Retrocausality in Quantum Mechanics (SEP)

[Philip Thrift]

new article in SEP

First published Mon Jun 3, 2019

https://plato.stanford.edu/entries/qm-retrocausality/

authors:

Simon Friederich - http://simonfriederich.eu/

Peter Evans - https://hapi.uq.edu.au/profile/450/peter-evans

@philipthrift

[Bruno Marchal]

With Mechanism, there is a “Turing-thropic” sort of retrocausality in the phenomenology of matter, quite similar to Saibal Mitra’s idea that the first-person experience backtrack from the cul-de-sac world (dead end).

That remains to be confirmed in the “theology of the universal löbian machine", and that requires a *lot* of works.

Bruno

@philipthrift

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[spudb...@aol.com]

Physicists, John Cramer, and Jack Sarfatti, were big into this, some years ago. 

https://groups.google.com/d/msgid/everything-list/7D6C8F69-C6ED-4C6B-A929-A2713F8CCFD1%40ulb.ac.be

.

[Philip Thrift]

This

https://aeon.co/essays/can-retrocausality-solve-the-puzzle-of-action-at-a-distance

is by a philosopher and a physicist.

Huw Price is Bertrand Russell Professor of Philosophy and a fellow of Trinity College at the University of Cambridge. 

Ken Wharton is professor of physics and astronomy at San José State University.

@philipthrift

[spudb...@aol.com]

Sure, Huw Price, Times Arrow. For time stuff, we should throw in Ron Mallett and Carlo Rovelli as well. 

For me, with physics and astronomy, I always seek the pay out (Cynically). Does it make things better for people? Can we do something, not even useful, but usable? Are we just supposed to ooh, and awww? Many people are terrific at doing this. Do, continue, despite my cynicism. 

-----Original Message-----
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To: Everything List <everyth...@googlegroups.com>
Sent: Tue, Jun 4, 2019 2:15 pm
Subject: Re: Retrocausality in Quantum Mechanics (SEP)

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[Philip Thrift]

As for quantum stochastic retrodependency (which physicists avoid like vampires avoid sunlight), it simplifies the "puzzles" of QM, meaning that, for the most part, the articles you see talking about the "spooky action at a distance" or "many wolds" of QM you can dump in the trashcan and save a lot of time!

If quantum computers become a reality, you might be able to see it at work in a computer you could program.

@philiphrift

[Bruce Kellett]

On Wed, Jun 5, 2019 at 1:15 PM Philip Thrift <cloud...@gmail.com> wrote:

As for quantum stochastic retrodependency (which physicists avoid like vampires avoid sunlight), it simplifies the "puzzles" of QM, meaning that, for the most part, the articles you see talking about the "spooky action at a distance" or "many wolds" of QM you can dump in the trashcan and save a lot of time!

The trouble is that these retrocausal "explanations" do not actually explain anything! They sound like they should: "The formation of the EPR pair depends on the future setting of the polarises as well as on the state preparation." (Or something similar). But no detailed dynamics are ever given, and the supposed explanation is even more mystical than "spooky action at a distance...."

Bruce

[Philip Thrift]

I've given a retreocausal mechanism of course:

https://codicalist.wordpress.com/2018/03/16/mirror-mirror/

If you know of other references, let me know.

@philipthrift

[Lawrence Crowell]

On Tuesday, June 4, 2019 at 10:22:51 PM UTC-5, Bruce wrote:

On Wed, Jun 5, 2019 at 1:15 PM Philip Thrift <cloud...@gmail.com> wrote:

As for quantum stochastic retrodependency (which physicists avoid like vampires avoid sunlight), it simplifies the "puzzles" of QM, meaning that, for the most part, the articles you see talking about the "spooky action at a distance" or "many wolds" of QM you can dump in the trashcan and save a lot of time!

The trouble is that these retrocausal "explanations" do not actually explain anything! They sound like they should: "The formation of the EPR pair depends on the future setting of the polarises as well as on the state preparation." (Or something similar). But no detailed dynamics are ever given, and the supposed explanation is even more mystical than "spooky action at a distance...."

Bruce

Bingo --- ting ding ting ding ... . Thanks Bruce. Since QM is time symmetric or invariant in its form with respect to time direction whether you define time forwards or backwards, or do so for some partition of a density matrix or wave, makes no difference. Retrocausality in effect solves nothing. Nonlocality and the contextual nature of QM, eg the Mermin-Peres square that gives Kochen-Specker, have no definition with respect to any time direction. If you have locality in QM then it is still not possible to think meaningfully of counterfactual definiteness (CFD), or if QM is regarded as nonlocal only then can you have CFD, such as with Many Worlds Interpretation. It makes no difference whether the observables measured are considered forwards or backwards evolving.

LC

[Bruce Kellett]

On Wed, Jun 5, 2019 at 7:48 PM Philip Thrift <cloud...@gmail.com> wrote:

I've given a retreocausal mechanism of course:

https://codicalist.wordpress.com/2018/03/16/mirror-mirror/

As I said, even more mystical than 'spooky-action-at-a-distance'.

Bruce

[Philip Thrift]

It solves wasting any time reading papers about QM many worlds, non-locality, all the nonsense you read today.

[If one views QM as a generalized measure on a space of histories, then one sees not only how quantal processes differ from classical stochastic processes (the main difference, they satisfy different sum rules), but also how closely the two resemble each other.]

via Rafael Sorkin

@philipthrift

[Philip Thrift]

Anyway, as you know well, I "adopted" the retrocausal view 20 years ago via Victor J. Stenger, who pointed of course to Huw Price.

@philipthrift

[Philip Thrift]

Just out:

https://www.newscientist.com/article/mg24232330-200-weve-seen-signs-of-a-mirror-image-universe-that-is-touching-our-own/

We've seen signs of a mirror-image universe that is touching our own.

New experiments are revealing hints of a world and a reality that are complete reflections of ours. 

@philipthrift 

[Bruce Kellett]

You should stop being impressed by bullshit such as this in New Scientist, Philip -- NS is about as unreliable a science reporting rag as you can get!

Bruce 

[spudb...@aol.com]

I read your article, and noticed that there was a New Scientist article (stub) available with an identical term, Mirrorverse, etc to your article. Nothing retrocausal in it as far as I could glance at. This was more identifying dark matter as the mirror, and dark matter was decayed neutrons. Can we do anything fun with your retrocausal mechanism? I had to ask!    Meanwhile...

https://www.newscientist.com/article/mg24232330-200-weve-seen-signs-of-a-mirror-image-universe-that-is-touching-our-own/

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Sent: Wed, Jun 5, 2019 5:48 am
Subject: Re: Retrocausality in Quantum Mechanics (SEP)

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[Philip Thrift]

It's not that i'm impressed by a CPT-symmetric biverse (introduced by others, including Victor J. Stenger, "The Fallacy of Fine Tuning"). It' that it's better than all the (other) BS.

@philipthrift

 

[Philip Thrift]

https://arxiv.org/abs/1803.08928

CPT-Symmetric Universe

Latham Boyle, Kieran Finn, Neil Turok

(Submitted on 23 Mar 2018 (v1), last revised 2 Dec 2018 (this version, v3))

We propose that the state of the universe does {\it not} spontaneously violate CPT. Instead, the universe after the big bang is the CPT image of the universe before it, both classically and quantum mechanically. The pre- and post-bang epochs comprise a universe/anti-universe pair, emerging from nothing directly into a hot, radiation-dominated era. CPT symmetry selects a unique QFT vacuum state on such a spacetime, providing a new interpretation of the cosmological baryon asymmetry, as well as a remarkably economical explanation for the cosmological dark matter. Requiring only the standard three-generation model of particle physics (with right-handed neutrinos), a ℤ2 symmetry suffices to render one of the right-handed neutrinos stable. We calculate its abundance from first principles: matching the observed dark matter density requires its mass to be 4.8×108 GeV. Several other testable predictions follow: (i) the three light neutrinos are Majorana and allow neutrinoless double β decay; (ii) the lightest neutrino is massless; and (iii) there are no primordial long-wavelength gravitational waves. We mention connections to the strong CP problem and the arrow of time.

@philipthrift 

 

 

[Philip Thrift]

https://arxiv.org/abs/1710.00767

New Search for Mirror Neutrons at HFIR

L. J. Broussard, K. M. Bailey, W. B. Bailey, J. L. Barrow, B. Chance, C. Crawford, L. Crow, L. DeBeer-Schmitt, N. Fomin, M. Frost, A. Galindo-Uribarri, F. X. Gallmeier, L. Heilbronn, E. B. Iverson, Y. Kamyshkov, C.-Y. Liu, I. Novikov, S. I. Pentillä, A. Ruggles, B. Rybolt, M. Snow, L. Townsend, L. J. Varriano, S. Vavra, A. R. Young

(Submitted on 2 Oct 2017 (v1), last revised 25 Oct 2017 (this version, v2))

The theory of mirror matter predicts a hidden sector made up of a copy of the Standard Model particles and interactions but with opposite parity. If mirror matter interacts with ordinary matter, there could be experimentally accessible implications in the form of neutral particle oscillations. Direct searches for neutron oscillations into mirror neutrons in a controlled magnetic field have previously been performed using ultracold neutrons in storage/disappearance measurements, with some inconclusive results consistent with characteristic oscillation time of τ∼10~s. Here we describe a proposed disappearance and regeneration experiment in which the neutron oscillates to and from a mirror neutron state. An experiment performed using the existing General Purpose-Small Angle Neutron Scattering instrument at the High Flux Isotope Reactor at Oak Ridge National Laboratory could have the sensitivity to exclude up to τ<15~s in 1 week of beamtime and at low cost.

@philipthrift

[Bruce Kellett]

Apart from not solving anything, and the problem of the absence of any dynamical explanation as to how retrocausality might work to eliminate non-locality, the real problem is that retrocausal explanations have been ruled out experimentally.

The seminal experiment by Aspect, et al., published in 1982 really put the last nail in the coffin of retrocausal explanations. The point is that in Aspect's experiment, the polariser settings were chosen while the photons were in flight -- in other words, at some time after the singlet pair was created. So there is no way the photons, travelling back in time at the speed of light, could ever reach the original singlet state after they had detected the polariser setting. The best they could do would be to carry the polariser setting back half way, but no way could they reach back to the interaction that created the original singlet state.

So all these years, Huw Price and his cronies have been talking absolute rubbish -- their theory has already been falsified by experiment.

Bruce 

[Alan Grayson]

Didn't Vic Stenger also claim that retro-causality solved the quantum non-locality problem? AG 

[Philip Thrift]

Rubbish. A complete misunderstanding of quantum mechanics. 

Retrocausal hidden variable models are completely compatible with experiments, unless QM itself is wrong.

@philipthrift

[Philip Thrift]

Exactly so!

It seems some forget history, or as confused as they were 20 years ago.

@philipthrift 

[Bruce Kellett]

If retrocausality is right, then QM itself is certainly wrong. In the EPR situation, the singlet state is rotationally symmetric in standard QM, and this cannot be the case if that state is dependent on the future polariser settings. Conversely, if QM is right, retrocausality is impossible.

Bruce 

[Lawrence Crowell]

A little thought should indicate this. Quantum mechanics is invariant with respect to time direction. This then means whether you consider the causal direction of a Greens function forwards or backwards it makes no difference. In fact a standard Green's function is of the form

G(x,x',t,t') = 1/4π (|x – x'|^2 - |t - t'|^2)^{-1}

so how in the hell can any signal with a propagator that is time reversal invariant have any measurable impact of this sort? If this were the case, that a preferred time direction in QM absorbed the appearance of nonlocality, this would imply QM is not time direction invariant.

I agree Price, Wharton, and other have been wasting their time. When Stenger wrote about this idea I arm wrestled with him. It is just patently wrong that one can do this. In fact one can't try to reconstruct nonlocality with tachyons, and this has been tried. 

LC

[Philip Thrift]

Very funny. Totally non-sequitur, as usual.

Retrocasation in quantum computing:

A Retrocausal Model of the Quantum Computational Speedup

in

AAAS Pacific Division

2016 San Diego Meeting

Symposium Abstracts

Quantum Retrocausation III

https://pdfs.semanticscholar.org/4e9f/f4d375626b2cd051b49dda2047b040d8e9b5.pdf

Bob, the problem setter, hides a ball in one of four drawers. Alice, the problem solver, is to locate it. Quantumly, this can be done by opening just one drawer. We explain this quantum speedup with retrocausality.

The initial measurement randomly selects a drawer number out of a mixture of the four possible numbers. Bob unitarily sends it into the desired number of the drawer with the ball. This yields the algorithm input state to Bob and any external observer, not to Alice. It would tell her the solution of the problem before she opens any drawer. To Alice, the projection of the quantum state induced by the initial measurement should be retarded to the end of her search. The input state to her remains the mixed one. Alice sends it unitarily into a mixture of tensor products, each a drawer number and the corresponding solution. She reads – measures – the solution corresponding to the number chosen by Bob.

Mathematically, this final measurement could select back in time any part of the random outcome of the initial measurement. The assumption it selects half of it explains the speedup. This projects the input state to Alice on one of lower entropy where she knows half of the information that specifies the number of the drawer with the ball. The quantum algorithm is a sum over classical histories in each of which Alice knows in advance one of the possible halves of the information and opens only the drawers required to find the other half. A similar explanation applies to quantum oracle computing.

Reversing cause and effect is no trouble for quantum computers

https://phys.org/news/2018-07-reversing-effect-quantum.html

https://journals.aps.org/prx/abstract/10.1103/PhysRevX.8.031013

Causal asymmetry is one of the great surprises in predictive modeling: The memory required to predict the future differs from the memory required to retrodict the past. There is a privileged temporal direction for modeling a stochastic process where memory costs are minimal. Models operating in the other direction incur an unavoidable memory overhead. Here, we show that this overhead can vanish when quantum models are allowed. Quantum models forced to run in the less-natural temporal direction not only surpass their optimal classical counterparts but also any classical model running in reverse time. This holds even when the memory overhead is unbounded, resulting in quantum models with unbounded memory advantage.

@philipthrfit

[Bruno Marchal]

If QM with collapse is right, I would understand and agree. That is why Deutsch see the “retrocausality” has a semantic variant of the many-worlds interpretations, but I have not entirely figure out if this makes sense in the Omnes-Griffith-Gelman-Hartle view of the many-worlds. That would be nice and eliminate t’hooft’s need of “super-determinism” (mechanism is trivially "super-deterministic" in the third person view, but not at all in the first person views—that plays a role for free-will/self-determination). 

Bruno

Bruce 

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[Bruce Kellett]

On Tue, Jun 11, 2019 at 3:53 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 10 Jun 2019, at 08:54, Bruce Kellett <bhkel...@gmail.com> wrote:

 

On Mon, Jun 10, 2019 at 4:34 PM Philip Thrift <cloud...@gmail.com> wrote:

Retrocausal hidden variable models are completely compatible with experiments, unless QM itself is wrong.

If retrocausality is right, then QM itself is certainly wrong. In the EPR situation, the singlet state is rotationally symmetric in standard QM, and this cannot be the case if that state is dependent on the future polariser settings. Conversely, if QM is right, retrocausality is impossible.

If QM with collapse is right, I would understand and agree. That is why Deutsch see the “retrocausality” has a semantic variant of the many-worlds interpretations, but I have not entirely figure out if this makes sense

It makes no sense at all! Deutsch has gone completely off the rails over quantum mechanics. He is essentially abandoning the theory as it currently stands. The argument from symmetry is, to my mind, a total killer of any retrocausal explanation -- retrocausality must destroy the very symmetry that is at the heart of the QM predictions for the singlet state, Collapse and many worlds are all irrelevant to this argument.

The non-locality of the quantum singlet state is irreducible, and neither retrocausality nor many worlds has any impact on this central conclusion.

Bruce

[Philip Thrift]

"quantum mechanics [is]  a theory of quantal histories, without ever needing to call on state-vectors, measurements, or external agents as fundamental notions"

Rafael Sorkin

https://www.perimeterinstitute.ca/people/rafael-sorkin

The whole thing about  quantum "states" is just a cult view, like a religion.

@philipthrift

[Bruce Kellett]

Sorkin has a long history of misunderstanding the basis of quantum mechanics. Paths, or quantum histories, are just a way of calculating probabilities -- there is no ontology there. Just like Feynman diagrams, virtual particles and all that. Merely calculational techniques with no ontological content. Quantal histories do not eliminate the notion of the "quantum state".

Besides, quantal histories no more eliminate non-locality than does retrocausality or many worlds.

Bruce 

@philipthrift

[Philip Thrift]

Of course in the reflective histories model there are histories and (their mirror images) futures.

- https://codicalist.wordpress.com/2018/03/16/mirror-mirror/

Like I've said, people can wander through life believing in what they want. I did not have God speak to me and tell me the absolute truth about these things, like some apparently have.

@philipthrift 

[Bruce Kellett]

You have a remarkable ability to avoid the issues, Phil. Enlighten me about what reflective histories can tell me about the world, and what particular predictions they can make that cannot be obtained in other ways.

In other words, why should I care a stuff about what you are saying?

Bruce

[Philip Thrift]

Is there a particular detail in the article "The Reflective Path Integral" you are pointing to? 

It seems to me there are umpteen "other ways" of predicting the same things. That's just Quine's scientific underdetermination of scientific theories.

I was surprised to come across "mirror matter":

The theory of mirror matter predicts a hidden sector made up of a copy of the Standard Model particles and interactions but with opposite parity.

—arXiv:1710.00767

That seems closer to the Reflective Path Integral than to Many Worlds, or to any other QM model.

The path integral is the wave of the future.

@philipthrift

[Philip Thrift]

Also you say "Sorkin has a long history of misunderstanding the basis of quantum mechanics."

Really?

     https://en.wikipedia.org/wiki/Rafael_Sorkin

Does he misunderstand it, but you understand it? Who are you? can you prove your claim that he misunderstands it?

@philipthrift

[Philip Thrift]

BTW, I developed the Reflective Path Integral last year, and then more than a year later I see the arXiv article on mirror matter. 

Clearly a case of precognition. :)

@philipthrift

[Lawrence Crowell]

On Tuesday, June 11, 2019 at 1:14:32 AM UTC-5, Bruce wrote:

On Tue, Jun 11, 2019 at 3:53 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 10 Jun 2019, at 08:54, Bruce Kellett <bhkel...@gmail.com> wrote:

 

On Mon, Jun 10, 2019 at 4:34 PM Philip Thrift <cloud...@gmail.com> wrote:

Retrocausal hidden variable models are completely compatible with experiments, unless QM itself is wrong.

If retrocausality is right, then QM itself is certainly wrong. In the EPR situation, the singlet state is rotationally symmetric in standard QM, and this cannot be the case if that state is dependent on the future polariser settings. Conversely, if QM is right, retrocausality is impossible.

If QM with collapse is right, I would understand and agree. That is why Deutsch see the “retrocausality” has a semantic variant of the many-worlds interpretations, but I have not entirely figure out if this makes sense

It makes no sense at all! Deutsch has gone completely off the rails over quantum mechanics. He is essentially abandoning the theory as it currently stands. The argument from symmetry is, to my mind, a total killer of any retrocausal explanation -- retrocausality must destroy the very symmetry that is at the heart of the QM predictions for the singlet state, Collapse and many worlds are all irrelevant to this argument.

The non-locality of the quantum singlet state is irreducible, and neither retrocausality nor many worlds has any impact on this central conclusion.

Bruce

This trend has galloped off into some sort of nonsense. Some of these people are fairly well known, such as Dowkers, Wharton, Sorkin and Deutsch, but they have all gone into some sort of fantasy land. It is too bad in a way that Bohr is not still alive to shake his finger at these folks. It appears that in some ways this is a case of Alan Ginsburg's Howl, with "I have seen the best minds of this generation go mad." These ideas are so patently wrong, that with a fairly basic even minimal argument based on plain vanilla QM they can be seen as false.

LC

[Philip Thrift]

On Tuesday, June 11, 2019 at 6:38:41 AM UTC-5, Lawrence Crowell wrote:

...

This trend has galloped off into some sort of nonsense. Some of these people are fairly well known, such as Dowkers, Wharton, Sorkin and Deutsch, but they have all gone into some sort of fantasy land. It is too bad in a way that Bohr is not still alive to shake his finger at these folks. It appears that in some ways this is a case of Alan Ginsburg's Howl, with "I have seen the best minds of this generation go mad." These ideas are so patently wrong, that with a fairly basic even minimal argument based on plain vanilla QM they can be seen as false.

LC

 

So Fay Dowker and Rafael Sorkin 

   https://en.wikipedia.org/wiki/Fay_Dowker

   https://en.wikipedia.org/wiki/Rafael_Sorkin

are now in fantasy land. 

You want to turn physics into a religious fundamentalist cult.

@philipthrift

[Lawrence Crowell]

Sorry, but there are trends in academia where people by virtue of their position are able to promote nonsense. I think Jonathan Swift had a bit to say with the the floating island of Laputia, which was a knock on academia. 

The problem with Dowker and her path integral ideas is the path integral is a math method; it has no additional physical content. In fact in general in the way it is written it has less content because it is expanded around a classical extremum. QFT is much the same. QFT sets commutators of observables with spacelike separations to zero, when quantum mechanics in its pure setting tells us there is nonlocality and this condition is an auxiliary postulate meant to ease calculations. String theory has some "funnies" to it as well. The interesting thing about the holographic principle with black holes is it tells us that quantum fields are projections from fields near the horizon where Lorentz symmetry has these quantum field in a time dilated and nonrelativistic QM form. In effect plain vanilla QM, the stuff in Merzbacher or Cohen-Tannoudji etc is really the fundamental stuff. 

Along these lines with fundamental physics, with exceptional group theory, Leech lattice, and Jordan algebras etc, the theta representation of these involve equations that in complex form are Schrodinger equations. In a Euclideanized form they are heat equations with heat kernel solutions. When applied to the integral representation of qubits on a stretched horizon it does suggest that in some fancy way, say with relationships between entanglements, causality and spacetime, the most fundamental theory of the universe is just plain QM. 

I would strongly advise anyone to avoid ideas about hidden variables or in this case ideas of advanced potentials that in ways "wire up" the appearance of nonlocality with local rules. For various reasons these ideas are not consistent with QM, and at the end of it all these ideas do not produce QM as some derived result, but rather demolish it. 

LC

[Philip Thrift]

So Dowker (professor of theoretical physics at Imperial College London) is misguided and you are not. Who are you?

The main idea of "Lost in Math" (Sabine Hossenfelder) addresses the fundamentalist mindset expressed above that traps many (she would know more how many, being around them) physicists.

Better to consider Feyerabend and reject fundamentalist certainty.

"All descriptions of reality are inadequate. You think that this one-day fly, this little bit of nothing, a human being--according to today's cosmology!--can figure it all out? This to me seems so crazy! It cannot possibly be true!"

https://blogs.scientificamerican.com/cross-check/was-philosopher-paul-feyerabend-really-science-s-worst-enemy/

@philipthrift

[Philip Thrift]

See also:

via https://twitter.com/skdh/status/1137579084341547008

The End of Theoretical Physics As We Know It

by

Sabine Hossenfelder

August 27, 2018

https://www.quantamagazine.org/the-end-of-theoretical-physics-as-we-know-it-20180827/

John Carlos Baez @johncarlosbaez

I see your headline-writing goblins are up to their usual tricks.  "The End of Theoretical Physics as We Know It".  That sounds like a great way to get people's attention.  Next week: "Theoretical Physics Over and Done With - Universe Ending Soon!"

Sabine Hossenfelder @skdh

Replying to  @johncarlosbaez

 

If I recall correctly, I wrote this headline myself. And I totally stand by it. If you think I wrote this just to "get attention" you didn't understand my reasoning. You may want to have a look at this for context (I wrote this under a pseudonym)

Beyond Math 

by Sophia Magnusdottir

https://fqxi.org/data/essay-contest-files/Magnusdottir_fqxi15.pdf

@philipthrift 

[Bruce Kellett]

This is just an argument from authority, Phil. And one can always find other authorities with different views.

Bruce 

 

[Lawrence Crowell]

On Tuesday, June 11, 2019 at 2:09:41 PM UTC-5, Philip Thrift wrote:

On Tuesday, June 11, 2019 at 12:27:07 PM UTC-5, Lawrence Crowell wrote:

On Tuesday, June 11, 2019 at 7:13:55 AM UTC-5, Philip Thrift wrote:

On Tuesday, June 11, 2019 at 6:38:41 AM UTC-5, Lawrence Crowell wrote:

...

This trend has galloped off into some sort of nonsense. Some of these people are fairly well known, such as Dowkers, Wharton, Sorkin and Deutsch, but they have all gone into some sort of fantasy land. It is too bad in a way that Bohr is not still alive to shake his finger at these folks. It appears that in some ways this is a case of Alan Ginsburg's Howl, with "I have seen the best minds of this generation go mad." These ideas are so patently wrong, that with a fairly basic even minimal argument based on plain vanilla QM they can be seen as false.

LC

 

So Fay Dowker and Rafael Sorkin 

   https://en.wikipedia.org/wiki/Fay_Dowker

   https://en.wikipedia.org/wiki/Rafael_Sorkin

are now in fantasy land. 

You want to turn physics into a religious fundamentalist cult.

@philipthrift

Sorry, but there are trends in academia where people by virtue of their position are able to promote nonsense. I think Jonathan Swift had a bit to say with the the floating island of Laputia, which was a knock on academia. 

The problem with Dowker and her path integral ideas is the path integral is a math method; it has no additional physical content. In fact in general in the way it is written it has less content because it is expanded around a classical extremum. QFT is much the same. QFT sets commutators of observables with spacelike separations to zero, when quantum mechanics in its pure setting tells us there is nonlocality and this condition is an auxiliary postulate meant to ease calculations. String theory has some "funnies" to it as well. The interesting thing about the holographic principle with black holes is it tells us that quantum fields are projections from fields near the horizon where Lorentz symmetry has these quantum field in a time dilated and nonrelativistic QM form. In effect plain vanilla QM, the stuff in Merzbacher or Cohen-Tannoudji etc is really the fundamental stuff. 

Along these lines with fundamental physics, with exceptional group theory, Leech lattice, and Jordan algebras etc, the theta representation of these involve equations that in complex form are Schrodinger equations. In a Euclideanized form they are heat equations with heat kernel solutions. When applied to the integral representation of qubits on a stretched horizon it does suggest that in some fancy way, say with relationships between entanglements, causality and spacetime, the most fundamental theory of the universe is just plain QM. 

I would strongly advise anyone to avoid ideas about hidden variables or in this case ideas of advanced potentials that in ways "wire up" the appearance of nonlocality with local rules. For various reasons these ideas are not consistent with QM, and at the end of it all these ideas do not produce QM as some derived result, but rather demolish it. 

LC

So Dowker (professor of theoretical physics at Imperial College London) is misguided and you are not. Who are you?

The main idea of "Lost in Math" (Sabine Hossenfelder) addresses the fundamentalist mindset expressed above that traps many (she would know more how many, being around them) physicists.

Actually Sabine's argument is about people in positions at schools spinning off nonsense. I have actually read her book.

LC

[Philip Thrift]

So then you are also OK with (which expresses the philosophy underlying the book)

The End of Theoretical Physics As We Know It

by Sabine Hossenfelder

https://www.quantamagazine.org/the-end-of-theoretical-physics-as-we-know-it-20180827/

Beyond Math 

by Sophia Magnusdottir (actuailly Sabine Hossenfelder)

https://fqxi.org/data/essay-contest-files/Magnusdottir_fqxi15.pdf

@philipthrift 

[Lawrence Crowell]

I worked out recently a MATHEMATICA solution to a differential equation. The amount of time it would have taken me to do this by analysis would have been 10s of times longer. We are in the age of numerical applications. I suppose I see nothing particularly wrong with that. In the theory of differential equations, since the time of Frobenius et al say a century ago progress has gone into a bit of a crawl. There have been developments with systems of differential forms and Pfaffians with nonlinear DEs, but this is formidable.

LC

[Bruno Marchal]

On 11 Jun 2019, at 08:14, Bruce Kellett <bhkel...@gmail.com> wrote:

On Tue, Jun 11, 2019 at 3:53 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 10 Jun 2019, at 08:54, Bruce Kellett <bhkel...@gmail.com> wrote:

 

On Mon, Jun 10, 2019 at 4:34 PM Philip Thrift <cloud...@gmail.com> wrote:

Retrocausal hidden variable models are completely compatible with experiments, unless QM itself is wrong.

If retrocausality is right, then QM itself is certainly wrong. In the EPR situation, the singlet state is rotationally symmetric in standard QM, and this cannot be the case if that state is dependent on the future polariser settings. Conversely, if QM is right, retrocausality is impossible.

If QM with collapse is right, I would understand and agree. That is why Deutsch see the “retrocausality” has a semantic variant of the many-worlds interpretations, but I have not entirely figure out if this makes sense

It makes no sense at all! Deutsch has gone completely off the rails over quantum mechanics. He is essentially abandoning the theory as it currently stands. The argument from symmetry is, to my mind, a total killer of any retrocausal explanation -- retrocausality must destroy the very symmetry that is at the heart of the QM predictions for the singlet state, Collapse and many worlds are all irrelevant to this argument.

It would be nice if you could elaborate on this.

The non-locality of the quantum singlet state is irreducible, and neither retrocausality nor many worlds has any impact on this central conclusion.

We have discussed this, and we have agree to disagree on how the MW interpret the quantum state.

Personally, I consider that QM is local and deterministic in any third person view of the multi-histoires, and that indeterminacy, and non locality comes from our distribution in the wave, or, actually, in arithmetic. Technically, there are evidences that the physical reality is non local, but not yet a definite proof of this, as the material modes of self-reference are untractactable on this. 

Non locality is an open problem, with in physics and in philosophy of mind, I would say.

Bruno 

Bruce

 

in the Omnes-Griffith-Gelman-Hartle view of the many-worlds. That would be nice and eliminate t’hooft’s need of “super-determinism” (mechanism is trivially "super-deterministic" in the third person view, but not at all in the first person views—that plays a role for free-will/self-determination). 

Bruno

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[Bruce Kellett]

On Thu, Jun 13, 2019 at 11:23 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 11 Jun 2019, at 08:14, Bruce Kellett <bhkel...@gmail.com> wrote:

 

On Tue, Jun 11, 2019 at 3:53 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 10 Jun 2019, at 08:54, Bruce Kellett <bhkel...@gmail.com> wrote:

If retrocausality is right, then QM itself is certainly wrong. In the EPR situation, the singlet state is rotationally symmetric in standard QM, and this cannot be the case if that state is dependent on the future polariser settings. Conversely, if QM is right, retrocausality is impossible.

If QM with collapse is right, I would understand and agree. That is why Deutsch see the “retrocausality” has a semantic variant of the many-worlds interpretations, but I have not entirely figure out if this makes sense

It makes no sense at all! Deutsch has gone completely off the rails over quantum mechanics. He is essentially abandoning the theory as it currently stands. The argument from symmetry is, to my mind, a total killer of any retrocausal explanation -- retrocausality must destroy the very symmetry that is at the heart of the QM predictions for the singlet state, Collapse and many worlds are all irrelevant to this argument.

It would be nice if you could elaborate on this.

The basis of retrocausality is the observation that there is no problem with non-local influences in QM if the initial state is allowed to depend on the final state, namely, on the settings of the polarisers in the EPR experiment. The QM representation of the singlet state is rotationally symmetric (about the propagation axis). This symmetry is central to the derivation of the correlations that violate the Bell inequalities. If the initial state is made to depend on the final polarizer settings, then the rotational symmetry is lost. So the basis for the original correlation predictions is lost, and the theory becomes incoherent.

As it currently stands, the formalism of QM does not allow the singlet state to depend on the final polariser settings, so standard QM is inconsistent with retrocausality.  It might be possible to restore the required rotational symmetry in a wider context (taking the remote polarisers into account), but QM does not do this. Retrocausality is a different theory, it is not QM. And that different theory has not been coherently worked out.

The rotational symmetry of the initial singlet state is independent of whether you have a collapse model, or have Many Worlds. The difference between these two only comes into play when you include the final measurements. So it is the retrocausal model that requires collapse -- retrocausality cannot work coherently in a many worlds setting.

 Bruce

[Lawrence Crowell]

The dependency of the initial and final states means the probabilities are classical and will obey the Bell inequality. This is a pretty iron clad result and I am not sure why some people persist in thinking they can get around it.

LC 

[Brent Meeker]

If you consider a multiverse view in which there are an ensemble of results (whose correlations violate Bell's inequality) and then you just "play the multiverse movie backwards" will not the many multiverse results interfere and re-cohere to produce the singlet state?  The multiverse is non-local and so can violate Bell's inequality.  I agree with Bruce that this doesn't provide a mechanism, but given the time symmetry of Schoedinger's equation I don't see that it's a different theory.

Brent

[Bruce Kellett]

On Fri, Jun 14, 2019 at 11:42 AM 'Brent Meeker' via Everything List <everyth...@googlegroups.com> wrote:

On 6/13/2019 6:32 PM, Lawrence Crowell wrote:

The dependency of the initial and final states means the probabilities are classical and will obey the Bell inequality. This is a pretty iron clad result and I am not sure why some people persist in thinking they can get around it.

If you consider a multiverse view in which there are an ensemble of results (whose correlations violate Bell's inequality)

I don't understand this multiverse picture. If one is using Everett's 'many worlds' picture, then there are only four 'worlds' in the usual model with binary outcomes of the measurements. Playing the movie backwards may well recover the initial state, but that is not a retrocausal mechanism. Playing the movie of a Stern-Gerlach measurement backwards will certain recover the initial state, but that does not mean that one can reverse an actual experiment with a measured result.

and then you just "play the multiverse movie backwards" will not the many multiverse results interfere and re-cohere to produce the singlet state?  The multiverse is non-local and so can violate Bell's inequality.  I agree with Bruce that this doesn't provide a mechanism, but given the time symmetry of Schoedinger's equation I don't see that it's a different theory.

It's not a different theory, but neither is it a retrocausal theory -- the initial state does not depend on the final polariser settings.

Bruce 

[Bruce Kellett]

That would be a useful result because it would put these retrocausal models to rest permanently. But how do you prove this?

The retrocausal argument takes the form given by Price in 1996 ('Time's Arrow and Archimedes' Point, p.246-7). Price notes that all that you need is that the production of the particle pairs is governed by the following constraint: "In those directions G and H (if any) in which the spins are going to be measured, the probability that the particles have opposite spin is cos^2(alpha/2), where alpha is the angle between G and H." Price notes that such a condition explicitly violates Bell's independence assumption.

My problem with this has been that such a condition does not specify any plausible dynamics that could operate in this way. And if there were such a dynamical mechanism, it would violate the rotational symmetry of the singlet state. But I don't see that this would inevitable lead to classical probabilities, and correlations that obey the Bell inequalities. 

Bruce

[Philip Thrift]

On Thursday, June 13, 2019 at 7:20:27 PM UTC-5, Bruce wrote:

As it currently stands, the formalism of QM does not allow the singlet state to depend on the final polariser settings, so standard QM is inconsistent with retrocausality. 

 

 Bruce

There is a "the" formalism of QM? It's "the" one the LORD God wrote into Stone Tablets on Mount Sinai I suppose you are referring to. The one and only. Why are so many physicists strict religious fundamentalists?

I don't see this in:

The Feynman formulation of Quantum Mechanics builds three central ideas from the de Broglie hypothesis into the computation of quantum amplitudes: the probabilistic aspect of nature, superposition, and the classical limit. This is done by making the following three three postulates:

1. Events in nature are probabilistic with predictable probabilities P.
2. The probability P for an event to occur is given by the square of the complex magnitude of a quantum amplitude for the event, Q. The quantum amplitude Q associated with an event is the sum of the amplitudes  associated with every history leading to the event.
3. The quantum amplitude associated with a given history  is the product of the amplitudes  associated with each fundamental process in the history.

Postulate (1) states the fundamental probabilistic nature of our world, and opens the way for computing these probabilities.

Postulate (2) specifies how probabilities are to be computed. This item builds the concept of superposition, and thus the possibility of quantum interference, directly into the formulation. Specifying that the probability for an event is given as the magnitude-squared of a sum made from complex numbers, allows for negative, positive and intermediate interference effects. This part of the formulation thus builds the description of experiments such as the two-slit experiment directly into the formulation. A history is a sequence of fundamental processes leading to the the event in question. We now have an explicit formulation for calculating the probabilities for events in terms of the  , quantum amplitudes for individual histories, which the third postulate will now specify.

Postulate (3) specifies the quantum amplitude associated with individual histories in terms of fundamental processes. A fundamental process is any process which cannot be interrupted by another fundamental process. The fundamental processes are thus indivisible ``atomic units'' of history. With this constraint of the choice of fundamental processes, individual histories may always be divided unambiguously into ordered sequences of fundamental events, which is key to making a consistent prescription for computing the amplitudes of individual histories from fundamental processes. The fact that the definition of fundamental processes is not very specific is actually one of the strongest aspects of the Feynman approach. As we will see, we may sometimes discover that we may lump fundamental processes together into larger units which make up new fundamental processes. This procedure is know as renormalization and is one the the great central ideas in managing the infinities in quantum field theory.

The third postulate builds in the classical limit by allowing recovery of the classical physics notion that the probability of an independent sequence of events is the product of the probabilities for each event in the sequence. If we know the sequence of fundamental processes leading to an event, the only contributing history is that sequence of processes. In such a case, we have so that then  , where the  are just the probabilities for the individual processes in the sequence, and we recover the usual classical probabilistic result.

What remains unspecified by these postulates is the specification of a valid set of fundamental processes and corresponding quantum amplitudes  for the phenomena we wish to describe. For this information, we must rely upon experimental observations. It is at this point that experimental information is input into the Feynman formulation much like how we inputted experimental information into our formulation when we produced the forms for our operators and the Schrödinger Equations.

A great appeal to the Feynman sum over histories approach is that often we are able to intuit the nature and amplitudes of the fundamental events. A natural way to build the de Broglie hypothesis  from the Davisson-Germer and G.P. Thomson experiments into the formulation, for instance, would be to ascribe a quantum amplitude of  for the propagation of a particle with momentum  across a distance a.

Another common way to infer the fundamental events and associated amplitudes is to determine the amplitudes for fundamental processes from the requirement that the Feynman formulation always give the same results as an already established approach, such as Schrödinger formulation. This latter procedure is referred as construction of Feynman rules, and is also how we determine that the Feynman approach is indeed equivalent to the other formulations of quantum mechanics. We shall follow this procedure in the next section.

...

http://muchomas.lassp.cornell.edu/8.04/Lecs/lec_FeynmanDiagrams/node3.html

 @philipthrift

[Bruce Kellett]

On Fri, Jun 14, 2019 at 4:33 PM Philip Thrift <cloud...@gmail.com> wrote:

On Thursday, June 13, 2019 at 7:20:27 PM UTC-5, Bruce wrote:

As it currently stands, the formalism of QM does not allow the singlet state to depend on the final polariser settings, so standard QM is inconsistent with retrocausality. 

 

 Bruce

There is a "the" formalism of QM? It's "the" one the LORD God wrote into Stone Tablets on Mount Sinai I suppose you are referring to. The one and only. Why are so many physicists strict religious fundamentalists?

I don't see this in:

It's in there if you know how to look! Histories lead from the past to the future -- that is how amplitudes are calculated. This explicitly rules out retrocausality.

Bruce 

[Philip Thrift]

But the reflective path integral is consistent with the path integral; there are both futures and histories. So it's consistent with, not ruled out.

@philipthrift

@philipthrift

[Bruce Kellett]

On Fri, Jun 14, 2019 at 5:36 PM Philip Thrift <cloud...@gmail.com> wrote:

On Friday, June 14, 2019 at 2:00:01 AM UTC-5, Bruce wrote:

On Fri, Jun 14, 2019 at 4:33 PM Philip Thrift <cloud...@gmail.com> wrote:

On Thursday, June 13, 2019 at 7:20:27 PM UTC-5, Bruce wrote:

As it currently stands, the formalism of QM does not allow the singlet state to depend on the final polariser settings, so standard QM is inconsistent with retrocausality. 

 

 Bruce

There is a "the" formalism of QM? It's "the" one the LORD God wrote into Stone Tablets on Mount Sinai I suppose you are referring to. The one and only. Why are so many physicists strict religious fundamentalists?

I don't see this in:

It's in there if you know how to look! Histories lead from the past to the future -- that is how amplitudes are calculated. This explicitly rules out retrocausality.

Bruce 

But the reflective path integral is consistent with the path integral;

No it is not. It it gives a different answer for the same physical situation, so it can't be consistent.

 

there are both futures and histories. So it's consistent with, not ruled out.

It is inconsistent with standard quantum mechanics, in any formalism. So in so far as QM is correct, retrocausality is ruled out -- it is a different theory.

Incidentally, how would you write down the amplitude for the singlet state made up of two spin half particles?

Bruce 

[Philip Thrift]

You just write down a pair: a state and its CPT-mirror state.

@philipthrift

[Bruce Kellett]

OK. You do that and show how it depends on the future polarizer settings in a way that gives comprehensible dynamics.

Bruce

[Philip Thrift]

I did for The EPR experiment

https://codicalist.wordpress.com/2018/03/16/mirror-mirror/

@philipthrift

[Bruce Kellett]

Price's Ypiaria is not quantum mechanics, and no quantum dynamics are specified. Besides, do it here and don't just post links to incomprehensible notes or references to books.

If you make up your own dynamics, you can presumably get any results you want. But the singlet state is well-defined quantum mechanically, and it is that state that is to give the EPR correlations. I think the problem that you are going to face with any attempt at a retrocausal explanation is that the singlet state is independent of the way in which it was formed. But for retrocausality to work, the initial state must depend on things in the future -- i.e., the state must depend on the way in which it is formed. This is not achievable by simply adding the CPT mirror state.

So you have yet to answer the crucial question.

Bruce

[Philip Thrift]

The EPR experiment

There is a source S that simultaneously emits two particles a and b that travel from emitter S to detectors A (in one direction) and B (in the opposite direction) respectively. (See picture.) In the orange world, there are the counterparts to S, A, B: -S, -A, -B. There are not two, but four RFPs to consider: path(a), path(-a), path(b), path(-b). path(a) and path(b) are in our time perspective, path(-a) and path(-b) in the CPT-reversed perspective: Orange particles going from -A and -B arrive at -S at the same time. (In the orange world, -a and -b are absorbed by -S.)

a and -a (and b and -b) never “meet”. They just share hidden (logical) variables.

Note: “Bell’s Theorem requires the assumption that hidden variables are independent of future measurement settings.” – Backward causation, hidden variables and the meaning of completeness, Huw Price. But this assumption is ruled out here, so particles will have hidden variables.

The example used here is from Huw Price’s Time’s Arrow and Archimedes’ Point: New Directions for the Physics of Time (beginning pg. 213) about what happens on a planet called Ypiaria (“Pronounced, of course, ‘E-P-aria’.”)

The scenario here is that there is a pair of twins a and b who depart from S and travel to A and B respectively. At each place A and B, there is an interrogator who asks them respectively a question.

One question only could be asked, to be chosen at random from a list of three:
(1) Are you a murderer?
(2) Are you a thief?
(3) Have you committed adultery?

 

The assumption is that each twin is truthful. The interrogators recorded all questionings of all twin pairs.

The records came to be analyzed by the psychologist Alexander Graham Doppelganger.

He found that
(D-1) When each member of a pair of twins was asked the same question, both always gave the same answer; and that
(D-2) When each member of a pair of twins was asked a different question, they gave the same answer on close to 25 percent of such occasions.

It may not be immediately apparent that these results are in any way incompatible.

 

What follows in Price’s Ypiaria story is how Doppelganger reasoned this out. (This is related to statistics to a real EPR experiment.) Below is how it could work out in a Reflective Path Integral (RPI) formulation.

Let S(1) = ‘Y’ or ‘N’, S(2) = ‘Y’ or ‘N’, S(3) = ‘Y’ or ‘N’ (corresponding to “Yes” or “No” responses).

a with hidden variables (_S1,_S2,_S3):_Qa is sent from S to A; b with hidden variables (_S1,_S2,_S3):_Qb is sent from S to B. This is represented as two paths:

path(a,(_S1,_S2,_S3):_Qa)
path(b,(_S1,_S2,_S3):_Qb)

 

From here on, ‘state’ will be used for ‘hidden variables’ as they become unified with concrete (ground term) values.

At -A: σ_unify(_Qa, {1/.333..,2/.333..,3/.333..})
At -B: σ_unify(_Qb, {1/.333..,2/.333..,3/.333..})

-a with state (_S1,_S2,_S3):_Qa = antiparticle returned from -A in reverse time, -b with state (_S1,_S2,_S3):_Qb = antiparticle returned from -B in reverse time.

path(-a,(_S1,_S2,_S3):_Qa)
path(-b,(_S1,_S2,_S3):_Qb)

 

_Qa, _Qb each are bound to 1,2,or 3. Let Aq = _Qa, Bq = _Qb. (_Qa and _Qb are ground terms.)

In the the orange world, -a and -b are absorbed by -S. This stochastically influences the distribution of (S(1),S(2),S(3)):_ in the blue world, as follows.

Assign probabilities to each possibility:

prob( (S(1),S(2),S(3),Aq,Bq) )

 

There are 2*2*2*3*3 = 72 possibilities. Let P be this set.

Let

Q = { (S(1),S(2),S(3),Aq,Bq) | Aq != Bq, S(Aq) = S(Bq) }

 

It turns out that Q represents 24 of the 72 possibilities in P.

prob( (S(1),S(2),S(3),qA,qB) ) is defined such that

prob(Q) = .25 (should be .333… if all possibilities are equally likely)

 

It turns out that the probability to be assigned to each of the members of the Q sum is about .01, and the all the other possibilities about .0158.

Define a distribution D over P with elements assigned these probabilities.

Then σ_unify( (_S1,_S2,_S3, qA, qB), D).

This selects S(1),S(2),S(3) in the blue world.

 

 

The EPR experiment can then be written as 7 σCP processes:

path(a,(_S1,_S2,_S3):_Qa)
path(b,(_S1,_S2,_S3):_Qb)
σ_unify(_Qa, {1/.333..,2/.333..,3/.333..})
σ_unify(_Qb, {1/.333..,2/.333..,3/.333..})
path(-a,(_S1,_S2,_S3):_Qa?)
path(-b,(_S1,_S2,_S3):_Qb?)
σ_unify((_S1,_S2,_S3,_Qa?,Qb?), D)

Note: This example is updated in σCP – Stochastic Concurrent Prolog.

σCP – Stochastic Concurrent Prolog

 

a preliminary specification

 

σCP is defined more formally here, updating and revising its preliminary definition in Mirror, mirror.

The syntax and terminology follows that presented in

The Family of Concurrent Logic Programming Languages
Ehud Shapiro
ACM Computing Surveys, Vol. 21, No. 3, September 1989
[pdf] [pdf-a]

 

cf. [Wikipedia:Concurrent_logic_programming]

There is one major change from the “Edinburgh syntax” defined in the above paper (which will be referred to as CLPL): All logical variables in σCP must begin with an underscore (‘_’). So _X is a logical variable, but X is a function symbol or predicate. As usual, _ by itself is the anonymous logical variable.

With that notational change, σCP begins with the language FCP(?) [section 3.8, CLPL]. “FCP(?) assumes two types of variables, writable (ordinary) variables and read-only variables, and uses read-only unification, which is an extension of ordinary unification, to unify terms containing read-only variables.”

FCP stands for “Flat Concurrent Prolog”: “In a flat language, a process can perform only a simple computation, specified by a conjunction of atoms with primitive predicates, before making a committed nondeterministic choice” [Introduction, CLPL]. σCP is a flat language. (The possibility of extending σCP to include FCP(:,?) [section 3.9, CLPL] is a possibility. In that case the language would be referred to as σCP(:), since ? is already included in σCP.)

Where σCP extends the syntax of FCP(?) is by the introduction of assigning probabilities [cf. Stochastic Prolog] to clauses:

A :- G | P / B.

 

where P is a number or a read-only variable.

The read-only variable, like _P?. is assumed to have the value of a number if that clause is selected.

The semantics of stochastic clauses is as follows: Given a goal A, the set of clauses that can reduce A is { A1 :- G1 | p1 / B1, A2 :- G2 | p2 / B2, …}. The ps are the numbers or read-only variables that have achieved a numerical value. (The goal cannot be reduced until all clauses for the A predicate have a probability assignment.) They act as weights: A clause is selected stochastically – after the head A and guard G succeed for that clause – based on the weights: sum the weights and normalize to get a probability). (in the case where the ‘/’ symbol is not there, assume that that clause gets assigned the maximum weight of the other clauses. If there is no ‘/’ for any clause that predicate, assume equal probabilities.)

Builtins: uniform(_X) unifies _X with a value in [0.0,1.0] with uniform distribution. boolean(_X) unifies _X with 0 or 1 with equal distribution.

 

Example

From Mirror, mirror, assigning probabilities to the hidden variables (states) in the Ypiaria example:

yes_or_no(Y).
yes_or_no(N).

% This is equivalent to
%     yes_or_no(Y) :- 0.5 / true.
%     yes_or_no(N) :- 0.5 / true.

genes(_S1,_S2,_S3) :- yes_or_no(_S1), yes_or_no(_S2), yes_or_no(_S2).

question(1).
question(2).
question(3).

% A query question(_Q) binds _Q to 1, 2, or 3 with equal probability.

prob(_S,_S,_,1,2) :- 0.01 / true.
prob(_S,_,_S,1,3) :- 0.01 / true.
prob(_S,_S,_,2,1) :- 0.01 / true.
prob(_,_S,_S,2,3) :- 0.01 / true.
prob(_S,_,_S,3,1) :- 0.01 / true.
prob(_,_S,_S,3,2) :- 0.01 / true.
prob(_,_S2,_S3,1,1) :- _S2 != _S3 | 0.0158 / true.
prob(_S1,_,_S3,2,2) :- _S1 != _S3 | 0.0158 / true.
prob(_S1,_S2,_,3,3) :- _S1 != _S2 | 0.0158 / true.

state(_S1,_S2,_S3,_Aq,_Bq) :- 
   genes(_S1,_S2,_S2), 
   question(_Aq), question(_Bq), 
   prob(_S1?,_S2?,_S3?,_Aq?,_Bq?).

 

 

σCP has the following dynamic features:

The syntax { term1, term2, … } constructs a bundle of terms (like a set). Bundle is a builtin datatype.

There are the basic predicates for creating bundles:
1. add(_Term,_Bundle,_NewBundle)
2. remove(_Term,_Bundle,_NewBundle)
3. get(_Bundle,_N,_Term)

σCP becomes dynamic with these predicates:
1. assert(_BundleOfClauses, _Asserted)
2. retract(_BundleOfClauses, _Retracted)
3. spawn(_BundleOfTerms,_Completed)

Spawns a swarm of processes from a bundle of terms.

 

 

A clause is a term of the form

(Head :- Guard | Probability* / Body)

 

* a number or a read-only variable

_Asserted is bound to true when all assertions are completed. Likewise for _Retracted. _Completed is bound to true when all terms (spawed as processes are finished.

The builtin makeID(_ID) makes a new identifier.

 

Define σ_unify (from Mirror, mirror) in σCP:

Let D = { x[1]/p[1], …, x[n]/p[n] }. A bundle B of clauses is created via a σCP predicate

dist2clauses(_ID, _D,_B)

 

with terms

(outcome(_ID, x[i]) :- p[i] / true)

 

_ID is a unique identifier. Define

σ_unify (_X,_ID,_C?) :- outcome(_ID?,_X).

 

Then when processes makeID(_ID), dist2clauses(_ID?,_D,_B), assert(_B,_C) have run, any goal σ_unify (_X,_ID,_C) will bind _X to a random element of D.

More examples coming … (including the path_integral).

Now at A σCP formulation of the path integral.

In the σCP / Reflective Path Integral formulation, stochastic unification (σ-unify) – selecting one clause from a bundle of clauses -corresponds to “wave-function collapse”.

@philipthrift 

[Bruce Kellett]

The incomprehensible jumble that follows bears no relation to the EPR experiment with entangled particles in the singlet state. As I said, if you make up your own arbitrary dynamics, of course retrocausality can result in non-classical correlations. But you have to do this with real physics, not made up worlds.

Bruce

 

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[Philip Thrift]

On Friday, June 14, 2019 at 6:21:04 AM UTC-5, Bruce wrote:

On Fri, Jun 14, 2019 at 7:23 PM Philip Thrift <cloud...@gmail.com> wrote:

https://codicalist.wordpress.com/2018/03/16/mirror-mirror/

The incomprehensible jumble that follows bears no relation to the EPR experiment with entangled particles in the singlet state. As I said, if you make up your own arbitrary dynamics, of course retrocausality can result in non-classical correlations. But you have to do this with real physics, not made up worlds.

Bruce

That's very quaint, but as Sabine Hossenfelder writes, the future of theoretical physics is in (new kinds of) programming, not (current) mathematics.

https://www.quantamagazine.org/the-end-of-theoretical-physics-as-we-know-it-20180827/

@philipthrift

[Lawrence Crowell]

I think you are thinking of the MWI, not so much the multiverse. 

Quantum mechanics is time reversal invariant, so rewinding the dynamics is not the issue. The issue is whether there are causal propagations in both directions. In other words we generally think there is a causal direction from past to future. In QFT and the path integral we compute the amplitudes of time ordered fields. We do not though think of there being both forwards and backwards propagators, retarded and advanced gauge potentials and the rest. If there are retarded and advanced potentials, then we can write a potential as a vector sum of these. This would mean a spacelike propagation of information. Thus if you were to say nonlocality is constructed this way it would ultimately mean there is classical information that would obey the Bell inequalities. 

With cosmology things are a bit stranger. For one we really do not know if these other cosmologies or pocket worlds are not just off-shell parts of the amplitude, where there may only be one on shell set of states which is this pocket world. This might be the case if the quantum description is that of a pure state. The multiverses would be real if there is a statistical mixture. Either that or this pocket world is one state in a coherent set of states that would mean all the other pocket cosmologies are identical to this one we observe. Remember, coherent quantum states define a symplectic submanifold in Hilbert space and are "classical-like." 

LC

[John Clark]

On Thu, Jun 13, 2019 at 10:18 PM Bruce Kellett <bhkel...@gmail.com> wrote:

On Fri, Jun 14, 2019 at 11:32 AM Lawrence Crowell <goldenfield...@gmail.com> wrote:

>> The dependency of the initial and final states means the probabilities are classical and will obey the Bell inequality. This is a pretty iron clad result and I am not sure why some people persist in thinking they can get around it.

> That would be a useful result because it would put these retrocausal models to rest permanently. But how do you prove this?

You prove it the same way physicists prove anything, by performing an experiment. It makes no difference if Quantum Mechanics is someday superseded by a better theory, if probabilities are classical it would be logically impossible to ever violate Bell's inequality even in theory, but in actuality it is quite easy to do so, you do it every time you put on polarizing sunglasses.

> The retrocausal argument takes the form given by Price in 1996 ('Time's Arrow and Archimedes' Point, p.246-7). Price notes that all that you need is that the production of the particle pairs is governed by the following constraint: "In those directions G and H (if any) in which the spins are going to be measured, the probability that the particles have opposite spin is cos^2(alpha/2), where alpha is the angle between G and H." Price notes that such a condition explicitly violates Bell's independence assumption.
My problem with this has been that such a condition does not specify any plausible dynamics that could operate in this way.

Since 1809 we've know from experiment that Malus's law always works, that is to say the amount of light polarized at 0 degrees that will make it through a polarizing filter set at X degrees is [COS (x)]^2.  For example if x = 30 DEGREES then the value is .75; if light is made of photons that translates to the probability any individual photon will make it through the filter is 75%. However if ANY local hidden variable theory is true Bell proved that the probability must be less than or equal to 66.666%. But  3/4 is greater than 2/3, so Bell's inequality is violated. So local hidden variables are as dead as a doornail.

John K Clark

[Philip Thrift]

Religious fundamentalism.

@philipthrift 

[Lawrence Crowell]

This is physics and a range of experiments confirm this. The Bell inequality, to take this argument further, with polarizers is if one polarizer is set 30 degrees relative to the other, then think of the photons as polarized in the way a nail has a direction. 30 degrees is a third of a right angle, and so if we think of the photons as being like nails aligned in a certain direction, then at least 1/3rd of these nails would be deflected away. This is why an upper bound of 2/3rds of the photons in a classical setting will make it through, or less will by attenuating effects etc. But the quantum result gives 3/4. This is a violation of the Bell inequality, and with polarizers it is found in a "quantization on the large." Of course sensitive experiments work with one photon at a time, but the same result happens. This is done to insure there are not some other statistical effect at work between photons. 

LC

[Philip Thrift]

Bell's theorem is wrong. If p_hid(X) is the distribution of hidden variables, and p_det(D) is the distribution of detector settings, and p(X,D) is the joint distribution, then it assumes

       p(X,D) = p_hid(X)·p_det(D)

an unwarranted (religious fundamentalist) assumption.

@philipthrift

[Bruce Kellett]

The trouble with your fundamentalist assumption is that it does not work in real physics. You have only to give a plausible dynamical model of how this works for the Aspect experiment, say, and we will accept that you have a point. But you are unable to do this. I would lay long odds on the fact they you will be unable to do it, even given an infinite amount of time and computing power.

Bruce

[Philip Thrift]

People can go though life believing whatever they want.

@philipthrift 

[Bruce Kellett]

I see that you can't do it. Thank you for proving my point.

Bruce 

[Philip Thrift]

I've basically lived my life believing what I want, I think.

I'm not trying to convince anyone of anything. 

One thing I might try to convince people of:

    Physics is fiction.

Vic Stenger would have said "Physics is models".

There are always alternative models, and new ones likely coming in the future.

To find reality in a model (to make truth claims in the vocabulary of a model) is a form of religious fundamentalism.

@philipthrift

[Bruce Kellett]

I've got nothing against models, or against thinking of physics as models. But it does seem to me important that the models actually work. Or else you are in la la land.

Bruce 

[Philip Thrift]

We know the Standard Model doesn't "work".

Physics beyond the Standard Model (BSM) refers to the theoretical developments needed to explain the deficiencies of the Standard Model ...

https://en.wikipedia.org/wiki/Physics_beyond_the_Standard_Model

Physicists seem to conflate "work" and "truth".

@philipthrift

[Bruce Kellett]

On Sat, Jun 15, 2019 at 6:02 PM Philip Thrift <cloud...@gmail.com> wrote:

On Saturday, June 15, 2019 at 2:43:29 AM UTC-5, Bruce wrote:

On Sat, Jun 15, 2019 at 5:29 PM Philip Thrift <cloud...@gmail.com> wrote:

One thing I might try to convince people of:

    Physics is fiction.

Vic Stenger would have said "Physics is models".

There are always alternative models, and new ones likely coming in the future.

To find reality in a model (to make truth claims in the vocabulary of a model) is a form of religious fundamentalism.

I've got nothing against models, or against thinking of physics as models. But it does seem to me important that the models actually work. Or else you are in la la land.

Bruce 

We know the Standard Model doesn't "work".

That will be news to the physics community. The thing about the Standard Model is that it does work everywhere that it has been tested within its domain. That does not mean that it is necessarily the last word, but it is just stupid to say that it doesn't work.

 

Physics beyond the Standard Model (BSM) refers to the theoretical developments needed to explain the deficiencies of the Standard Model ...

https://en.wikipedia.org/wiki/Physics_beyond_the_Standard_Model

Physicists seem to conflate "work" and "truth".

That's your misunderstand ing of what physics and models are about.

Bruce 

[Philip Thrift]

Physicists find some model that works somewhere. And then they make make truth statements in the vocabulary ("quantum states", for example) of a model which claims the actual reality (existence) of entities those terms refer to in the vocabulary.

That's what Vic called platonism.

@philipthrift

[Bruce Kellett]

Vic  was wrong if he called that platonism. It is actually what is currently known as scientific realism. I do not go along with this totally, being somewhat more inclined to instumentalism -- the purpose of science is to find models that work.

Anyway, all of this is just your attempt to divert attention from the fact that your retrocausal ideas do not work in real experimental situations.

Bruce

[Philip Thrift]

On Saturday, June 15, 2019 at 4:30:51 AM UTC-5, Bruce wrote:

Anyway, all of this is just your attempt to divert attention from the fact that your retrocausal ideas do not work in real experimental situations.

Bruce

I don't think so.

Physicists provide support for retrocausal quantum theory, in which the future influences the past

https://phys.org/news/2017-07-physicists-retrocausal-quantum-theory-future.html

Can the future influence the past? The scientific case for quantum retrocausality

https://boingboing.net/2018/06/15/can-the-future-influence-the-p.html

This Quantum Theory Claims Future Events Can Influence Past Events

https://wallstreetpit.com/113788-quantum-theory-claims-future-events-can-influence-past-events/

...

And then there’s retrocausality, which basically says that the present (or the future) can influence the past, and in terms of cause-and effect, the effect happens prior to the cause. Connecting that concept with quantum entanglement, it’s like saying that measuring an entangled particle in the present (or future) affects the particle’s properties in the past. And instead of the famous Bell tests showing proof of quantum entanglement, they can be regarded as evidence of retrocausality. This is what Matthew S. Leifer of California’s Chapman University and Matthew F. Pusey of Ontario’s Perimeter Institute for Theoretical Physics are proposing.

In relation to the traditional concept of time symmetry which says that physical processes can run forward and backward in time while following the same physical laws, Leifer and Pusey argue that retrocausality should also hold true. They believe that unless we are somehow able to prove that time only moves one way, which is forward, then retrocausal influences should also be considered.

Right now, separate particles seemingly being affected by measuring either of the particles is attributed to the concept of ‘spooky action at a distance’, because there’s simply no other way to explain how the particles influence each other. Leifer and Pusey’s theory is that the measurement of one particle can retrocausally influence the behavior of the other particle. There’s no spooky action at a distance, just retrocausal influence.

While the concept of retrocausality has yet to gain momentum, there are those who believe that it is worth looking further into. And part of its appeal has to do with its breaking away from ‘realist interpretations of quantum theory’ and its implication that it’s time to come up with new alternative interpretations about quantum physics.

As Leifer explained to Phys.org: “I think that different interpretations [of quantum theory] have different implications for how we might go about generalizing standard quantum theory. This might be needed to construct the correct theory of quantum gravity, or even to resolve some issues in high-energy physics given that the unification of the other three forces is still up in the air in the light of LHC results.”

In a way, retrocausality doesn’t make things any clearer. In fact, it might even be making things even weirder. But the point is, it provides an alternative explanation to those ‘entangled particles’. Testing and proving that it’s the correct explanation is the bigger challenge.

The paper detailing Leifer and Pusey’s work was recently published in the journal Proceedings of the Royal Society A.

and so on.

@philipthrift 

[Bruce Kellett]

More arguments from authority. But these are just speculative proposals. If you have an actual retrocausal account of the Aspect experiment, why not produce it? Your contiinued evasions only go to prove that you are just blowing wind.

Bruce

[Philip Thrift]

You write an article that is published in the Royal Society Proceedings responding to the paper

https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.2016.0607 

by Matthew S. Leifer and Matthew F. Pusey 

We conclude that the most plausible response to our result, other than giving up Realism, is to posit that there might be retrocausality in nature. At the very least, this is a concrete and little explored possibility that holds the promise of evading almost all no-go theorems in the foundations of quantum theory, so it should be investigated further.

and you might have some credibility. 

Otherwise, you sound like a quack with a fascist-like authoritarian stance.

I'm not claiming anything to be settled. You are.

@philipthrift

[John Clark]

On Sat, Jun 15, 2019 at 2:10 AM Philip Thrift <cloud...@gmail.com> wrote:

> Bell's theorem is wrong.

Well yes but that's the point! We know from experiment that Bell's Inequality is indeed wrong, but to derive it Bell made only 2 assumptions:

1)High school algebra and trigonometry are correct
2)  Photons have hidden variables.

"Hidden variable"  means there is something different about a particular photon that we just don't know about, something equivalent to a lookup table inside the photon that for one reason or another we are unable to access but the photon can when it wants to know how to behave. But with 

existing technology I can make a real physical machine that violates Bells's inequality. 

So either high school algebra and trigonometry is wrong or the 

hidden variable idea is. Even if Quantum Mechanics is someday proven to be untrue Bell's argument is still valid, in fact his original paper had no Quantum Mechanics in it; his point was that any successful theory about how the world works must explain why his inequality is violated, and today we know for a fact from experiments that it is indeed violated. Nature just refuses to be sensible and doesn't work the way you'd think it should.

OK on to making my machine. I have a black box, it has a red light and a blue light on it, it also has a rotary switch with 6 connections at the 12, 2, 4, 6, 8 and 10 o'clock positions. The red and blue light blink in a manner that passes all known tests for being completely random, this is true regardless of what position the rotary switch is in. Such a box could be made and still be completely deterministic by just pre-computing 6 different random sequences and recording them as a lookup table in the box. Now the box would know which light to flash.

I have another black box. When both boxes have the same setting on their rotary switch they both produce the same random sequence of light flashes. This would also be easy to reproduce in a classical physics world, just record the same 6 random sequences in both boxes.

The set of boxes has another property, if the switches on the 2 boxes are set to opposite positions, 12 and 6 o'clock for example, then there is a total negative correlation; when one flashes red the other box flashes blue and when one box flashes blue the other flashes red. This just makes it all the easier to make the boxes because now you only need to pre-calculate 3 random sequences, then just change every 1 to 0 and every 0 to 1 to get the other 3 sequences and record all 6 in both boxes.

The boxes have one more feature that makes things very interesting, if the rotary switch on a box is one notch different from the setting on the other box then the sequence of light flashes will on average be different 1 time in 4. How on Earth could I make the boxes behave like that? Well, I could change on average one entry in 4 of the 12 o'clock look-up table (hidden variable) sequence and make that the 2 o'clock table. Then change 1 in 4 of the 2 o'clock and make that the 4 o'clock, and change 1 in 4 of the 4 o'clock and make that the 6 o'clock. So now the light flashes on the box set at 2 o'clock is different from the box set at 12 o'clock on average by 1 flash in 4. The box set at 4 o'clock differs from the one set at 12 by 2 flashes in 4, and the one set at 6 differs from the one set at 12 by 3 flashes in 4.

But I said before that boxes with opposite settings should have a 100% anti-correlation, the flashes on the box set at 12 o'clock should differ from the box set at 6 o'clock by 4 flashes in 4 NOT 3 flashes in 4. Thus if the boxes work by hidden variables then when one is set to 12 o'clock and the other to 2 there MUST be a 2/3 correlation, at 4 a 1/3 correlation, and of course at 6 no correlation at all.  A correlation greater than 2/3, such as 3/4, for adjacent settings produces paradoxes, at least it would if you expected everything to work mechanistically because of some

local

 hidden variable involved. 

Does this mean it's impossible to make two boxes that have those specifications? Nope, but it does mean hidden variables can not be involved and that means something very weird is going on. Actually it would be quite easy to make a couple of boxes that behave like that; easy to make and easy to demonstrate that they work, but not easy to understand why they work.

Photons behave in just this spooky manner, so to make the boxes all you need is 4 things:

1) A glorified light bulb, something that will make two photons of unspecified but identical polarization moving in opposite directions so you can send one to each box. An excited calcium atom would do the trick, or you could turn a green photon into two identical lower energy red photons with a crystal of potassium dihydrogen phosphate.

2) A light detector sensitive enough to observe just one photon. Incidentally the human eye is not quite good enough to do that but frogs can, for frogs when light gets very weak it must stop getting dimmer and appear to flash. 

3) A polarizing filter, 

a good pair of sunglasses would do.

4) Some gears and pulleys so that each time the rotary switch is advanced one position the filter is rotated by 30 degrees. This is because as I said before  the amount of light polarized at 0 degrees that will make it through a polarizing filter set at X degrees is [COS (x)]^2;  so if x = 30 DEGREES then the value is .75, so the probability any individual 0 degree photon will make it through that filter is 75%.

The bottom line of all this is that there can not be something special about a specific photon, some internal difference, some hidden variable that determines if it makes it through a filter or not. Thus, assuming high school algebra and trigonometry are correct, one of two things must be true:

1) 

The universe is

 not realistic, that is to say nothing exists until it is observed.

2) There are no hidden variables, no secret deterministic lookup table that tells quantum particles how to behave.

I can't prove it but I have a hunch the moon still exists when I'm not looking at it so I think the second one is the one that is true.

John K Clark

[Bruce Kellett]

It would seem that this paper is just like the others you have cited: it doesn't actually specify a dynamical mechanism for retrocausality, it just claims that if there were such a mechanism, EPR results could be explained thereby.

Not really good enough, Phil. Your sarcasm does you no credit. All you have to do is come up with the dynamics of the retrocausal mechanism that explains the Aspect experiments. But you can't do that, can you? Because, if you could, it would be out there by now, and you would be only too happy to produce the details.

You are condemned as a charlatan by your silence on the important issue.

Bruce

[Lawrence Crowell]

This is not about beliefs. The nonlocal aspects of QM are verified with many experiments that have been repeated. The Aspect experiment of the 80s was a cornerstone on a verification of Bell's theorem. This is what nature does, and what nature "IS" is what nature "DOES." 

LC 

[Lawrence Crowell]

On Saturday, June 15, 2019 at 4:49:55 AM UTC-5, Philip Thrift wrote:

On Saturday, June 15, 2019 at 4:30:51 AM UTC-5, Bruce wrote:

Anyway, all of this is just your attempt to divert attention from the fact that your retrocausal ideas do not work in real experimental situations.

Bruce

I don't think so.

Physicists provide support for retrocausal quantum theory, in which the future influences the past

https://phys.org/news/2017-07-physicists-retrocausal-quantum-theory-future.html

Unfortunately this article is a bit embarrassing. This apparent retrocausality is a nonlocal aspect of QM with respect to time. QM really has fundamentally no description in space or time; it is the up to the analyst or experimenter to represent quantum states in space and time. The Wheeler-Dewitt experiment is a case of this, but to remain within the quantum paradigm means the no-signalling theorem holds. The Kochen-Specker theorem corollary means there is not information transfer involved, which means there is no interaction.

LC

[John Clark]

On Sat, Jun 15, 2019 at 9:45 AM Lawrence Crowell <goldenfield...@gmail.com> wrote:

> to remain within the quantum paradigm means the no-signalling theorem holds. The Kochen-Specker theorem corollary means there is not information transfer involved, which means there is no interaction.

But no signaling (no information transfer) does not necessarily mean the same thing as no interaction. If you and I are 10 light years apart and have quantum entangled coins and flip them at the same time we will both produce a sequence of heads and tails that look completely random to both of us. You then get into your spaceship that moves a 99% the speed of light and visit me. After 10 years you arrive and  when we compare notes we discover that we both produced the exact same (apparently) random sequence. No information was transfered faster than light so you can't use it for communication but an interaction of some sort faster than light must have occurred because we both got the same random sequence at the same time even though we were 10 light years apart; although we couldn't prove the sequences were the same until we communicated and that can only be done at the speed of light or less.  

 John K Clark

[Philip Thrift]

What about

The Cellular Automaton Interpretation of Quantum Mechanics

Gerard 't Hooft

https://arxiv.org/abs/1405.1548

@philipthrift 

[Philip Thrift]

On Saturday, June 15, 2019 at 8:45:05 AM UTC-5, Lawrence Crowell wrote:

Unfortunately this article is a bit embarrassing. ...

Is it the case that when a minority view (I don't know what the majority view is) of physical theory is presented (or is it just some, like retrocausality), the Physics Gestapo is released?

@pphilipthrift 

[Philip Thrift]

On Saturday, June 15, 2019 at 8:20:07 AM UTC-5, Bruce wrote:

. All you have to do is come up with the dynamics of the retrocausal mechanism that explains the Aspect experiments. 

I did: The reflective path integral w/logical variables.

 

You are condemned as a charlatan by your silence on the important issue.

Bruce

 

Of course I'm a charlatan. I've never claimed to be anything else.

What are you?

@philipthrift 

[John Clark]

On Sat, Jun 15, 2019 at 11:19 AM Philip Thrift <cloud...@gmail.com> wrote:

> What about
The Cellular Automaton Interpretation of Quantum Mechanics
Gerard 't Hooft
https://arxiv.org/abs/1405.1548

What about it? Gerard t Hooft is a fan of superdeterminism, it says that out of the infinite number of ways the initial conditions of the universe could have been in it was actually in the only one where things were so hyper precisely arranged 13.8 billion years ago that today we always make exactly precisely the wrong choice whenever we set up our experiments, so we always end up getting fooled and think some things are not deterministic when they really are. That's a lot to swallow. I'm comfortable with the universe being indifferent to us but if superdeterminism is true then it's downright sadistic; although if true we must be mighty damn important if something went to the trouble of setting up the entire universe in the only way that would make fools of beings that would live on a average planet orbiting a average star in a average galaxy in 13.8 billion years.

John K Clark

[Brent Meeker]

On 6/15/2019 12:29 AM, Philip Thrift wrote:

I've basically lived my life believing what I want, I think.

I'm not trying to convince anyone of anything. 

One thing I might try to convince people of:

    Physics is fiction.

Vic Stenger would have said "Physics is models".

There are always alternative models, and new ones likely coming in the future.

To find reality in a model (to make truth claims in the vocabulary of a model) is a form of religious fundamentalism.

You say you're not trying to convince anyone of anything, but you repeatedly slap pejorative labels on other viewpoints.  You use them like Trump uses nick names.  I avoids actually making an argument against them while disparaging them. 

So in this specific instance: Where do you look for reality?  Or do you suppose there is no reality.  If you trained a neural network so that it could produce all the predictions about physics problems that the community of physicists do, would it be just as good as the theories it replaces?

Brent

[Brent Meeker]

On 6/14/2019 11:10 PM, Philip Thrift wrote:
> Bell's theorem is wrong. If p_hid(X) is the distribution of hidden
> variables, and p_det(D) is the distribution of detector settings, and
> p(X,D) is the joint distribution, then it assumes
>
>        p(X,D) = p_hid(X)·p_det(D)
>
> an unwarranted (religious fundamentalist) assumption.

But it's not a mere assumption, it follows from the idea that the hidden
variables take their values at the particle source, while the detector
settings can be independently made space-like relative to the particle
origination.

Brent

[Philip Thrift]

I don't criticize other theories. Any theory anyone want's top pursue is is fine.

It's just the Physics Gestapo I criticize.

@philipthrift

 

[Philip Thrift]

I don't think that "independence" idea can be (absolutely) assumed to be true. 

@philipthrift

[Philip Thrift]

>                                                  Any theory anyone wants to pursue is is fine. 

[smitra]

On 15-06-2019 18:00, John Clark wrote:
> On Sat, Jun 15, 2019 at 11:19 AM Philip Thrift <cloud...@gmail.com>
> wrote:
>
>>> What about

>> _The Cellular Automaton Interpretation of Quantum Mechanics_
>> Gerard 't Hooft
>> https://arxiv.org/abs/1405.1548 [1]

>
> What about it? Gerard t Hooft is a fan of superdeterminism, it says
> that out of the infinite number of ways the initial conditions of the
> universe could have been in it was actually in the only one where
> things were so hyper precisely arranged 13.8 billion years ago that
> today we always make exactly precisely the wrong choice whenever we
> set up our experiments, so we always end up getting fooled and think
> some things are not deterministic when they really are. That's a lot
> to swallow. I'm comfortable with the universe being indifferent to us
> but if superdeterminism is true then it's downright sadistic; although
> if true we must be mighty damn important if something went to the
> trouble of setting up the entire universe in the only way that would
> make fools of beings that would live on a average planet orbiting a
> average star in a average galaxy in 13.8 billion years.
>

't Hooft makes the point that determinism implies superdeterminism. If
we start with a set of low entropy initial states that could have
represented he universe shortly after the Big Bang, then billions of
years later some of these initial states will have evolved into ones
containing human physicist doing experiments. If we then take one such
state where Alice does a measurement with a certain polarizer setting,
and we consider the inverse time evolution of the counterfactual state
where Alice choose a different setting but everything else is kept the
same, then you won't get to a valid low entropy initial state. 't Hooft
argues that this objection makes the counterfactual reasoning in Bell's
theorems invalid.

Saibal

[John Clark]

On Sat, Jun 15, 2019 at 2:33 PM smitra <smi...@zonnet.nl> wrote:

 

>'t Hooft makes the point that determinism implies superdeterminism.

Superdeterminism.implies determinism but not the other way around. Determinism says events can always be predicted from initial conditions but it says nothing about about the initial condition itself. Superdeterminism says out of the astronomically huge number of low entropy stated the universe could have started out in it started out in the only one that would evolve in such a way that after 13.8 billion years human beings that lived of a planet that wouldn't even exist for 9 billion years always made the wrong choices when they set up their quantum reality experiments.

As I said that is a lot to swallow.     

 John K Clark

[Lawrence Crowell]

The interaction which occurred was local in the lab frames of the observers. The interaction did not span 10 light years distance.

LC

[Bruce Kellett]

On Sun, Jun 16, 2019 at 1:42 AM Philip Thrift <cloud...@gmail.com> wrote:

On Saturday, June 15, 2019 at 8:20:07 AM UTC-5, Bruce wrote:

. All you have to do is come up with the dynamics of the retrocausal mechanism that explains the Aspect experiments. 

I did: The reflective path integral w/logical variables.

That is not the Aspect experiment.

 

You are condemned as a charlatan by your silence on the important issue.

Bruce

 

Of course I'm a charlatan. I've never claimed to be anything else.

What are you?

Someone interested in physics......to the exclusion of unevidenced dogma.

Look, Price has been banging on about retrocausal explanations of violations of the Bell inequalities for 30 or more years. And before that, there have been many years of similar ideas, such as Cramer's transactional interpretation and so on. On the surface, these ideas might seem plausible and attractive. But the fact is that even after all this time, they have succeeded in persuading only a few weak-minded individuals. Now why might that be? My explanation is that these ideas have never been applied to give convincing dynamical explanations for anything. In fact, if you try to apply retrocausal ideas to the Aspect experiment, you rapidly run into insuperable difficulties, and are forced to conclude that retrocausality can give only classical correlations -- the result that Lawrence alluded to some time ago.

Bruce

[Lawrence Crowell]

The only thing that can persuade me into thinking there is some classical under-carriage to quantum mechanics is an experimental result. Theoretical arguments or models etc do little for me. Since the dawn of the quantum revolution, say 1927, there have been arguments for hidden variables, retrocausality, tachyons and so forth as a classical substructure that makes sense of Bertelsmann's (if I remember the name right) socks. Nothing has ever come any of this, but meanwhile to nonlocal features of QM have mounting evidence. If an experiment can show that nonlocality is an illusion with some hidden variable etc then after dealing with some cognitive dissonance I will accept that. 

LC

[Brent Meeker]

Bell's theorem allows that his inequality be violated by non-local hidden variables; which is what superdeterminism assumes.

Brent

[Philip Thrift]

On Saturday, June 15, 2019 at 6:06:48 PM UTC-5, Bruce wrote:

On Sun, Jun 16, 2019 at 1:42 AM Philip Thrift <cloud...@gmail.com> wrote:

On Saturday, June 15, 2019 at 8:20:07 AM UTC-5, Bruce wrote:

. All you have to do is come up with the dynamics of the retrocausal mechanism that explains the Aspect experiments. 

I did: The reflective path integral w/logical variables.

That is not the Aspect experiment.

I'll look at it sometime and formulate it in σCP.

Programming (programming languages) is the future of physics.

 

 

You are condemned as a charlatan by your silence on the important issue.

Bruce

 

Of course I'm a charlatan. I've never claimed to be anything else.

What are you?

Someone interested in physics......to the exclusion of unevidenced dogma.

Look, Price has been banging on about retrocausal explanations of violations of the Bell inequalities for 30 or more years. And before that, there have been many years of similar ideas, such as Cramer's transactional interpretation and so on. On the surface, these ideas might seem plausible and attractive. But the fact is that even after all this time, they have succeeded in persuading only a few weak-minded individuals. Now why might that be? My explanation is that these ideas have never been applied to give convincing dynamical explanations for anything. In fact, if you try to apply retrocausal ideas to the Aspect experiment, you rapidly run into insuperable difficulties, and are forced to conclude that retrocausality can give only classical correlations -- the result that Lawrence alluded to some time ago.

Bruce

There are a bunch of people working on both retrocausal and contextual  models, Some are physicists and mathematicians, not just philosophers.

Its an open question (there is nothing closed* in physics).  

ts the Physics Gestapo that wants to swarm in (on what they see as the "weak-minded individuals") and say it is ruled out of bounds.

* https://en.wikipedia.org/wiki/Epistemological_anarchism

@philipthrift

[Philip Thrift]

There are several physicists who adopt Many Worlds.

Why the Many-Worlds Formulation of Quantum Mechanics Is Probably Correct

Posted on June 30, 2014 by Sean Carroll

http://www.preposterousuniverse.com/blog/2014/06/30/why-the-many-worlds-formulation-of-quantum-mechanics-is-probably-correct/

So tell me: Is there an experiment that proves the existence of Many Worlds?

If not, why does the Physics Gestapo descend on the retrocausal people and not the many-worlds people?

@philipthrift

[Philip Thrift]

Bell's Theorem also assumes there is no (stochastic) retrodependency.

@philipthrift