Is action at a distance possible as envisaged by the EPR Paradox.

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The discussion centers on the possibility of action at a distance as proposed by the EPR Paradox, with participants debating the implications of quantum entanglement. It is established that while entanglement has been experimentally demonstrated, it does not allow for faster-than-light communication or signaling. The conversation touches on various interpretations of quantum mechanics, including the Bohmian view and many-worlds interpretation, while emphasizing that Bell's theorem suggests no local hidden variables can account for quantum predictions. Participants express a mix of curiosity and skepticism regarding the implications of these findings, acknowledging the complexities and ongoing debates in the field. Overall, the conversation highlights the intricate relationship between quantum mechanics and the concept of nonlocality.
  • #361
ThomasT said:
My understanding was that qm and hidden variables were assumed to be incompatible due to von Neumann's influence.

That was not completely accepted, although it was certainly influential. Einstein would - in my opinion - have accepted the Bell proof as conclusive had he lived to see it. But he did not accept von Neumann's.
 
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  • #362
ThomasT said:
You have a strange interpretation of scientific and plausible.

Which indicates that you don't understand what either of us is saying. We're advocating certain approaches to different aspects of the EPR-Bell stuff.

Here's a link that explains what I'm saying better that I could:

http://arxiv.org/PS_cache/quant-ph/pdf/0001/0001112v3.pdf

I understand, that you are both borderline crackpots.
 
  • #363
ThomasT said:
Here's a link that explains what I'm saying better that I could:

http://arxiv.org/PS_cache/quant-ph/pdf/0001/0001112v3.pdf

And this is almost like referencing yourself. Basically, the article says: Entanglement is local realistic, proving that entanglement is local realistic.

It isn't that simple. At least De Raedt offered up a formula that leads to a local realistic dataset. Where is the same for this? As I keep pointing out, there is a simple test for any candidate LHV and this one FAILS miserably. Again.
 
  • #364
I thought crackpots were dealt with on this site, I am satisfied that Zonde and ThomasT are that, and offering personal theories.
 
  • #365
my_wan said:
If you get this everything should conceptually click into place.

WOW+WOW+WOW+WOW+WOW!

This is the most intelligent and interesting post I’ve ever read on PF! ABSOLUTELY MIND-BLOWING!

Not only a "click", I almost broke my neck, jumping up & down in my chair! :biggrin:

...I feel dizzy, exhausted...

my_wan said:
Now here's the caveat: If their exist a causal mechanism for indeterminacy, such that it is real, but not fundamental, then EPR correlations prove exactly what Einstein said they prove. It is only through the acceptance of indeterminacy as a "fundamental" property that extra FTL mechanisms are needed to save the fundamental character of indeterminacy.

I get this, and it’s absolutely fantastic and beautiful! There might be a causal mechanism to create the non-causal mechanism we (so far) believe is "ground zero" in QM. And that causal mechanism must look like it’s indeterminate, even if it’s not on fundamental grounds. WOW!

I always loved Einstein, but at the same time I always liked the randomness of the universe – and my free will. It looks like you given me a wonderful solution to this dilemma. Thanks!

(I guess all this is strongly related to "you-know-what"...? :wink:)

my_wan said:
What I find strange here is people searching realistic causal mechanisms (FTL or not) when the very notion of a causal mechanism subverts the justification for needing a causal mechanism to explain EPR. Of course for FTL I guess it could be assumed EPR needs a causal mechanism, but indeterminacy doesn't. But what about the question of whether the wavefunction itself is real. That would directly imply a causal mechanism for indeterminacy, unambiguously subverting the need for a FTL causal mechanism for EPR correlations.

This is very good: We are looking for causal "FTL" mechanism to explain the non-causal mechanism (QM probabilities) in EPR/BTE – where probabilities are the actual proof for EPR/BTE being a true paradox!? That’s a REAL paradox!

To sum up: If "FTL" is not true, then there must be local casual explanation for EPR/BTE, and QM is incomplete (anyway).

(But... wait a minute... if QM and HUP are incomplete? Wouldn’t that mean we could send FTL messages with Quantum teleportation!? Thus meaning FTL is true?? :rolleyes:)

I have shown this video before, but it’s very nice wind up for this wonderful news, where Alain Aspect talks about EPR, Albert Einstein & Niels Bohr and the incompleteness of QM. And when Alain Aspect, in the end of the movie (7:50), says – "You cannot get the wool information of system!" – I suspect that one word could be slightly 'wrong'... :biggrin:

https://www.youtube.com/watch?v=<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/m8P--jFe3vM&hl=en_US&fs=1&rel=0&color1=0x006699&color2=0x54abd6"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/m8P--jFe3vM&hl=en_US&fs=1&rel=0&color1=0x006699&color2=0x54abd6" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>

THANKS!
 
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  • #366
IcedEcliptic said:
I understand, that you are both borderline crackpots.

IcedEcliptic said:
I thought crackpots were dealt with on this site, I am satisfied that Zonde and ThomasT are that, and offering personal theories.
Zonde is arguing that the fair sampling loophole has not been sufficiently closed, which has been an accepted argument, based on accepted scientific methodology, for years. So, he's certainly not being a crackpot. Even though I think that what I'm focusing on sort of moots any loophole argument.

If you don't understand what Zonde's saying, then I wouldn't expect that you would understand what I'm saying either. Read Unnikrishnan's paper that I linked to. Pay attention to the part about an internal nondynamical phase variable imparted at emission.

If you think it's crackpotty to think that correlations between counter-propagating photons emitted during the same atomic transition could possibly be due to their being emitted during the same atomic transition, then, as I mentioned in a previous post, you have a strange interpretation of scientific and plausible.
 
  • #367
DrChinese said:
And this is almost like referencing yourself. Basically, the article says: Entanglement is local realistic, proving that entanglement is local realistic.

It isn't that simple. At least De Raedt offered up a formula that leads to a local realistic dataset. Where is the same for this? As I keep pointing out, there is a simple test for any candidate LHV and this one FAILS miserably. Again.
I think you might have missed the point. Unnikrishnan reproduces the qm predictions with an explicitly local model. Afaik, his result hasn't been refuted.
 
  • #368
ThomasT said:
I think you might have missed the point. Unnikrishnan reproduces the qm predictions with an explicitly local model. Afaik, his result hasn't been refuted.

I just did. You cannot simply SAY it is local realistic. You must demonstrate such. Obviously, this one fails. Otherwise, we would be treated to the solution. You MUST be able to generate a dataset which is realistic.

I am not going to waste my time trying to figure out this gibberish. If you want to use his formula to present a valid set of data, I will look at it. BUT QUIT SAYING IT WITHOUT SHOWING IT!

The entire point of Bell is that he cannot follow through on his claims. I can claim 1=2 too. So what? I can even "prove" it! So please take a minute to understand, we don't want an absurd claim when a dataset can do the trick. Remember: it must have answers for 0/120/240!
 
  • #370
DevilsAvocado said:
(But... wait a minute... if QM and HUP are incomplete? Wouldn’t that mean we could send FTL messages with Quantum teleportation!? Thus meaning FTL is true?? :rolleyes:)

No, because if indeterminacy is not fundamental, then the information producing the correlation can simply be carried by the particles from the original interaction, like the marble analogy. Only the mechanism that carries it must be indeterminate, but not fundamentally so, i.e., a relational ensemble of real (though observer characterized) states. A rabbit is defined by an ensemble of states, such that no two rabbits are precisely the same, or even precisely the same moment to moment, yet they all carry the property "rabbit" wherever they go. Unless they interact with an ensemble with the property called "wolf".

The issue of completeness also has some caveats. If you have a basic computer, and a theory that provides you with the output of every possible input, would that be a complete theory of that computer? In fact it would, even if you had no idea what or how that computer did what it did, or even if there was a computer there. Your "complete" I/O theory would then be an "information theory", not a physical theory. Like RQM defines QM to be, and justifiably labels it complete in that context. The term "complete" carries an entirely different status in that situation, than what is assumed by Einstein realism, which needs to know every part and operation of the physical computer to be labeled complete. The search for hvt's entails finding and dissecting that computer, whether FTL mechanisms are involved or not.
 
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  • #371
ThomasT said:
Zonde is arguing that the fair sampling loophole has not been sufficiently closed, which has been an accepted argument, based on accepted scientific methodology, for years. So, he's certainly not being a crackpot. Even though I think that what I'm focusing on sort of moots any loophole argument.

If you don't understand what Zonde's saying, then I wouldn't expect that you would understand what I'm saying either. Read Unnikrishnan's paper that I linked to. Pay attention to the part about an internal nondynamical phase variable imparted at emission.

If you think it's crackpotty to think that correlations between counter-propagating photons emitted during the same atomic transition could possibly be due to their being emitted during the same atomic transition, then, as I mentioned in a previous post, you have a strange interpretation of scientific and plausible.

I've read that paper, and I believe that Dr. Chinese summed up that tidibt quite well. The issue is not that the formalism if QM is not untenable in some ways, but rather that you are arguing for a loophole that I, along with many others believe has been utterly disprove as a factor. You both argue against something, and grasp at straws to do so, but really your pages of arguments boil down to not liking SQM, and not having a superior theory in its place.

The paper is like your arguments which Dr. Chinese continues to rip to confetti; it is scattered, distracting, and fundamentally lacking in substance. Its only strength is that you have yet to state enough of your position to refute it on purely scientific grounds, but that is yet another weakness. You go on and on about a non-existent loophole, and Zonde has ideas about Malus' Law that are between laughable and upsetting.

Your papers are crocks, you have pages of nonsense and rhetoric, but you continue your circular retreat, and in theory you will keep this up until a mentor finally accepts that you are a genuine crackpot and not just misguided.
 
  • #372
DrChinese said:
That was not completely accepted, although it was certainly influential. Einstein would - in my opinion - have accepted the Bell proof as conclusive had he lived to see it. But he did not accept von Neumann's.
Not sure how you can support that when in fact Einstein's argument required EPR correlations to be real (Bell's inequalities to be violated) as his justification (now empirical) to claim indeterminacy wasn't "fundamental". If indeterminacy has a cause, not fundamental, then that causal mechanism can in principle carry the relevant correlation information with the particle from the time the correlation was created. If indeterminacy is fundamental, without cause, then this is not possible and a FTL mechanism is required for EPR correlations. But if indeterminacy is acausal, why can't correlations be acausal?

Once you allow quantum randomness to have a causal mechanism of any sort, then this same mechanism, in principle, allows correlation information to be carried by the particle from the initial interaction. It's ONLY the lack of a causal mechanism of indeterminacy that makes EPR weird. I don't get why that's so difficult.

No, Einstein most certainly would not have accepted Bell proof as a FTL mechanism, he would have considered it proof of his original claim that indeterminacy has a "causal" mechanism, which carries the correlation information from the initial interaction.
 
  • #373
Here is a link to the original EPR paper:
http://www.phys.uu.nl/~stiefelh/epr_latex.pdf

Take special note of the definition of reality. It specifically stated that a comprehensive definition was unnecessary, and what is provided is merely sufficient for the needed purposes, repeatedly. Sounds like my writing, and notes that many other ways exist to recognize reality. The point here is that narrowing in on the one definition provided isn't a valid rebuttal (hence the Neumann rejection), because it was merely chosen as "sufficient" as one way of recognizing reality relevant to the EPR paper argument.

Now the key sentence:
http://www.phys.uu.nl/~stiefelh/epr_latex.pdf said:
[...] we arrive at the conclusion that two physical quantities, with non-commuting operators, can have simultaneous reality.
Why did they come to this conclusion?
Because EPR correlations are REAL.
Because Bell's inequalities are VIOLATED.
I don't think, in their wildest imagination, they considered that future generations would actually call an empirically verified prediction a failure.

Now look at the definition given for a complete theory:
http://www.phys.uu.nl/~stiefelh/epr_latex.pdf said:
Every element of physical reality must have a counterpart of physical theory.
Thus the very act of postulating a FTL "mechanism" justifies the conclusion of the original EPR paper , due to the above correct prediction:
http://www.phys.uu.nl/~stiefelh/epr_latex.pdf said:
We are thus forced to conclude that the quantum-mechanical description of physical reality given by the wavefunction is not complete.
Thus either FTL mechanisms or local hidden variables fully justifies the claims of the paper, only a rejection of the paper itself is required to justify FTL mechanisms.

Now to reiterate "completeness". RQM defines QM as an "information theory". For an information theory to be "complete" does not require that every physical element that defines that information be defined. The definition provided by the EPR paper specifically extended "completeness" to not only include complete information, but also a physical specification of what defines that information. Thus both sides are arguing "completeness" while rejecting that their are two sets of definitions in use.

In no way, shape, or form did Einstein ever reject the validity of any prediction of QM whatsoever. He was an integral part of its development till it was declared complete.
 
  • #374
my_wan said:
Not sure how you can support that when in fact Einstein's argument required EPR correlations to be real (Bell's inequalities to be violated) as his justification (now empirical) to claim indeterminacy wasn't "fundamental". If indeterminacy has a cause, not fundamental, then that causal mechanism can in principle carry the relevant correlation information with the particle from the time the correlation was created. If indeterminacy is fundamental, without cause, then this is not possible and a FTL mechanism is required for EPR correlations. But if indeterminacy is acausal, why can't correlations be acausal?

Once you allow quantum randomness to have a causal mechanism of any sort, then this same mechanism, in principle, allows correlation information to be carried by the particle from the initial interaction. It's ONLY the lack of a causal mechanism of indeterminacy that makes EPR weird. I don't get why that's so difficult.

No, Einstein most certainly would not have accepted Bell proof as a FTL mechanism, he would have considered it proof of his original claim that indeterminacy has a "causal" mechanism, which carries the correlation information from the initial interaction.

Well, there are some differences in our views of the historical record. But that is really not surprising, it sort of depends on how you read them and in which order.

When you say "EPR correlations", I assume you mean the so called perfect correlations. Yes, EPR assumes those. There is an element of reality for all angle settings where Alice and Bob pick the same settings. So we agree about that. Einstein accepted this and assumed - reasonably for the time - that a locally causal theory could eventually replace/augment QM at some point in the future.

But Einstein obviously could never have known about Bell inequalities... they weren't discovered until almost 10 years after his death. That changed things dramatically, as Einstein's hopes were no longer feasible. I easily believe that Einstein would have accepted the Bell result as irrefutable. But would he have abandoned locality over realism (or vice versa)? I can't say.
 
  • #375
my_wan said:
... No, Einstein most certainly would not have accepted Bell proof as a FTL mechanism, he would have considered it proof of his original claim that indeterminacy has a "causal" mechanism, which carries the correlation information from the initial interaction.

I agree. The whole EPR question was if QM could be considered incomplete, in need of LHV or FTL. And if we today have proven that Einstein was right (QM needs LHV or FTL), then Einstein would of course be an advocate of finding a local mechanism to explain the paradox. I don’t think he would have started the research claiming – Well, I was right about EPR and the incompleteness of QM, and that also sadly proved GR/SR being totally wrong, in the proved FTL mechanism... Let’s start from scratch! :biggrin:
 
  • #376
my_wan said:
No, because if indeterminacy is not fundamental, then the information producing the correlation can simply be carried by the particles from the original interaction, like the marble analogy. Only the mechanism that carries it must be indeterminate, but not fundamentally so, i.e., a relational ensemble of real (though observer characterized) states. ...

I understand this, almost... the 'thing' that looks to us as a FTL mechanism, cannot be 'exposed' in its underlying determinism...?

Why I asked was because in the video in https://www.physicsforums.com/showpost.php?p=2721494&postcount=365" Anton Zeilinger talks about Quantum teleportation, and the reason why we can’t "beam" Alice over to Bob, is because HUP makes it impossible to measure Alice exactly, without destroying her (and then the joke about the "Heisenberg compensator" that "works very well, thank you").

But I have another (hopefully) tricky question for you:

Suppose we send 100 entangled photons towards the polarizer’s, and there is no FTL mechanism, all is handled by an 'underlying relational local ensemble' at the source.

What happen and how is this handled if we for example have one year between every entangled pair? Is there a "Global RAM" that 'memorizes' the statistics to be consistent with predictions of QM??
 
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  • #377
my_wan said:
1. Here is a link to the original EPR paper:
http://www.phys.uu.nl/~stiefelh/epr_latex.pdf

2. ... I don't think, in their wildest imagination, they considered that future generations would actually call an empirically verified prediction a failure.

3. In no way, shape, or form did Einstein ever reject the validity of any prediction of QM whatsoever. He was an integral part of its development till it was declared complete.

1. Waa, my own site is still down, which also contains this paper. SO thanks for posting a link.


2. Oh, but they were quite wrong on this key point. Per their conclusion:

"One could object to this conclusion on the
grounds that our criterion of reality is not suf-
ficiently restrictive. Indeed, one would not ar-
rive at our conclusion if one insisted that two
or more physical quantities can be regarded
as simultaneous elements of reality only when
they can be simultaneously measured or pre-
dicted. On this point of view, since either one
or the other, but not both simultaneously, of
the quantities P and Q can be predicted, they
are not simultaneously real. This makes the
reality of P and Q depend upon the process
of measurement carried out on the first system
in any way. No reasonable definition of reality
could be expected to permit this.

While we have thus shown that the wave
function does not provide a complete descrip-
tion of the physical reality, we left open the
question of whether or not such a description
exists. We believe, however, that such a theory
is possible."

Note how they say: no reasonable definition of reality will allow this! They absolutely did not see that P & Q are NOT simultaneously real (unless of course, there are FTL effects). Further, they believed that a more complete description of the system is possible! We now know that is not true. At least, not as EPR envisioned.


3. I would agree that Einstein did not reject the predictions of QM.
 
  • #378
?:bugeye:? This is confusing... even if it never is mentioned in words in the paper, when EPR talks about "P and Q" they are talking about Spin(p,q), right?? Or to be precise, simultaneously Vertical + Horizontal Spin in the same particle, right??

If this is correct, then what they are saying is:

1) The quantum-mechanical description of reality given by the wave function is not complete *OR*

2) When the operators corresponding to two physical quantities do not commute the two quantities cannot have simultaneous reality. Starting then with the assumption that the wave function does give a complete description of the physical reality, we arrived at the conclusion that two physical quantities, with non-cummuting operators, can have simultaneous reality.

Meaning: If we measure V spin at Alice we also make V spin at Bob real (entanglement). But then we can also measure H spin at Bob, but quantities that do not commute cannot be simultaneous real according to QM = QM description of reality given by the wave function is not complete!

Or did I miss something (again)??

Anyone interested in commuting, sorry communicating, are welcome.
 
  • #379
DevilsAvocado said:
?:bugeye:? This is confusing... even if it never is mentioned in words in the paper, when EPR talks about "P and Q" they are talking about Spin(p,q), right?? Or to be precise, simultaneously Vertical + Horizontal Spin in the same particle, right??

If this is correct, then what they are saying is:

1) The quantum-mechanical description of reality given by the wave function is not complete *OR*

2) When the operators corresponding to two physical quantities do not commute the two quantities cannot have simultaneous reality. Starting then with the assumption that the wave function does give a complete description of the physical reality, we arrived at the conclusion that two physical quantities, with non-cummuting operators, can have simultaneous reality.
QUOTE]

Could be P and Q (momentum and position), or could be non-commuting spins. I think it is a lot easier to talk about spin because then there is no confusion of the purity of their states (i.e. they are on a completely equal basis with each other, and each can take on a random value of either + or -).

An electron has 3 spins: x, y and z.

Now, keep in mind that they acknowledged that if QM is complete, there cannot be simultaneous independent reality of P & Q. On that I agree with EPR. The part I disagree with (as do most) is that it is an unreasonable to deny the simultaneous reality of P & Q. It is that last leap which led to their error.
 
  • #380
Nice, you called me out on the right issues, but made bad assumptions about my position.

DrChinese said:
Well, there are some differences in our views of the historical record. But that is really not surprising, it sort of depends on how you read them and in which order.
Yes, it was a nutshell history, and I did short change the significant contributions Bell's inequalities made with respect to realism. In my latest post I made it sound 'as if' the EPR correlations of the original paper are equivalent to Bell's inequalities, and this is very far from true. The fact is Bell's inequalities make fine distinctions in the character of some classes of causal mechanisms undreamed of in the original EPR paper, which merely chose a simple definition as "sufficient" for the simple case of existential correlations. The case for Einstein being wrong is actually predicated on a stronger argument made by Bell's theorem, which in fact rules out the simple operational definition of of reality used in the paper. The EPR did repeatedly note this, and referred to this definition this way: "Regarded not as necessary, but merely as sufficient, condition of reality, this criterion is in agreement with classical as well as quantum-mechanical ideas of reality." The underlined left a door open here that Bell's theorem has yet to close. The door that I started this debate with.

DrChinese said:
When you say "EPR correlations", I assume you mean the so called perfect correlations. Yes, EPR assumes those. There is an element of reality for all angle settings where Alice and Bob pick the same settings. So we agree about that. Einstein accepted this and assumed - reasonably for the time - that a locally causal theory could eventually replace/augment QM at some point in the future.

Yes, I spoke in terms of perfect correlations only in the last few posts. I can't specifically object on the term "element of reality", as it doesn't define itself. So up next I'll reiterate exactly what Bell's theorem assumes and the issue with that.

DrChinese said:
But Einstein obviously could never have known about Bell inequalities... they weren't discovered until almost 10 years after his death. That changed things dramatically, as Einstein's hopes were no longer feasible. I easily believe that Einstein would have accepted the Bell result as irrefutable. But would he have abandoned locality over realism (or vice versa)? I can't say.
True, Einstein couldn't know, but clearly the equivocation on the definition of reality in EPR, and later the rejection of Neumann's proof, showed an understanding of the issues in drawing a linear relation between ontic (perhaps unobservable) elements of nature and the variables they define. Neumann considered an ensemble K such that the subsets ki, kj, ..., should hold the properties of K, which they clearly don't. This is essentially the "preexisting property assumption" required by Bell's notion of reality. The same simplistic notion used in EPR, with equivocation. Bell was quiet clear that the inequality derivation itself didn't require any notion of realism at all. Question is, is this a "sufficient" case for realism in the general case, as it was in the more restricted argument in EPR? The answer is absolutely no. Bell merely ruled this simplistic class of intrinsic properties. Emergence is an ubiquitous phenomena in nature, making such linear assumptions unreasonable.

This paper goes over in some detail the limits of what Bell's theorem can say wrt realism.
http://arxiv.org/abs/0811.2862"
There simply is no a priori reason to assume ontic entities have preexisting properties independent of measurement in the classical or empirical sense. The fact is that models that take advantage of contextual/relational variables can successfully models correlation statistics. Within thermodynamics variances between intrinsic and extrinsic variables is a normal feature, which means non-commuting variables are to be expected. Conjugate variables have a very tight analog to these QM properties, which are only untenable when you assume measurables are preexisting properties. Preexisting properties also lead to the so called vacuum catastrophic, deepens the mystery of why the total energy of the Universe is apparently zero, virtual particles, etc.

None of this proves a realistic model is valid, local or otherwise. But to say the Bell's inequalities rules out locally realistic theories is simply not tenable. Yes Bell's results are irrefutable, it simply overreaching to say that ruling out naive linear relations between properties and things says much about realism at all. I see no reason to give up either locality or realism without a much better reason than an grossly overstated interpretation of Bell's theorem.
 
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  • #381
DrChinese said:
1. Waa, my own site is still down, which also contains this paper. SO thanks for posting a link.


2. Oh, but they were quite wrong on this key point. Per their conclusion:

"One could object to this conclusion on the
grounds that our criterion of reality is not suf-
ficiently restrictive. Indeed, one would not ar-
rive at our conclusion if one insisted that two
or more physical quantities can be regarded
as simultaneous elements of reality only when
they can be simultaneously measured or pre-
dicted. On this point of view, since either one
or the other, but not both simultaneously, of
the quantities P and Q can be predicted, they
are not simultaneously real. This makes the
reality of P and Q depend upon the process
of measurement carried out on the first system
in any way. No reasonable definition of reality
could be expected to permit this.

While we have thus shown that the wave
function does not provide a complete descrip-
tion of the physical reality, we left open the
question of whether or not such a description
exists. We believe, however, that such a theory
is possible."

Note how they say: no reasonable definition of reality will allow this! They absolutely did not see that P & Q are NOT simultaneously real (unless of course, there are FTL effects). Further, they believed that a more complete description of the system is possible! We now know that is not true. At least, not as EPR envisioned.


3. I would agree that Einstein did not reject the predictions of QM.
Yes, but this analysis is predicated on the 'not real' as defined by indeterminacy. What the paper was out to reject. Thus, to demonstrate what was defined there as "no reasonable definition of reality" requires the variables, I suppose are relational, to not be contained in a local ensemble, such that communication between the correlated pair is required for nonlocal realism. Yet to demonstrate that is the case via Bell's theorem requires the assumption that the measured properties of a single ensemble (particle) are innate properties of the subsets of that ensemble. It is the rejection of this assumption that allows local realistic models in accordance with Bell's inequalities.

Bell was genius is providing us with these constraints, and I prefer to use them as a map, rather than overgeneralize the impossibilities they provide. Thus we are at the same impasse, with properties of ensembles not innate to the subsets of that ensemble verses properties of particle pairs not innate to either particle alone, regardless of separation, as the defining difference of perspective.

So we have choice A and B:
A: Entangled particle pairs with individual properties not innate to either particle alone.
B: Particles are ensembles with properties not innate to the subsets of that ensemble.
Personally I think B is the most reasonable choice.
 
  • #382
my_wan said:
True, Einstein couldn't know, but clearly the equivocation on the definition of reality in EPR, and later the rejection of Neumann's proof, showed an understanding of the issues in drawing a linear relation between ontic (perhaps unobservable) elements of nature and the variables they define. Neumann considered an ensemble K such that the subsets ki, kj, ..., should hold the properties of K, which they clearly don't. This is essentially the "preexisting property assumption" required by Bell's notion of reality. The same simplistic notion used in EPR, with equivocation. Bell was quiet clear that the inequality derivation itself didn't require any notion of realism at all. Question is, is this a "sufficient" case for realism in the general case, as it was in the more restricted argument in EPR? The answer is absolutely no. Bell merely ruled this simplistic class of intrinsic properties. Emergence is an ubiquitous phenomena in nature, making such linear assumptions unreasonable.
I would like to agree with this point and provide something along the line from more practical side.
There is so called "entanglement distillation" and it's description in wikipedia says:
"Entanglement distillation can in this way overcome the degenerative influence of noisy quantum channels by transforming previously shared less entangled pairs into a smaller number of maximally entangled pairs (Bell states)."
To me this seems very much like emergence.
 
  • #383
zonde said:
I would like to agree with this point and provide something along the line from more practical side.
There is so called "entanglement distillation" and it's description in wikipedia says:
"Entanglement distillation can in this way overcome the degenerative influence of noisy quantum channels by transforming previously shared less entangled pairs into a smaller number of maximally entangled pairs (Bell states)."
To me this seems very much like emergence.

Only in the sense that the word used is the same.
 
  • #384
my_wan said:
This paper goes over in some detail the limits of what Bell's theorem can say wrt realism.
http://arxiv.org/abs/0811.2862"
There simply is no a priori reason to assume ontic entities have preexisting properties independent of measurement in the classical or empirical sense. The fact is that models that take advantage of contextual/relational variables can successfully models correlation statistics. Within thermodynamics variances between intrinsic and extrinsic variables is a normal feature, which means non-commuting variables are to be expected. Conjugate variables have a very tight analog to these QM properties, which are only untenable when you assume measurables are preexisting properties. Preexisting properties also lead to the so called vacuum catastrophic, deepens the mystery of why the total energy of the Universe is apparently zero, virtual particles, etc.

None of this proves a realistic model is valid, local or otherwise. But to say the Bell's inequalities rules out locally realistic theories is simply not tenable. Yes Bell's results are irrefutable, it simply overreaching to say that ruling out naive linear relations between properties and things says much about realism at all. I see no reason to give up either locality or realism without a much better reason than an grossly overstated interpretation of Bell's theorem.

I am not impressed by Laudisa, I am loosely familiar with his work as I scan almost every local realistic paper going into the arxiv. And I must say I am rather surprised by your position, it does not seem to follow from your prior statements. But I admit I still may not follow your position as there are some apparent contradictions (which I am sure are not actual contradictions). :smile:

1. Using Bell as a map (which I think is proper): do you think local realistic theories can yield predicitions consistent with QM?

2. How is the Bell generally acceptede conclusion "grossly overstated"? I mean, after decades of effort there is not ONE single local realistic candidate theory to consider. Every one can, thanks to Bell, be batted out of consideration. You must have seen how the work of Hess, Santos, and numerous others has been systematically dismantled. Not bad for being overstated: QM, 100; LR,0.

3. You say "contextual/relational variables can successfully models correlation statistics". To me, a contextual/relational model is not observer independent. Therefore, it is not realistic. So these sound like the words of someone who in fact denies realism. So are you in that camp or not?
 
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  • #385
DrChinese said:
I am not impressed by Laudisa, I am loosely familiar with his work as I scan almost every local realistic paper going into the arxiv. And I must say I am rather surprised by your position, it does not seem to follow from your prior statements. But I admit I still may not follow your position as there are some apparent contradictions (which I am sure are not actual contradictions). :smile:
Laudisa does ramble a lot. :smile:
I also think he overstates the certainty of validity of local models, which object to on the same grounds I object to certainty in ruling local models in general out. It seems your question #3 below contains the issue creating the apparent contradiction. I'll go though the questions.

DrChinese said:
1. Using Bell as a map (which I think is proper): do you think local realistic theories can yield predicitions consistent with QM?
In principle yes, whether cogency can actually pan out for the standard model I can't say. I was recently challenged by one of my favorite skeptics to write a computer program that mimicked EPR correlation statistics. I found this that claims to have done it (haven't looked that close yet):
http://msc.phys.rug.nl/pdf/athens06-deraedt1.pdf
I was considering a variation of an encryption scheme I once wrote, based on some (now defunct) notions of cross frame information embedding. Actually with FTL models I might reconsider a limited version of that. It embedded an encrypted message in a fake encrypted message. Anyway I'm considering these quasirandom sequences and what rules might be needed to mimic detector setting choices. Interesting problem anyway.

DrChinese said:
2. How is the Bell generally acceptede conclusion "grossly overstated"? I mean, after decades of effort there is not ONE single local realistic candidate theory to consider. Every one can, thanks to Bell, be batted out of consideration. You must have seen how the work of Hess, Santos, and numerous others has been systematically dismantled. Not bad for being overstated: QM, 100; LR,0.
I would refer to anything that is stated as 'proof' when it fails to rule out an entire class of possible exceptions grossly overstated. I'll get to that class in your next question. Making a 'proof' claim requires more than just invalidating the special cases on the table. Admittedly it also rules out entire classes of lhv's. It also lend cogency to FTL considerations, but local toy models can and do mimic EPR statistics, including stochastic hidden variables. I can't object to the claim of relatively unlikely, but almost certainly is an overstatement of what has been demonstrated by Bell's Theorem.

DrChinese said:
3. You say "contextual/relational variables can successfully models correlation statistics". To me, a contextual/relational model is not observer independent. Therefore, it is not realistic. So these sound like the words of someone who in fact denies realism. So are you in that camp or not?
I have a bit of confusion how you are defining contextual variables myself. Earlier I seen it referred to as measuring separate realities in this thread. That was a bit ambiguous considering MWI. Here you say the relational model is not observer independent, but fail to specify what it's independent of. There is a difference between a configuration space, and a variable which is dependent on the perspective in which that configuration space is measured. Thus the whole point of contextual variables is that they are not observer independent, but the reality of the configuration space is. Analogs to these types of variables everywhere, the most relevant of which are in GR. What follows is not a claim, but a demonstration of the issues involve in complaining that contextual variables are not observer independent.

Consider what a water wave means to a single water molecule. It's nothing more than a small momentary deflection, not even significant relative to the general random motion. Same thing for air molecules when I say "boo". What part of "boo" is contained in each air molecule? Is the sound "boo" a preexisting property of air molecules? Conjugate variables are common enough in classical physics. What properties are preexisting in this world is a good question, perhaps even the constants?

In GR we make a well justified operational distinction between mass and rest mass. In the general case mass is a contextual variable, but the mass is real. So how relevant is that distinction? Consider a particle in QFT: A particular excitation of a field. Ask what happens if the entire field was uniformly excited by this magnitude. We could assume the total vacuum energy density increases accordingly, but this reasoning lead us to the vacuum catastrophe, and I'd say a prediction 107 orders of magnitude off is trouble for that assumption. Then we have a zero total energy of the universe, GM_t^2/R = M_tc^2. This is pretty strong indication to me that the the entire universe, and everything we empirically measure about it, are purely contextual variables. Could it be that local field variances fully defines all empirical properties contextually, such that uniform absolute magnitudes of anything is meaningless, like gauge fields? This does not mean the configuration space that defined the variables isn't real, and almost certainly covariant. But trying to define reality solely in terms of the variables we measure wouldn't make much sense, in spite of the reality of covariant field variances.

As noted, I'm not trying to convince you that this is the way it is. Significant theoretical issues make this outline problematic. I'm merely trying to point out the issues in assuming that because contextual variables are not observer independent realism is out. Here I described a scenario where *all* variables are contextual, and still maintained realism. Everything you measure gets its metric from you, or some instrument, self referencing. You are a product of the very thing you are measuring, and not even space and time itself, the metric on which measurements are predicated, is non-contextual.
 
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  • #386
my_wan said:
In principle yes, whether cogency can actually pan out for the standard model I can't say. I was recently challenged by one of my favorite skeptics to write a computer program that mimicked EPR correlation statistics. I found this that claims to have done it (haven't looked that close yet):
http://msc.phys.rug.nl/pdf/athens06-deraedt1.pdf
I was considering a variation of an encryption scheme I once wrote, based on some (now defunct) notions of cross frame information embedding. Actually with FTL models I might reconsider a limited version of that. It embedded an encrypted message in a fake encrypted message. Anyway I'm considering these quasirandom sequences and what rules might be needed to mimic detector setting choices. Interesting problem anyway.

Not meaning to ignore the rest of your post, which I want to review in more detail.

However, I am a computer programmer by profession. I have performed extensive analysis of the De Raedt computer simulation you referenced. I obtained the line by line source code for their model, and have created a series of models that accurately mimic their code using Excel (since their stuff requires a lot of add-on software to run). Using Visual Basic, I create trial runs for a large number of iterations at various angles and graph them. This spreadsheet is available from my website and I will post the link (it was previously posted on another thread).

This shows that it is in fact possible to construct a "local realistic" algorithm that does not violate a Bell Inequality, but yields a subsample which does. Thus it does not reproduce the QM predictions for the full universe, but does for a so-call "unfair sample". It is a very interesting piece of work.

However, my spreadsheet goes on to show why the same model is fatally flawed. In fact, it shows why pretty much ANY similar model is also fatally flawed. As far as I know, this analysis is original although I am sure there are others who have figured this out as well. I don't think anyone else has actually programmed the problem area so as to demonstrate it using the same technique as the De Raedt model itself.

My point being that it is far easier to claim success for a model than to actually produce that success. I will gladly take on any local realistic model which, like the De Raedt model, offers a specific algorithm which is actually "local" and "realistic" (since we are talking computer simulation). I can assure you, there isn't likely to be a model which can withstand attack. All this because Bell is in fact a map.

And keep in mind that the De Raedt model does not purport to mimic the results of all QM in the first place - so technically it is not a local realistic candidate theory. It is really an attempt to demonstrate that Bell can be beat, but it does not actually accomplish that in the end.
 
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  • #387
DrChinese said:
I am not going to waste my time trying to figure out this gibberish. If you want to use his formula to present a valid set of data, I will look at it. BUT QUIT SAYING IT WITHOUT SHOWING IT!
So, what are you saying? That Unnikrishnan's formulation doesn't reproduce the qm predictions. That's just silly. Read the paper.

If you're saying that his formulation shouldn't be interpreted as local realistic in the sense of EPR-Bell, then I agree with you.

But it is an explicitly local model which expresses the conceptual points I've been making.

DrChinese said:
The entire point of Bell is that he cannot follow through on his claims.
His claim is that we don't need nonlocality to understand the correlations in terms of a local common cause. He's made an explicitly local model using a relational variable produced via emission process. And he correctly reproduces the qm predictions.

I agree with you that Bell put a stopper on explicitly local realistic models which, in effect, require the joint results to be caused by the variables which cause individual results. It's impossible to do that because the joint results are determined by a RELATIONSHIP between the counter-propagating disturbances which is NOT the same thing as the variables which determine the individual results.
 
  • #388
IcedEcliptic said:
I've read that paper, and I believe that Dr. Chinese summed up that tidibt quite well.
Unnikrishnan made an explicitly local model of entanglement that reproduces the qm results. I think that if you had read and understood the paper, then you would see how it relates to the conceptual points I've been trying to get across.

IcedEcliptic said:
The issue is not that the formalism if QM is not untenable in some ways, but rather that you are arguing for a loophole that I, along with many others believe has been utterly disprove as a factor.
I'm not arguing loophole(s). That's Zonde.

IcedEcliptic said:
You both argue against something, and grasp at straws to do so, but really your pages of arguments boil down to not liking SQM, and not having a superior theory in its place.
I'm not arguing for LHV models or against Bell. I'm arguing that we can understand entanglement correlations without resorting to nonlocality, or weird alternate realities. I don't think you've been paying close enough attention to what's been said to label anyone in this discussion a crackpot.

IcedEcliptic said:
The paper is like your arguments which Dr. Chinese continues to rip to confetti; it is scattered, distracting, and fundamentally lacking in substance. Its only strength is that you have yet to state enough of your position to refute it on purely scientific grounds, but that is yet another weakness. You go on and on about a non-existent loophole, and Zonde has ideas about Malus' Law that are between laughable and upsetting.
Zonde is the loophole person. I'm the one who brought up the applicability of Malus Law to certain situations.

IcedEcliptic said:
Your papers are crocks, you have pages of nonsense and rhetoric, but you continue your circular retreat, and in theory you will keep this up until a mentor finally accepts that you are a genuine crackpot and not just misguided.
Are you calling Unnikrishnan a crackpot now?
 
  • #389
Here is the link to the Excel spreadsheet models I created around the De Raedt simulations:

http://www.drchinese.com/David/DeRaedtComputerSimulation.EPRBwithPhotons.B.xls"

To see the code I wrote, go into the Visual Basic editor. Sheet A shows their model working correctly. Sheet B shows their model working incorrectly for a setup which matches their base assumptions.
 
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  • #390
DrChinese said:
Here are the links to the Excel spreadsheet models I created around the De Raedt simulations:

http://www.drchinese.com/David/DeRaedtComputerSimulation.EPRBwithPhotons.B.xls"

To see the code I wrote, go into the Visual Basic editor.

You are very devout in your hobby, I respect this! Thanks for showing us the fruits of your labour.
 
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