chunk of irregular gyrating matter this tiny thing is constantly subject to the slings and arrows of outrageous fortune from an astronomical number of other clumsy atoms; and yet the half life of Bismuth 209 is 1.9 * 10^19 years. Why? Because that's how long it takes for the relevant particles to get over the potential barrier. But this is irrelevant. Atomic nuclei are (probably) already on the wrong side of the entropy fence in any case. They're bound states which can only occur under certain special cirumstances, namely when the universe expands and cools enough to allow them to form. And atomic nuclei haven't been used to violate Bell's inequality as far as I know. It's just a fact, if time were symmetrical then you'd be just as good at predicting the future as you are at remembering the past, so you'd know the outcome of an experiment before you performed it just as well as you remember setting up the apparatus. But this is not the way things are because the second law exists. And the second law exists because of low entropy initial conditions. And I don't know why there were low entropy initial conditions. OK. So the above statement of yours about predicting the future is still false, Yes it's false, I don't think this will come as a great news flash but the truth is we're not as good at predicting the future as we are at remembering the past. And the reason we're not is that time is not symmetrical. Except below the level of coarse graining at which entropy operates, that is correct. And I never claimed otherwise. As I keep saying, I'm only claiming this is relevant in special circumstances like EPR experiments. To recap briefly -- the laws of physics are time symmetrical, Yes, the fundamental laws of physics, the ones we know anyway, seem to be time symmetrical. But that doesn't mean that time is symmetrical. ...is just words. Stop nitpicking. If the laws of physics are time symmetrical, that has a potential influence on EPR experiments. and most particle interactions are constrained by boundary conditions. Yes, and that is why time is NOT symmetrical. Stop playing with words. The time symmetry of fundamental physics is there, so it's perfectly valid to say time is symmetrical below the level of coarse graining needed to derive the 2nd law, and asymmetrical above it. (That's virtually a simple restatement of Boltzmann's H-theorem for dummies.) The point is that symmetrical time may become apparent in EPR setups. You haven't yet given even a suggestion of a reason why it wouldn't, just a load of hand waving about stuff that is IRRELEVANT to EPR experiments, which are carefully prepared to avoid all the influences you've mentioned. Now how about discussing what I've actually claimed, that time symmetry of physics could account for the special situation which has to be created to obtain EPR results? -- 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: What are wavefunctions?
Sorry, I realise that last sentence could be misconstrued by someone who's being very nitpicky and looking for irrelevant loopholes to argue about, so let's try again. Now how about discussing what I've actually claimed, that the time symmetry of fundamental physics could account for the results obtained in EPR experiments? On 15 January 2014 10:01, LizR lizj...@gmail.com wrote: On 15 January 2014 06:11, John Clark johnkcl...@gmail.com wrote: On Sun, Jan 12, 2014 at 6:41 PM, LizR lizj...@gmail.com wrote: Retro-causality (time symmetry is a better term) only exists at the quantum level. Why? Where is the dividing line? And with a Schrodinger's Cat type device a quantum event can easily be magnified to a macro-event as large as desired, you could connect it up to an H-bomb. The dividing line appears to be roughly where decoherence occurs. Basically anything above a single quantum entity engaged in a carefully controlled interaction is liable to get its time symmetric properties washed out by interactions with other particles The nucleus of an atom is tiny even by atomic standards so it is certainly at the quantum level, and in its natural state of existing inside a huge chunk of irregular gyrating matter this tiny thing is constantly subject to the slings and arrows of outrageous fortune from an astronomical number of other clumsy atoms; and yet the half life of Bismuth 209 is 1.9 * 10^19 years. Why? Because that's how long it takes for the relevant particles to get over the potential barrier. But this is irrelevant. Atomic nuclei are (probably) already on the wrong side of the entropy fence in any case. They're bound states which can only occur under certain special cirumstances, namely when the universe expands and cools enough to allow them to form. And atomic nuclei haven't been used to violate Bell's inequality as far as I know. It's just a fact, if time were symmetrical then you'd be just as good at predicting the future as you are at remembering the past, so you'd know the outcome of an experiment before you performed it just as well as you remember setting up the apparatus. But this is not the way things are because the second law exists. And the second law exists because of low entropy initial conditions. And I don't know why there were low entropy initial conditions. OK. So the above statement of yours about predicting the future is still false, Yes it's false, I don't think this will come as a great news flash but the truth is we're not as good at predicting the future as we are at remembering the past. And the reason we're not is that time is not symmetrical. Except below the level of coarse graining at which entropy operates, that is correct. And I never claimed otherwise. As I keep saying, I'm only claiming this is relevant in special circumstances like EPR experiments. To recap briefly -- the laws of physics are time symmetrical, Yes, the fundamental laws of physics, the ones we know anyway, seem to be time symmetrical. But that doesn't mean that time is symmetrical. ...is just words. Stop nitpicking. If the laws of physics are time symmetrical, that has a potential influence on EPR experiments. and most particle interactions are constrained by boundary conditions. Yes, and that is why time is NOT symmetrical. Stop playing with words. The time symmetry of fundamental physics is there, so it's perfectly valid to say time is symmetrical below the level of coarse graining needed to derive the 2nd law, and asymmetrical above it. (That's virtually a simple restatement of Boltzmann's H-theorem for dummies.) The point is that symmetrical time may become apparent in EPR setups. You haven't yet given even a suggestion of a reason why it wouldn't, just a load of hand waving about stuff that is IRRELEVANT to EPR experiments, which are carefully prepared to avoid all the influences you've mentioned. Now how about discussing what I've actually claimed, that time symmetry of physics could account for the special situation which has to be created to obtain EPR results? -- 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: What are wavefunctions?
On Fri, Jan 10, 2014 at 2:23 PM, Jesse Mazer laserma...@gmail.com wrot In classical physics there is no limit in principle to your knowledge of the microstate. Yes, 150 years ago every physicist alive thought that, today we know better. And in quantum physics, there is nothing in principle preventing you from determining an exact quantum state for a system; only if you believe in some hidden-variables theory And if you believe in some hidden-variable theory, ANY hidden-variable theory, then you know that if things are realistic AND local then Bell's inequality can NEVER be violated; and that would be true in every corner of the multiverse provided that basic logic and arithmetic is as true there as here. But experiment has shown unequivocally that Bell's inequality IS violated. So you tell me, what conclusions can a logical person can draw from that? like a theory that says that particles have precise position and momentum at all times, even though you can't measure them both simultaneously If things have properties, like position and momentum, even if they are not observed and even if they can't be observed in principle, then that would be a realistic theory. If such a theory was also local you would know it is wrong, that is to say it would conflict with the observed facts. Do you think my Toroidal Game of Life (a finite grid of cells with the edges identified, giving it the topology of a torus) is a mathematically well-defined possible universe? Yes. Do you disagree that starting from a randomly-chosen initial state which is likely to have something close to a 50:50 ratio of black to white squares, the board is likely to evolve to a state dominated by white squares, which would have lower entropy if we define macrostates in terms of the black:white ratio? You said it yourself, the rules of the Game of Life are NOT reversible, that means there is more than one way for something to get into a given state. And the present entropy of a system is defined by Boltzman as the logarithm of the number of ways the system could have gotten into the state it's in now, therefore every application of one of the fundamental rules of physics in the Game of Life universe can only increase entropy. The 2nd law is not restricted to initial conditions of very low entropy, it says that if the entropy is anything lower than the maximum it will statistically tend to increase, and if the entropy is at the maximum it is statistically more likely to stay at that value than to drop to any specific lower value. If the universe started out in a state of maximum entropy then any change in it, that is to say any application of one of the fundamental laws of physics will with certainty DECREASE that entropy. And If the universe started out in a state of ALMOST maximum entropy then any application of one of the fundamental laws of physics will PROBABLY decrease that entropy. If the initial conditions deviated from maximum entropy even slightly, the second law says that an increase in entropy should be more likely than a decrease. That would depend on initial conditions, just how slight the slight deviation from maximum entropy was. Well... you can make a Turing Machine from the Game of Life. And according to the Bekenstein Bound The Bekenstein Bound is itself just a property of the particular laws of physics in our universe, This must be one of the few places where people talk about things that just apply to our universe. no one claims it would apply to all logically possible mathematical universes, so how is it relevant to this discussion about whether the 2nd law would apply to all such possible universes? That wasn't what I was responding to. You said: since even though it's possible our universe could be a cellular automaton, I think we can be pretty confident it's not a 2-dimensional cellular automaton like the Game of Life! And I gave reasons why I am not pretty confident So the rules of the Game of Life apply to some of the cells in the grid but do not apply to others. What rules govern which cells must obey the rules and which cells can ignore the rules, that is to say who is allowed to ignore the laws of physics in that universe? No, they apply to all squares in the ideal platonic infinite board whose behavior you want to deduce, Then ratios become meaningless. but there is no need to actually *simulate* any of the squares outside the region containing black squares, because you know by the rules governing the ideal platonic infinite board that those squares will stay all-white as long as long as they are not neighbors with any black square I think you've got your colors backward because a solid block of active cells does not stay a solid block. But never mind the point is that the pattern of active cells is constantly expanding and shrinking in a unpredictable way (that is to say the only way to know what it will do is
Re: What are wavefunctions?
On Fri, Jan 10, 2014 at 4:47 PM, LizR lizj...@gmail.com wrote: Retro-causality (time symmetry is a better term) only exists at the quantum level. Why? Where is the dividing line? And with a Schrodinger's Cat type device a quantum event can easily be magnified to a macro-event as large as desired, you could connect it up to an H-bomb. The laws of physics are time-symmetric, but constrained by boundary conditions. And that is exactly what I've been saying over and over, and that is why the second law is almost always true and that is why time has a direction. There is a very influential boundary condition in what we call the past, namely the Big Bang, plus less influential ones in the future, Exactly. And by the way, if time is symmetrical then there is no point in ever actually performing an experiment because you would remember the future as clearly as you remember the past, so you would already remember the outcome of the experiment just as clearly as you remember setting up the experimental apparatus. I assume you're not so stupid as to think that's what I've been claiming, so I can only assume this is a deliberate attempt at mockery, Yes sometimes I mock people but I promise you that was not my aim this time. It's just a fact, if time were symmetrical then you'd be just as good at predicting the future as you are at remembering the past, so you'd know the outcome of an experiment before you performed it just as well as you remember setting up the apparatus. But this is not the way things are because the second law exists. And the second law exists because of low entropy initial conditions. And I don't know why there were low entropy initial conditions. 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/groups/opt_out.
Re: What are wavefunctions?
On 12 Jan 2014, at 16:53, John Clark wrote: On Fri, Jan 10, 2014 at 2:23 PM, Jesse Mazer laserma...@gmail.com wrot In classical physics there is no limit in principle to your knowledge of the microstate. Yes, 150 years ago every physicist alive thought that, today we know better. And in quantum physics, there is nothing in principle preventing you from determining an exact quantum state for a system; only if you believe in some hidden-variables theory And if you believe in some hidden-variable theory, ANY hidden- variable theory, then you know that if things are realistic AND local then Bell's inequality can NEVER be violated; and that would be true in every corner of the multiverse provided that basic logic and arithmetic is as true there as here. But experiment has shown unequivocally that Bell's inequality IS violated. You keep saying this, but that is incorrect. The experiments have just shown that the Bell's inequality are violated in our universe, assuming that the outcomes of our experiments are definite, which they are not in the multiverse. Those experiments show nothing about our multiverse. The experiment are supposed to give definite outcomes, not the never collapsing superposed entanglement described in the big picture of the multiverse. Read Deutsch and Hayden's paper, or Tipler's one, of just try to conceive an experimental set up showing a quantum violation of Bell's inequality in the many-world picture (if that can mean anything). Others gave links and papers. MW is realist on all outcomes. The wave never collapse, which already suggest no action at a distance, but when you do the math, like Tipler, or Deustch and Hayden, (using the FPI, though, but restricted to the quantum computations, like Everett), you can see that nothing non local ever occurs. Bell uses realism in some of his context, to say that there is only one (real) outcome, which is basically the contrary of the MW theory. Bruno So you tell me, what conclusions can a logical person can draw from that? like a theory that says that particles have precise position and momentum at all times, even though you can't measure them both simultaneously If things have properties, like position and momentum, even if they are not observed and even if they can't be observed in principle, then that would be a realistic theory. If such a theory was also local you would know it is wrong, that is to say it would conflict with the observed facts. Do you think my Toroidal Game of Life (a finite grid of cells with the edges identified, giving it the topology of a torus) is a mathematically well-defined possible universe? Yes. Do you disagree that starting from a randomly-chosen initial state which is likely to have something close to a 50:50 ratio of black to white squares, the board is likely to evolve to a state dominated by white squares, which would have lower entropy if we define macrostates in terms of the black:white ratio? You said it yourself, the rules of the Game of Life are NOT reversible, that means there is more than one way for something to get into a given state. And the present entropy of a system is defined by Boltzman as the logarithm of the number of ways the system could have gotten into the state it's in now, therefore every application of one of the fundamental rules of physics in the Game of Life universe can only increase entropy. The 2nd law is not restricted to initial conditions of very low entropy, it says that if the entropy is anything lower than the maximum it will statistically tend to increase, and if the entropy is at the maximum it is statistically more likely to stay at that value than to drop to any specific lower value. If the universe started out in a state of maximum entropy then any change in it, that is to say any application of one of the fundamental laws of physics will with certainty DECREASE that entropy. And If the universe started out in a state of ALMOST maximum entropy then any application of one of the fundamental laws of physics will PROBABLY decrease that entropy. If the initial conditions deviated from maximum entropy even slightly, the second law says that an increase in entropy should be more likely than a decrease. That would depend on initial conditions, just how slight the slight deviation from maximum entropy was. Well... you can make a Turing Machine from the Game of Life. And according to the Bekenstein Bound The Bekenstein Bound is itself just a property of the particular laws of physics in our universe, This must be one of the few places where people talk about things that just apply to our universe. no one claims it would apply to all logically possible mathematical universes, so how is it relevant to this discussion about whether the 2nd law would apply to all such possible universes? That wasn't what I
Re: What are wavefunctions?
On Fri, Jan 10, 2014 at 9:06 PM, meekerdb meeke...@verizon.net wrote: I'm not sure what time is symmetrical means to you. The term is self evident. It's the equations of dynamical evolution that are t-symmetric in physics Yes, time symmetrical laws of physics would usually mean that time was symmetrical too, but not under very unusual initial conditions, like a state of very low entropy. then retro-causality exists, so how can realism hold? How can the outcome of a coin flip today have a definite value independent of the observer if next year or next millennium someone can cause a change in today's coin flip? If the coin flip today had a definite outcome Then things would be realistic. why do suppose some one the future could simply choose it to be a different outcome? Because if time were symmetrical then retro-causality would be just as common as forward-causality and things would not be realistic. free will? Cannot comment, don't know what ASCII sequence free will means. So you think realism would have no meaning in Laplace's deterministic universe? Not at all, if things were deterministic then their values would exist regardless of if somebody was observing them, or even if he could. And by the way, if time is symmetrical then there is no point in ever actually performing an experiment because you would remember the future as clearly as you remember the past, so you would already remember the outcome of the experiment just as clearly as you remember setting up the experimental apparatus. Not if time is symmetrical No,*only* if time is symmetrical. dynamical equations are t-symmetric and memory depends on the state of a lot of particles in your brain so that the 2nd law applies. If the 2nd law applies then time is not symmetrical because it says that something (entropy) gets larger in one direction than it does in the other, and that is lopsided. 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/groups/opt_out.
Re: What are wavefunctions?
On Sun, Jan 12, 2014 at 10:53 AM, John Clark johnkcl...@gmail.com wrote: On Fri, Jan 10, 2014 at 2:23 PM, Jesse Mazer laserma...@gmail.com wrot In classical physics there is no limit in principle to your knowledge of the microstate. Yes, 150 years ago every physicist alive thought that, today we know better. We know better than to think classical physics represents an exact description of our universe, but it certainly describes a logically possible mathematical universe (note that in the previous paragraph of that message of mine you are replying to, I said Liouville's theorem would be precisely true in a possible universe where the laws of classical physics hold exactly...for reference, that message is at https://groups.google.com/d/msg/everything-list/hJ9bNWqoAzI/73DulLV7iyEJ ) And in quantum physics, there is nothing in principle preventing you from determining an exact quantum state for a system; only if you believe in some hidden-variables theory And if you believe in some hidden-variable theory, ANY hidden-variable theory, then you know that if things are realistic AND local then Bell's inequality can NEVER be violated; and that would be true in every corner of the multiverse provided that basic logic and arithmetic is as true there as here. But experiment has shown unequivocally that Bell's inequality IS violated. So you tell me, what conclusions can a logical person can draw from that? It tells us that either we must use a nonlocal hidden variables interpretation like Bohmian mechanics, or that hidden variables are wrong. Did you understand that in the sentence above that you quoted, I was saying that there is nothing in principle preventing you from determining an exact quantum state for a system in the case that the conjecture of hidden variables is FALSE, not in the case that it's true? If there are no hidden variables, then you can in principle perform an exhaustive measurement on a system that will give you its exact state vector in Hilbert space, putting it in a pure state rather than a mixed state. So, this contradicts your claim that the laws of physics insist that you will *always* be uncertain about the microstates--a pure quantum state *is* a microstate in quantum physics without hidden variables, a macrostate would be a mixed state. Do you disagree that starting from a randomly-chosen initial state which is likely to have something close to a 50:50 ratio of black to white squares, the board is likely to evolve to a state dominated by white squares, which would have lower entropy if we define macrostates in terms of the black:white ratio? You said it yourself, the rules of the Game of Life are NOT reversible, that means there is more than one way for something to get into a given state. And the present entropy of a system is defined by Boltzman as the logarithm of the number of ways the system could have gotten into the state it's in now, therefore every application of one of the fundamental rules of physics in the Game of Life universe can only increase entropy. You are failing to specify whether you mean state to refer to microstate or macrostate and thus speaking ambiguously. The fact that the rules of the Game of Life are not reversible means that there is more than one way for something to get into a given microstate (even with reversible laws there is more than one way to get into a given macrostate). The entropy is defined not in terms of some vague notion of the number of ways the system could have gotten into its present microstate, but rather as the number of possible microstates the system might be in at this moment given that we only know the macrostate it's in at this moment. If we define macrostates for the Toroidal Game of Life in terms of the ratio of black to white squares, then the entropy of a given macrostate has nothing to do with looking at the board's possible states in the past, it's just a question of looking at the number of possible precise patterns of black and white squares that the board might have on the *current* time-increment that would give it that ratio of black:white on the current time-increment. For example, suppose we consider a very small 2x2 board with only 4 cells, and I use 0s to represent white cells and 1s to represent black cells. Then if the current macrostate is 2 black:2 white, the number of possible microstates would be 6, shown below: 11 00 10 10 10 01 01 10 01 01 00 11 If the macrostate were 1 black:3 white there would be 4 possible microstates (and same for 3 black:1 white), so this macrostate has a lower entropy: 10 00 01 00 00 10 00 01 And if the macrostate is 0 black:4 white there's only one possible microstate (same for 4 black:0 white), so this is the lowest possible entropy for a macrostate: 00 00 It's not hard to see why this pattern would continue to hold for larger boards--macrostates with a ratio that's closer to 1:1 will have a higher entropy than
Re: What are wavefunctions?
On 1/12/2014 8:20 AM, John Clark wrote: On Fri, Jan 10, 2014 at 4:47 PM, LizR lizj...@gmail.com mailto:lizj...@gmail.com wrote: Retro-causality (time symmetry is a better term) only exists at the quantum level. Why? Where is the dividing line? And with a Schrodinger's Cat type device a quantum event can easily be magnified to a macro-event as large as desired, you could connect it up to an H-bomb. That's a good question. But I think it has a good answer. The quantum level really means isolated from the general entropy increase of the universe. The Bucky Ball Young's slit experiment exemplifies this. If the bucky balls are hot enough to radiate photons that will provide which way information, the interference pattern doesn't appear. In the t-symmetry model this means the paths don't interact with the rest of universe. If you tried to send a message back in time via the zig-zag path it would require an interaction between the wave-function and your macroscopic message forming and environmentally decohered instruments. 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/groups/opt_out.
Re: What are wavefunctions?
On Sun, Jan 12, 2014 at 1:22 PM, Jesse Mazer laserma...@gmail.com wrote: The entropy is defined not in terms of some vague notion of the number of ways the system could have gotten into its present microstate, but rather as the number of possible microstates the system might be in at this moment given that we only know the macrostate it's in at this moment. Minor correction, I meant to say that the entropy is defined in terms of the number of microstates associated with the given macrostate--it isn't defined as the number of microstates itself, but rather the logarithm of that number (times Boltzmann's constant, if we're talking physical entropy rather than informational). 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: What are wavefunctions?
On 13 January 2014 05:20, John Clark johnkcl...@gmail.com wrote: On Fri, Jan 10, 2014 at 4:47 PM, LizR lizj...@gmail.com wrote: Retro-causality (time symmetry is a better term) only exists at the quantum level. Why? Where is the dividing line? And with a Schrodinger's Cat type device a quantum event can easily be magnified to a macro-event as large as desired, you could connect it up to an H-bomb. The dividing line appears to be roughly where decoherence occurs. Basically anything above a single quantum entity engaged in a carefully controlled interaction is liable to get its time symmetric properties washed out by interactions with other particles. I'm not sure exactly where the dividing line is, but once you get above the scale of coarse-graining at which the entropy gradient becomes manifest, you are going to lose any easily measurable consequences of time symmetry. Only in carefully controlled situations (like EPR experiments) can we remove the effects of influences from the rest of the universe to a great enough extent that we can see time-symmetry operating in a detectable manner (to, for example, violate Bell's inequality, at least if Bell is to be believed). The laws of physics are time-symmetric, but constrained by boundary conditions. And that is exactly what I've been saying over and over, and that is why the second law is almost always true and that is why time has a direction. Yes, I've been saying this over and over, too. So we agree. The second law is almost always true, and only in special cases like EPR experiments can we easily see the effects of time symmetry -- even though we *know* most of the laws of physics are time-symmetric (insofar as we know anything, of course). There is a very influential boundary condition in what we call the past, namely the Big Bang, plus less influential ones in the future, Exactly. This is why it's so hard to get our heads around the consequences of time symmetry. And by the way, if time is symmetrical then there is no point in ever actually performing an experiment because you would remember the future as clearly as you remember the past, so you would already remember the outcome of the experiment just as clearly as you remember setting up the experimental apparatus. I assume you're not so stupid as to think that's what I've been claiming, so I can only assume this is a deliberate attempt at mockery, Yes sometimes I mock people but I promise you that was not my aim this time. It's just a fact, if time were symmetrical then you'd be just as good at predicting the future as you are at remembering the past, so you'd know the outcome of an experiment before you performed it just as well as you remember setting up the apparatus. But this is not the way things are because the second law exists. And the second law exists because of low entropy initial conditions. And I don't know why there were low entropy initial conditions. OK. So the above statement of yours about predicting the future is still false, and hopefully you now understand why. To recap briefly -- the laws of physics are time symmetrical, and most particle interactions are constrained by boundary conditions. Almost everything in the universe is constrained by the boundary condition of the Big Bang (+ cosmic expansion). This creates an entropy gradient (or rather what we perceive as one, as Brent explained the entropy of a system doesn't change at the quantum level, but we exist above the level of coarse graining at which the 2nd law emerges). This prevents us measuring the results of any future experiments that involve anything above the level of coarse-graining, i.e. above the level of a few carefully prepared particles. And since we don't use EPR type experiments for our memories, we can't remember the future. -- 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: What are wavefunctions?
On Thu, Jan 9, 2014 Jesse Mazer laserma...@gmail.com wrote: I never claimed Liouville's theorem was a fundamental law of physics in itself, Good, I agree. rather it is derivable as a mathematical consequence of certain features of the fundamental laws. And of the initial conditions! Liouville's theorem is derived in deterministic classical mechanics. Then Liouville's theorem can only be approximately true. It [Liouville's theorem] only becomes statistical if you interpret the original set of microstates as representing your own uncertainty But that's the only way you can interpret it because the laws of physics insist that you will *always* be uncertain about the microstates, all you know are purely statistical things about the system, like its temperature and pressure. This line of discussion got started because I was disputing your statement that we can derive the 2nd law in a *purely* logical way like 2+2=5, with no need to invoke knowledge about the laws of physics that was based on observation. This would imply that *any* logically possible mathematical laws of nature would obey the 2nd law. Yes, *any* logically possible mathematical law of nature must actually do something, or it shouldn't be called a law. If the initial state of a system is in a state of lowest possible entropy, and if one of those laws goes to work on that state then the entropy of the system in that state will NOT go down. And that is the second law of thermodynamics. If you did not mean to suggest that we can know a priori the 2nd law is true because it would be true in any logically possible universe whose behavior follows mathematical laws, please clarify. That is exactly what I meant to suggest, provided that the initial conditions were of very low entropy. But I thought you were talking about logically possible universes as well, not just our universe If the initial conditions were of high entropy then applying a law of physics to that mess would be just as likely to decrease its entropy as increase it, therefore the second law would not be true and time would have no arrow; in fact the very concept of time would have no meaning in that universe. the very fact that you were willing to discuss the Game of Life suggested this, since even though it's possible our universe could be a cellular automaton, I think we can be pretty confident it's not a 2-dimensional cellular automaton like the Game of Life! Well... you can make a Turing Machine from the Game of Life. And according to the Bekenstein Bound the maximum amount of information that the laws of physics allow you to store inside a sphere is NOT proportional to its 3D volume as you might expect but is instead proportional to the sphere's 2D surface area. So you could know all there is to know about what's going on inside a sphere just by looking at its surface, this has led some to propose what they call The Holographic principle, the idea is that the entire volume of our 3D universe is a projection from a 2D surface. Maybe they're right. As I've said I don't know what reality will turn out to be but whatever it is it's going to be weird. Another alternative would be to imagine you do have an infinite grid, but with a starting state where there are only a finite pattern of black squares surrounded by an infinite number of white squares, So the ratio of white squares to black is a finite number divided by infinity. No, because I said that in this case the region of the grid being *simulated* could still be finite So the rules of the Game of Life apply to some of the cells in the grid but do not apply to others. What rules govern which cells must obey the rules and which cells can ignore the rules, that is to say who is allowed to ignore the laws of physics in that universe? 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/groups/opt_out.
Re: What are wavefunctions?
On Thu, Jan 9, 2014 at 5:38 PM, LizR lizj...@gmail.com wrote: As a lot of people have now pointed out, physics can be local and relistic if time symmetry is valid. If time is symmetrical then retro-causality exists, so how can realism hold? How can the outcome of a coin flip today have a definite value independent of the observer if next year or next millennium someone can cause a change in today's coin flip? If realism holds under those circumstances then the word realism has no meaning. And by the way, if time is symmetrical then there is no point in ever actually performing an experiment because you would remember the future as clearly as you remember the past, so you would already remember the outcome of the experiment just as clearly as you remember setting up the experimental apparatus. 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/groups/opt_out.
Re: What are wavefunctions?
On Fri, Jan 10, 2014 at 12:20 PM, John Clark johnkcl...@gmail.com wrote: On Thu, Jan 9, 2014 Jesse Mazer laserma...@gmail.com wrote: I never claimed Liouville's theorem was a fundamental law of physics in itself, Good, I agree. rather it is derivable as a mathematical consequence of certain features of the fundamental laws. And of the initial conditions! No, it doesn't depend on initial conditions. No matter what set of initial microstates you choose at time T0, if you evolve each one forward to get a new set of microstates at time T1, then the volume of phase space occupied by the microstates at T0 will be precisely equal to the volume of phase space occupied by the microstates at T1. Do you disagree? Liouville's theorem is derived in deterministic classical mechanics. Then Liouville's theorem can only be approximately true. It'd be precisely true in a possible universe where the laws of classical physics hold exactly. Of course in our universe they don't, but there is apparently a quantum analogue of Liouville's theorem, though I don't understand it as well--see https://en.wikipedia.org/wiki/Liouville's_theorem_(Hamiltonian)#Quantum_Liouville_equation It [Liouville's theorem] only becomes statistical if you interpret the original set of microstates as representing your own uncertainty But that's the only way you can interpret it because the laws of physics insist that you will *always* be uncertain about the microstates, all you know are purely statistical things about the system, like its temperature and pressure. In classical physics there is no limit in principle to your knowledge of the microstate. And in quantum physics, there is nothing in principle preventing you from determining an exact quantum state for a system; only if you believe in some hidden-variables theory (like a theory that says that particles have precise position and momentum at all times, even though you can't measure them both simultaneously) would this be less-than-complete information about the microstate. This line of discussion got started because I was disputing your statement that we can derive the 2nd law in a *purely* logical way like 2+2=5, with no need to invoke knowledge about the laws of physics that was based on observation. This would imply that *any* logically possible mathematical laws of nature would obey the 2nd law. Yes, *any* logically possible mathematical law of nature must actually do something, or it shouldn't be called a law. If the initial state of a system is in a state of lowest possible entropy, and if one of those laws goes to work on that state then the entropy of the system in that state will NOT go down. And that is the second law of thermodynamics. Do you think my Toroidal Game of Life (a finite grid of cells with the edges identified, giving it the topology of a torus) is a mathematically well-defined possible universe? Do you disagree that starting from a randomly-chosen initial state which is likely to have something close to a 50:50 ratio of black to white squares, the board is likely to evolve to a state dominated by white squares, which would have lower entropy if we define macrostates in terms of the black:white ratio? If you did not mean to suggest that we can know a priori the 2nd law is true because it would be true in any logically possible universe whose behavior follows mathematical laws, please clarify. That is exactly what I meant to suggest, provided that the initial conditions were of very low entropy. The 2nd law is not restricted to initial conditions of very low entropy, it says that if the entropy is anything lower than the maximum it will statistically tend to increase, and if the entropy is at the maximum it is statistically more likely to stay at that value than to drop to any specific lower value. But I thought you were talking about logically possible universes as well, not just our universe If the initial conditions were of high entropy then applying a law of physics to that mess would be just as likely to decrease its entropy as increase it, therefore the second law would not be true and time would have no arrow; in fact the very concept of time would have no meaning in that universe. If the initial conditions deviated from maximum entropy even slightly, the second law says that an increase in entropy should be more likely than a decrease. For example, suppose we have 10,000 gas atoms in a box with no external forces acting on them, and we divide the box into two equal halves, and choose an initial macrostate where 5,100 atoms are in one half of the box and 4,900 atoms are in the other half. If the laws of physics applied to this initial macrostate were such that the ratio of atoms in each side was more likely to get *further* from 50:50 than 51:49 rather than closer to 50:50, that would be a clear violation of the 2nd law. Do you disagree? If you agree with that, then it's
Re: What are wavefunctions?
On Fri, Jan 10, 2014 at 12:43 PM, John Clark johnkcl...@gmail.com wrote: On Thu, Jan 9, 2014 at 5:38 PM, LizR lizj...@gmail.com wrote: As a lot of people have now pointed out, physics can be local and relistic if time symmetry is valid. If time is symmetrical then retro-causality exists, so how can realism hold? How can the outcome of a coin flip today have a definite value independent of the observer if next year or next millennium someone can cause a change in today's coin flip? If realism holds under those circumstances then the word realism has no meaning. There could be no change if the Novikov self-consistency principle holds (see https://en.wikipedia.org/wiki/Novikov_self-consistency_principle ), which is what physicists usually assume when analyzing theoretical scenarios where time travel could be possible, like traversable wormholes in general relativity. In this case the block time assumption holds, you just have a fixed 4D spacetime where all cause-and-effect sequences are already part of it, and any retrocausal influences must have been part of history all along rather than changing history from one sequence of events to an altered sequence. 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: What are wavefunctions?
On Jan 10, 2014, at 11:43 AM, John Clark johnkcl...@gmail.com wrote: On Thu, Jan 9, 2014 at 5:38 PM, LizR lizj...@gmail.com wrote: As a lot of people have now pointed out, physics can be local and relistic if time symmetry is valid. If time is symmetrical then retro-causality exists, so how can realism hold? How can the outcome of a coin flip today have a definite value independent of the observer if next year or next millennium someone can cause a change in today's coin flip? You are the obe who always says free will is meaningless. How can anyone change anything from how it would otherwise be if they and everything are ruled by the deterministic laws? The block time view makes this more clear. We can no more change the future than change the present or the past. If realism holds under those circumstances then the word realism has no meaning. Do you think realism is valid in the block time view? And by the way, if time is symmetrical then there is no point in ever actually performing an experiment because you would remember the future as clearly as you remember the past, The second law of thermodynamics prohibits this, as I explained in recent posts. Jason so you would already remember the outcome of the experiment just as clearly as you remember setting up the experimental apparatus. 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/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: What are wavefunctions?
On 11 January 2014 06:43, John Clark johnkcl...@gmail.com wrote: On Thu, Jan 9, 2014 at 5:38 PM, LizR lizj...@gmail.com wrote: As a lot of people have now pointed out, physics can be local and relistic if time symmetry is valid. If time is symmetrical then retro-causality exists, so how can realism hold? How can the outcome of a coin flip today have a definite value independent of the observer if next year or next millennium someone can cause a change in today's coin flip? If realism holds under those circumstances then the word realism has no meaning. Retro-causality (time symmetry is a better term) only exists at the quantum level. The laws of physics are time-symmetric, but constrained by boundary conditions. There is a very influential boundary condition in what we call the past, namely the Big Bang, plus less influential ones in the future, like the settings of measuring apparatuses. At all scales except that of individual quantum events, the pastward boundary condition washes out any noticeable effects of time symmetry. (That's what it means when we say that entropy increase involves coarse graining.) And by the way, if time is symmetrical then there is no point in ever actually performing an experiment because you would remember the future as clearly as you remember the past, so you would already remember the outcome of the experiment just as clearly as you remember setting up the experimental apparatus. I assume you're not so stupid as to think that's what I've been claiming, so I can only assume this is a deliberate attempt at mockery, directed at a straw man as such attempts usually are. I had hoped for a better standard of debate on this list. -- 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: What are wavefunctions?
On 11 January 2014 08:52, Jason Resch jasonre...@gmail.com wrote: On Jan 10, 2014, at 11:43 AM, John Clark johnkcl...@gmail.com wrote: On Thu, Jan 9, 2014 at 5:38 PM, LizR lizj...@gmail.com lizj...@gmail.com wrote: As a lot of people have now pointed out, physics can be local and relistic if time symmetry is valid. If time is symmetrical then retro-causality exists, so how can realism hold? How can the outcome of a coin flip today have a definite value independent of the observer if next year or next millennium someone can cause a change in today's coin flip? You are the obe who always says free will is meaningless. How can anyone change anything from how it would otherwise be if they and everything are ruled by the deterministic laws? The block time view makes this more clear. We can no more change the future than change the present or the past. The simplest way to understand this is to consider the past. If you look at the past, you see a perfect example of a block universe, with all the causal links (in either time direction) embedded in it. Now you just have to make the mental effort to extend that to the future, and to imagine that we are embedded, just as King Harold is embedded in 1066. Harold thinks that he is in a moving present but we can see his entire history. It's all there. Was he wrong? Yes, he was, we can see that now. Are we wrong? Ask someone in the next year/day/minute... -- 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: What are wavefunctions?
On 1/10/2014 9:43 AM, John Clark wrote: On Thu, Jan 9, 2014 at 5:38 PM, LizR lizj...@gmail.com mailto:lizj...@gmail.com wrote: As a lot of people have now pointed out, physics can be local and relistic if time symmetry is valid. If time is symmetrical I'm not sure what time is symmetrical means to you. It's the equations of dynamical evolution that are t-symmetric in physics (both classical and quantum-sans-collapse). then retro-causality exists, so how can realism hold? How can the outcome of a coin flip today have a definite value independent of the observer if next year or next millennium someone can cause a change in today's coin flip? If the coin flip today had a definite outcome why do suppose some one the future could simply choose it to be a different outcome?...free will? If realism holds under those circumstances then the word realism has no meaning. So you think realism would have no meaning in Laplace's deterministic universe? And by the way, if time is symmetrical then there is no point in ever actually performing an experiment because you would remember the future as clearly as you remember the past, so you would already remember the outcome of the experiment just as clearly as you remember setting up the experimental apparatus. Not if time is symmetrical == dynamical equations are t-symmetric and memory depends on the state of a lot of particles in your brain so that the 2nd law applies. 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/groups/opt_out.
Re: What are wavefunctions?
2014/1/9 John Clark johnkcl...@gmail.com On Wed, Jan 8, 2014 at 1:42 PM, Bruno Marchal marc...@ulb.ac.be wrote: Well, read Bell. I have. It shows how QM violates his inequality. I know, I demonstrated exactly that on this very list using my own language. And Bell knew of course that his inequality was not consistent with Quantum Mechanics, what he didn't know at the time was if his inequality was consistent with reality or if Quantum Mechanics was. That question was answered experimentally a couple of decades after Bell's theoretical work and the winner was Quantum Mechanics; so now we know that at least one of the assumptions that Bell made (realism, locality, high school math works) must be wrong. but Bell's inequality IS violated. Experimentally, Huh? This is a physical idea not a mathematical one, how else could it be proven wrong other than experimentally? But when you look at the many branches, at once [...] Unfortunately my eyesight isn't good enough to allow me to look at many branches of the multiverse at once. to me, the Bell's inequality experimental violation is a quite strong evidence for MW, that is QM-without collapse. To me Bell's inequality experimental violation is a quite strong evidence that reality is not local or not realistic or not either. MWI is not local As I said Liar Clark *even* when presented with evidences will continue till his death to lie... what's the point to discuss with such a guy ? Quentin so it could be correct, and emotionally it is my favorite interpretation, but logically I must admit that it is not the only interpretation that could be correct. Much as I dislike Copenhagen the fact is it's non-realistic so the violation of Bell's inequality is not rule it out. But Einstein's idea that things are realistic and local (and deterministic too although determinism was less important to Einstein than realism or locality) IS ruled out. 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/groups/opt_out. -- All those moments will be lost in time, like tears in rain. (Roy Batty/Rutger Hauer) -- 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: What are wavefunctions?
On Wed, Jan 8, 2014 at 2:34 PM, Jesse Mazer laserma...@gmail.com wrote: I think you will find relatively few physicists who expect that any new fundamental theory like quantum gravity will fail to have these [time] symmetries If so then time's arrow, that is to say time's asymmetry, is not the result of the fundamental laws of physics but is a statistical effect that could not be otherwise due to the nature of the initial conditions and the fact that there are just more ways to be disorganized than organized. by far the most popular explanation for macroscopic arrows of time is that it's due to the low-entropy boundary condition at the Big Bang And I have said exactly that approximately 6.02 * 10^23 times. 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/groups/opt_out.
Re: What are wavefunctions?
On Wed, Jan 8, 2014 at 7:52 PM, meekerdb meeke...@verizon.net wrote: All the physicists I know regard the second law of thermodynamics as a statistical, not fundamental, law. Exactly, and because statistics is based on pure logic and not on the trendy physical theory of the day if you asked those same physicists what idea is most likely to still seem valid to the scientific community in a thousand or even a million years they would probably say the second law of thermodynamics. 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/groups/opt_out.
Re: What are wavefunctions?
On Wed, Jan 8, 2014 at 2:41 PM, Jesse Mazer laserma...@gmail.com wrote For example, in Life one could define macrostates in terms of the ratio of white to black cells [...] In the Game of Life the number of black cells is always infinite, so I don't see how you can do any ratios. 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/groups/opt_out.
Re: What are wavefunctions?
On Wed, Jan 8, 2014 at 1:42 PM, Bruno Marchal marc...@ulb.ac.be wrote: Well, read Bell. I have. It shows how QM violates his inequality. I know, I demonstrated exactly that on this very list using my own language. And Bell knew of course that his inequality was not consistent with Quantum Mechanics, what he didn't know at the time was if his inequality was consistent with reality or if Quantum Mechanics was. That question was answered experimentally a couple of decades after Bell's theoretical work and the winner was Quantum Mechanics; so now we know that at least one of the assumptions that Bell made (realism, locality, high school math works) must be wrong. but Bell's inequality IS violated. Experimentally, Huh? This is a physical idea not a mathematical one, how else could it be proven wrong other than experimentally? But when you look at the many branches, at once [...] Unfortunately my eyesight isn't good enough to allow me to look at many branches of the multiverse at once. to me, the Bell's inequality experimental violation is a quite strong evidence for MW, that is QM-without collapse. To me Bell's inequality experimental violation is a quite strong evidence that reality is not local or not realistic or not either. MWI is not local so it could be correct, and emotionally it is my favorite interpretation, but logically I must admit that it is not the only interpretation that could be correct. Much as I dislike Copenhagen the fact is it's non-realistic so the violation of Bell's inequality is not rule it out. But Einstein's idea that things are realistic and local (and deterministic too although determinism was less important to Einstein than realism or locality) IS ruled out. 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/groups/opt_out.
Re: What are wavefunctions?
On Wed, Jan 8, 2014 at 6:59 PM, LizR lizj...@gmail.com wrote: I'm arguing that time is symmetric, Good luck winning that argument when nearly everything we observe, from cosmology to cooking, screams at us that time is NOT symmetric. Not at the quantum level, If so then obviously the quantum level is not the end of the story. it was actually discovered before Bell died that there's a perfectly reasonable explanation for how his inequality can be violated that retains locality and realism. Baloney. If that's the best refutation you can come up with, John Bell and Huw Price have nothing to fear. They have nothing to fear from me or the truth. If retro-causality exists then things are not local and not realistic either, so that possibility has not been ruled out experimentally. But the common sense view that most people, including Einstein, had about reality, that things are realistic and local, CAN be ruled out. And of all the people on the planet John Bell would be the last to disagree that if his inequality is violated then things are not local or not realistic or not either. 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/groups/opt_out.
Re: What are wavefunctions?
On Wed, Jan 8, 2014 at 7:11 PM, LizR lizj...@gmail.com wrote: The equations of Newtonian dynamics are time-symmetric, I know. similarly for relativity both SR and GR - I know and quantum mechanics is, too. I know. The only thing in the entirety f physics that isn't based on time symmetric equations is thermodynamics, That and the equations of cosmology. And astrophysics. And meteorology. And [...] 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/groups/opt_out.
Re: What are wavefunctions?
On 09 Jan 2014, at 17:53, John Clark wrote: On Wed, Jan 8, 2014 at 1:42 PM, Bruno Marchal marc...@ulb.ac.be wrote: Well, read Bell. I have. It shows how QM violates his inequality. I know, I demonstrated exactly that on this very list using my own language. And Bell knew of course that his inequality was not consistent with Quantum Mechanics, with Copenhagen QM. what he didn't know at the time was if his inequality was consistent with reality or if Quantum Mechanics was. That question was answered experimentally a couple of decades after Bell's theoretical work and the winner was Quantum Mechanics; Yes. so now we know that at least one of the assumptions that Bell made (realism, locality, high school math works) must be wrong. In Bell realism bears on the unique outcome. It is realism in Copenhagen QM. he does not address the question of locality in the non- collapse theory (which he does not like). but Bell's inequality IS violated. Experimentally, Huh? This is a physical idea not a mathematical one, how else could it be proven wrong other than experimentally? Sometimes it is good to be redundant on what is important :) But when you look at the many branches, at once [...] Unfortunately my eyesight isn't good enough to allow me to look at many branches of the multiverse at once. There is a technic: do QM. Just look at the terms in the solution of shroedinger equation, involving yourself, perhaps with Alice and Bob, etc. to me, the Bell's inequality experimental violation is a quite strong evidence for MW, that is QM-without collapse. To me Bell's inequality experimental violation is a quite strong evidence that reality is not local I am the one here who will tell you that 3p non locality is only a sound made by your lips and nothing else. Einstein was skeptical of the collapse of the wave because it introduce non locality, and non covariance. I think he is right. 3p non locality is telepathy or spooky action at a distance. It does not make sense to me. or not realistic or not either. MWI is not local Proof? The violation of Bell's inequality implies non locality for a realist interpretation of QM+collapse. When collapse never happens, all that occur comes from local interaction and interference, spreading at speed less than c. so it could be correct, and emotionally it is my favorite interpretation, but logically I must admit that it is not the only interpretation that could be correct. Much as I dislike Copenhagen the fact is it's non-realistic so the violation of Bell's inequality is not rule it out. But Einstein's idea that things are realistic and local (and deterministic too although determinism was less important to Einstein than realism or locality) IS ruled out. Proof? Quantum indeterminacy and quantum non locality are pure first person plural illusion (subjective, first person) in Everett. 3p determinism was as much important than 3p locality for Einstein. God does not play dice. He will keep that idea all his life. This is well known. There is few doubt, for me, that, like most cosmologist, he would have preferred many worlds than anything non deterministic or non local. I think (even more so after the reading of Jammer's book on Einstein's religion). Bruno 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/groups/opt_out. 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/groups/opt_out.
Re: What are wavefunctions?
On 09 Jan 2014, at 18:24, John Clark wrote: On Wed, Jan 8, 2014 at 2:41 PM, Jesse Mazer laserma...@gmail.com wrote For example, in Life one could define macrostates in terms of the ratio of white to black cells [...] In the Game of Life the number of black cells is always infinite, Because you restrict yourself to finite pattern. (Well, it is not a bad idea, to encode a state of mind, but that less sure for a universe of a god or something else). so I don't see how you can do any ratios. You can do local ratios, with suitable definition, and I guess that was Jesse meant. Bruno 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/groups/opt_out. 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/groups/opt_out.
Re: What are wavefunctions?
On Thu, Jan 9, 2014 at 12:58 PM, John Clark johnkcl...@gmail.com wrote: On Wed, Jan 8, 2014 at 7:11 PM, LizR lizj...@gmail.com wrote: The equations of Newtonian dynamics are time-symmetric, I know. similarly for relativity both SR and GR - I know and quantum mechanics is, too. I know. The only thing in the entirety f physics that isn't based on time symmetric equations is thermodynamics, That and the equations of cosmology. And astrophysics. And meteorology. And [...] http://groups.google.com/group/everything-list What equations of cosmology are there besides the equations of general relativity, used to model the entire universe? In general it's true that in some cases scientists use separate equations derived from observation to deal with large-scale phenomena, as in climate modeling. However, it is always assumed that reductionism holds, that the behavior of any large-scale system ultimately emerges statistically from the interaction of all its basic parts evolving according to more fundamental laws (as has been shown to be true of thermodynamic laws in statistical mechanics), even if in some cases it may be too difficult in practice to derive the higher-level equations from the fundamental ones (but it is possible for other cases besides thermodynamics, for example the interactions of certain molecules, normally the domain of chemistry, can be derived from basic quantum rules alone, as with the model of interacting water molecules discussed at http://www.udel.edu/PR/UDaily/2007/mar/water030207.html ). Do you disagree with reductionism in this sense? Are you suggesting that any equations governing higher-level systems are irreducible even in principle to lower-level laws (plus initial conditions or other boundary conditions)? 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: What are wavefunctions?
On Thu, Jan 9, 2014 at 12:08 PM, John Clark johnkcl...@gmail.com wrote: On Wed, Jan 8, 2014 at 2:34 PM, Jesse Mazer laserma...@gmail.com wrote: I think you will find relatively few physicists who expect that any new fundamental theory like quantum gravity will fail to have these [time] symmetries If so then time's arrow, that is to say time's asymmetry, is not the result of the fundamental laws of physics but is a statistical effect that could not be otherwise due to the nature of the initial conditions and the fact that there are just more ways to be disorganized than organized. But obviously if it's dependent on initial conditions then you can't derive it from logic alone, since it's logically possible that the initial conditions could have been different. And as I've said, there is also the fact that if the laws of physics don't conserve phase space volume, the 2nd law wouldn't hold either. by far the most popular explanation for macroscopic arrows of time is that it's due to the low-entropy boundary condition at the Big Bang And I have said exactly that approximately 6.02 * 10^23 times. OK, but you hadn't said that to *me* before--there are a lot of posts on this list, I don't read all of them. 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: What are wavefunctions?
On Thu, Jan 9, 2014 at 12:24 PM, John Clark johnkcl...@gmail.com wrote: On Wed, Jan 8, 2014 at 2:41 PM, Jesse Mazer laserma...@gmail.com wrote For example, in Life one could define macrostates in terms of the ratio of white to black cells [...] In the Game of Life the number of black cells is always infinite, so I don't see how you can do any ratios. John K Clark Maybe that would be true for some ideal Platonic version of the Game of Life on an infinite board, but any real-world implementation of a cellular automaton involves a finite number of squares--usually this is done with a periodic boundary condition, so squares on the left edge of the finite grid are defined to be neighbors of squares on the right edge, and squares on the top edge of the grid are defined to be neighbors of squares on the bottom edge. Another alternative would be to imagine you do have an infinite grid, but with a starting state where there are only a finite pattern of black squares surrounded by an infinite number of white squares, then you can expand the size of the simulated grid if the region of black squares approaches its border, so that the grid always remains larger than the region of black squares (you don't have to simulate regions beyond that because any region that's all-white on a given time-step, and doesn't have any black squares on its immediate border, will stay all-white on the next time-step). In either of these cases (though it's easier to analyze the periodic example since the grid size remains constant), the ratio of black squares to white squares on the simulated grid region at any given time is well-defined, so one can use this ratio to define the macrostate. And since the rules of the Game of Life aren't reversible, and many different initial states end up either in an all-white end state or an end-state with mostly white and a few blinking black shapes, I'm pretty sure this would be a case where an entropy defined in terms of these macrostates would tend to decrease from a randomly-chosen initial finite pattern of black squares. Do you disagree? (even if you're not as confident as I am that this would be true for the Game of Life, one could easily define less interesting transition rules where this is obviously the case, like a transition rule that says that only if a black square has a single black neighbor will it remain white, in every other case the square will turn white--hopefully you'd at least agree that in this case, entropy would tend to decrease from a random initial state on a periodic grid). 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: What are wavefunctions?
On Thu, Jan 9, 2014 at 11:53 AM, John Clark johnkcl...@gmail.com wrote: On Wed, Jan 8, 2014 at 1:42 PM, Bruno Marchal marc...@ulb.ac.be to me, the Bell's inequality experimental violation is a quite strong evidence for MW, that is QM-without collapse. To me Bell's inequality experimental violation is a quite strong evidence that reality is not local or not realistic or not either. MWI is not local so it could be correct, and emotionally it is my favorite interpretation, but logically I must admit that it is not the only interpretation that could be correct. Why do you say MWI is not local? Many physicists who advocate the MWI would disagree, like David Deutsch: http://arxiv.org/abs/1109.6223 http://arxiv.org/abs/quant-ph/9906007 This paper by Mark Rubin presents another defense of locality in the MWI: http://arxiv.org/abs/quant-ph/0103079 In it he mentions some of the history of defenses of MWI locality: In the Everett interpretation the nonlocal notion of reduction of the wavefunction is eliminated, suggesting that questions of the locality of quantum mechanics might indeed be more easily addressed. On the other hand, while wavefunctions do not suffer reduction in the Everett interpretation, nonlocality nevertheless remains present in many accounts of this formulation. In DeWitt’s (1970) often-quoted description, for example, “every quantum transition taking place on every star, in every galaxy, in every remote corner of the universe is splitting our local world on earth into myriads of copies of itself.” Contrary to this viewpoint, others argue (Page, 1982; Tipler, 1986, 2000; Albert and Loewer, 1988; Albert, 1992; Vaidman, 1994, 1998, 1999; Price, 1995; Lockwood, 1996; Deutsch, 1996; Deutsch and Hayden, 2000) that the Everett interpretation can in fact resolve the apparent contradiction between locality and quantum mechanics. In particular, Deutsch and Hayden (2000) apply the Everett interpretation to quantum mechanics in the Heisenberg picture, and show that in EPRB experiments,1 information regarding the correlations between systems is encoded in the Heisenberg-picture operators corresponding to the observables of the systems, and is carried from system to system and from place to place in a local manner. The picture which emerges is not one of measurement-type interactions “splitting the universe” but, rather, producing copies of the observers and observed physical systems which have interacted during the (local) measurement process (Tipler, 1986). Two more by Rubin: http://arxiv.org/abs/quant-ph/0204024 http://arxiv.org/abs/0909.2673 Conceptually it's not that hard to see how the MWI offers a loophole in Bell's proof--Bell assumed that each spin measurement yielded a single definite outcome, but if you instead imagine that each spin measurement causes the experimenter to split into copies who observe different outcomes and aren't aware of one another, then the universe doesn't have to decide which version of experimenter #1 gets matched up to which version of experimenter #2 until there's been time for signals moving at the speed of light to travel from each experimenter to someone in the middle who can be aware of the results at both locations. If that isn't clear, in post #11 at http://www.physicsforums.com/showthread.php?t=206291 I gave a sort of toy model of how duplicating the experimenters at different locations and matching them up later can allow for each of the matched pairs to observe Bell inequality violations without any need for 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 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: What are wavefunctions?
On 1/9/2014 9:45 AM, John Clark wrote: On Wed, Jan 8, 2014 at 6:59 PM, LizR lizj...@gmail.com mailto:lizj...@gmail.com wrote: I'm arguing that time is symmetric, Good luck winning that argument when nearly everything we observe, from cosmology to cooking, screams at us that time is NOT symmetric. Not at the quantum level, If so then obviously the quantum level is not the end of the story. it was actually discovered before Bell died that there's a perfectly reasonable explanation for how his inequality can be violated that retains locality and realism. Baloney. If that's the best refutation you can come up with, John Bell and Huw Price have nothing to fear. They have nothing to fear from me or the truth. If retro-causality exists then things are not local and not realistic either, so that possibility has not been ruled out experimentally. Retro-causality is always present in a deterministic system because boundary conditions can be in the future instead of the past. Newtonian mechanics included retro-causality and was still realistic (in the sense of only one definite result). MWI is the same, deterministic and one definite result - except the definite result includes non-communicating worlds including the observers. Maybe it should be called the hidden worlds theory. Brent But the common sense view that most people, including Einstein, had about reality, that things are realistic and local, CAN be ruled out. And of all the people on the planet John Bell would be the last to disagree that if his inequality is violated then things are not local or not realistic or not either. 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/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: What are wavefunctions?
On 1/9/2014 9:58 AM, John Clark wrote: That and the equations of cosmology. The equations of cosmology, Einsteins or Wheeler-Dewitt, are T-symmetric. You seem to have confused the equations of evolution and the boundary conditions. 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/groups/opt_out.
Re: What are wavefunctions?
On Thu, Jan 9, 2014 at 2:02 PM, Jesse Mazer laserma...@gmail.com wrote: And as I've said, there is also the fact that if the laws of physics don't conserve phase space volume, the 2nd law wouldn't hold either. You've got it backwards, there is no fundamental law of physics concerning the conservation of phase space that forces matter to behave in certain ways, rather it's just a natural consequence of the FIRST law of thermodynamics and the statistical fact that if you make a change in a highly orders system you will probably make it more disordered because there are far fewer ordered states than disordered states. Liouville's equation is all about statistics, the variables in it determine the phase space distribution and that determines the PROBABILITY a system of things will be in a particular infinitesimal phase space volume. For example, in Life one could define macrostates in terms of the ratio of white to black cells [...] In the Game of Life the number of black cells is always infinite, so I don't see how you can do any ratios. Maybe that would be true for some ideal Platonic version of the Game of Life on an infinite board, but any real-world implementation of a cellular automaton involves a finite number of squares Maybe not. The universe is certainly a real world implementation and it might be infinite and it might be a cellular automation, that's what Stephen Wolfram thinks. usually this is done with a periodic boundary condition, so squares on the left edge of the finite grid are defined to be neighbors of squares on the right edge, and squares on the top edge of the grid are defined to be neighbors of squares on the bottom edge. Then the rules governing the game have been changed. Another alternative would be to imagine you do have an infinite grid, but with a starting state where there are only a finite pattern of black squares surrounded by an infinite number of white squares, So the ratio of white squares to black is a finite number divided by infinity. Perhaps that's what a Black Hole is, a place where God tried to divide by zero. 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/groups/opt_out.
Re: What are wavefunctions?
On Thu, Jan 9, 2014 at 3:58 PM, John Clark johnkcl...@gmail.com wrote: On Thu, Jan 9, 2014 at 2:02 PM, Jesse Mazer laserma...@gmail.com wrote: And as I've said, there is also the fact that if the laws of physics don't conserve phase space volume, the 2nd law wouldn't hold either. You've got it backwards, there is no fundamental law of physics concerning the conservation of phase space that forces matter to behave in certain ways, rather it's just a natural consequence of the FIRST law of thermodynamics and the statistical fact that if you make a change in a highly orders system you will probably make it more disordered because there are far fewer ordered states than disordered states. I never claimed Liouville's theorem was a fundamental law of physics in itself, rather it is derivable as a mathematical consequence of certain features of the fundamental laws. What I've read indicates that Liouville's theorem applies to any system that obeys Hamilton's equations (see the last paragraph on p. 549 of Taylor's Classical Mechanics at http://books.google.com/books?id=P1kCtNr-pJsCpg=PA549 for example), but I'm not sure if it's true that any logically possible laws that conserve energy (obeying the first law of thermodynamics) also obey Hamilton's equations...the Hamiltonian is not always equal to the total energy, see http://physics.stackexchange.com/questions/11905/when-is-the-hamiltonian-of-a-system-not-equal-to-its-total-energy Liouville's equation is all about statistics, the variables in it determine the phase space distribution and that determines the PROBABILITY a system of things will be in a particular infinitesimal phase space volume. Liouville's theorem is derived in deterministic classical mechanics. If you take a volume of phase space, each point in that volume is a specific microstate, and if you evolve each microstate forward for some time T using the deterministic equations of physics, you get a later set of microstates which occupy their own volume in phase space. Liouville's theorem just says the two volumes must be equal. It only becomes statistical if you interpret the original set of microstates as representing your own uncertainty--if you just know the original macrostate, you may choose to consider the statistical ensemble of microstates compatible with that macrostate, then they will give the volume of phase space that you start with. But that's just an extra layer of interpretation, Liouville's theorem itself is not really statistical. For example, in Life one could define macrostates in terms of the ratio of white to black cells [...] In the Game of Life the number of black cells is always infinite, so I don't see how you can do any ratios. Maybe that would be true for some ideal Platonic version of the Game of Life on an infinite board, but any real-world implementation of a cellular automaton involves a finite number of squares Maybe not. The universe is certainly a real world implementation and it might be infinite and it might be a cellular automation, that's what Stephen Wolfram thinks. This line of discussion got started because I was disputing your statement that we can derive the 2nd law in a *purely* logical way like 2+2=5, with no need to invoke knowledge about the laws of physics that was based on observation. This would imply that *any* logically possible mathematical laws of nature would obey the 2nd law. So the question of whether space in *our* universe is infinite or finite is irrelevant to the discussion, because it's certainly logically possible to have a universe with finite space. If you did not mean to suggest that we can know a priori the 2nd law is true because it would be true in any logically possible universe whose behavior follows mathematical laws, please clarify. But I thought you were talking about logically possible universes as well, not just our universe--the very fact that you were willing to discuss the Game of Life suggested this, since even though it's possible our universe could be a cellular automaton, I think we can be pretty confident it's not a 2-dimensional cellular automaton like the Game of Life! usually this is done with a periodic boundary condition, so squares on the left edge of the finite grid are defined to be neighbors of squares on the right edge, and squares on the top edge of the grid are defined to be neighbors of squares on the bottom edge. Then the rules governing the game have been changed. I think most any book or website that defines the rules of the Game of Life will just state the transition rules for how each cell's state depends on the state of that cell and its nearest neighbors on the previous time-step, they don't say anything about whether the topology of the board is that of a torus (which is topologically equivalent to a square with the edges identified in the way I described, as discussed at http://plus.maths.org/content/space-do-all-roads-lead-home )
Re: What are wavefunctions?
On 10 January 2014 06:58, John Clark johnkcl...@gmail.com wrote: On Wed, Jan 8, 2014 at 7:11 PM, LizR lizj...@gmail.com wrote: The equations of Newtonian dynamics are time-symmetric, I know. similarly for relativity both SR and GR - I know and quantum mechanics is, too. I know. The only thing in the entirety f physics that isn't based on time symmetric equations is thermodynamics, That and the equations of cosmology. And astrophysics. And meteorology. And [...] So stop pretending otherwise. As a lot of people have now pointed out, physics can be local and relistic if time symmetry is valid. Time symmetry appears to be valid, as you just agreed. Hence physics can be local and realistic. -- 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: What are wavefunctions?
On 1/9/2014 2:26 PM, Jesse Mazer wrote: Liouville's theorem is derived in deterministic classical mechanics. If you take a volume of phase space, each point in that volume is a specific microstate, and if you evolve each microstate forward for some time T using the deterministic equations of physics, you get a later set of microstates which occupy their own volume in phase space. Liouville's theorem just says the two volumes must be equal. It only becomes statistical if you interpret the original set of microstates as representing your own uncertainty--if you just know the original macrostate, you may choose to consider the statistical ensemble of microstates compatible with that macrostate, then they will give the volume of phase space that you start with. But that's just an extra layer of interpretation, Liouville's theorem itself is not really statistical. Right. And entropy, the log of the number of possible states, only increases when possible states is defined by some macroscopic constraint. There is always a finer microstate definition of possible states such that the number and the entropy don't increase. Entropy is a consequence of coarse-graining. 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/groups/opt_out.