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

[DevilsAvocado]

There's worse, much worse...

Please! Don’t tell me! I don’t think I can take it anymore...
(What’s next? A Bayesian 'cranky theory' "proving" that the Earth is flat and in the center of the Solar system and the Universe! )

 

[JesseM]

A. F. Kracklauer - Non-loco Physics
"Loco'' (Spanish for 'crazy'). Contemporary Physics is vexed by some really "loco'' ideas, with nonlocality and asymmetric aging leading the list.
...
A second motivation is sociological. Some see a mutual interplay between fundamental science and the development of civilization. If this notion is accepted, then physics, as a social enterprise, has some responsibility to support those things making positive contributions to civilization by being the exemplar of rationality, contrary to the current fashion of spewing forth ever new and more exotic pop-psycho-sci-fi contrivances, i.e., loco ideas.

Just noticed this--apparently the guy wants to disprove relativistic time dilation as well! You can see him making some ridiculous arguments against time dilation experiments (which have established 'asymmetric aging' beyond any reasonable doubt) in publication 4, "analysis of and remedy for asymmetric aging (twin paradox)", on this page of his site.

 

[DrChinese]

Thus, there are generally two ways to account for EPR-Bell correlations. 1) The detection events are separable and you have superluminal exchange of information. 2) The detection events are not separable, e.g., the spin of the entangled electrons is not a property of each electron. The first property is often called "locality" and the second property "realism."

Great description, RUTA!

To those that try to dissect the words and formulae of Bell (and I count myself in that group sometimes): You can see from RUTA's description that locality and separability can have meanings and implications that can somewhat be interchanged by your choice of base definitions or perspectives.

For example: Norsen (mentioned earlier in the discussion here) sees Bell (2) as defining separability, and he equates that with locality. So separability is spatial/temporal. On the other hand, RUTA is classifying separability according to wave functions. Particles that share a wave function do not have independent (separable) observables - which leans towards the realistic side of the subject.

Further: Norsen sees lack of separability as automatically indicating we live in a non-local universe. Thus c is not a constraint on influences from elsewhere. On the other hand, RUTA (and I probably shouldn't supply words when RUTA can speak for himself) might tend to see lack of separability as indicative that the observer and observed systems are themselves not independent. This perspective was specifically mentioned in the 1935 EPR paper, although EPR rejected this option as not "reasonable" (because that would make the reality of one system dependent on the nature of observation made on another). Unreasonable or not, if it is considered as an option then there are no contradictions with Bell.

Lastly, there is the issue of mechanism. Once you reject local realism, can you account for the "how"? In the Bohmian view, there is action at a distance and c is not respected. Apparently, and I am not suitably versed in this department, the action potential of one particle upon another does not diminish with distance. In the view of RUTA (see more on Relational Blockworld at http://arxiv.org/abs/0908.4348 ): the mechanism can be accounted for without action at distance. However, there are elements whereby the future and the past interact; and this provides the basis for what might appear as action at a distance (even though c is fully respected). I don't think "interact" is the correct word as RBW is sort of Zen-like in its description; there are no events exactly. But I will ask RUTA to correct any misconceptions I have introduced; ditto on the Bohmian side: Maaneli, Demystifier?

So this is some very interesting stuff.

 

[DrChinese]

I look at the experimental setups involved and I see a local optical 'explanation' for the observed correlations. I've talked to maybe two dozen working experimental physicists about this and they agree.

So you are saying that there are a number (24 that you know) of people who all are familiar with the same local realistic mechanism for explaining entanglement "optically". And yet I have never even heard of this. Does it have a name so I can look it up? Or is just "the mechanism everybody else knows about" that hasn't yet been published? Or maybe... just maybe... you should consider supplying a reference when you make claims like this.

 

[billschnieder]

21 papers on arXiv.org. Where is the "bunch" of peer reviewed papers? These two are peer reviewed before 2000
...
And the only one peer reviewed after 2000, is this one:
...

Either you are just being dishonest, or you can not count, or maybe you do not know what a peer reviewed article means, or you do not know how to find peer reviewed articles. Here is a list from the page you linked to.

• On the nature of information-erasing , Journal of Modern Optics, Volume 54, Numbers 16-17, November 2007 , pp. 2365-2371(7)
• Nonlocality, Bell's Ansatz and Probability Optics and Spectroscopy. 103 (3) 451-450 (2007)
• "What's wrong with this rebuttal,"Found. Phys. Lett. 19 (6) 625-629 (2006).
• ``Quantum'' beats in classical physics,, J. of Russian Laser Research 26 (6) 524-529 (2005)
• Oh Photon, Photon, whither art thou gone?, in: Proceedings of SPIE, 5866 (2005).
• EPR-B correlations: non-locality or geometry?, J. Nonlinear Math. Phys. 11(Supp.) 104-109 (2004).
• EPR-B correlations: quantum mechanics or just geometry?, J. Opt. B (Semiclass. & Quant.) 6 S544-S548 (2004)
• Exclusion of correlation in the theorem of Bell, in: Foundations of Probability and Physics-2, 385-398
• One less quantum mystery, J. Opt. B (Semiclass. & Quant.) 4, S469-S472 (2002)
• Is entanglement always entangled?, J. Opt. B (Semiclass. & Quant.) 4, S121-S126 (2002)
• ``Complementarity'' or Schizophrenia: is Probability in Quantum Mechanics Information or Onta?, in: Foundations of Probability and Physics, 219-235 (2001)
• The Improbability of Non-locality, Phys. Essays, 15(2) 162-171 (2002)
• La `theorem' de Bell, est-elle al plus grand meprise de l'histoire de la physique?, Ann. Fond. L. de Broglie 25(2) 193-207 (2000)
• Pilot wave steerage: a mechanism and test, Found. Phys. Lett. 12(2) 441-453 (1999).
• Objective Local Models for Would-be Nonlocal Physics, in: Instantaneous aad: Pro & Contra, 363-372 (1999).
• An Intuitive Paradigm for Quantum Mechanics, Phys. Essays 5 (2) 226-234 (1992)
• A theory of the electromagnetic two-body interaction. J. Math. Phys. 19(4) 838-841 (1978)
• Comment on: Classical derivation of Planck Spectrum, Phys. Rev. D 14, 654-655 (1976)
• On the Imaginable Content of de Broglie Waves, Scientia, 109 ,111-120 (1974).
• Comment on: Derivation of Schroedinger's Equation from Newtonian Mechanics, Phys. Rev. D 10(4) 1358-1360 (1974).
• A geometric proof of no-interaction theorems, J.Math Phys. 17(5) 693-694 (1974)

Ad-hominem http://dictionary.reference.com/browse/ad+hominem

1. appealing to one's prejudices, emotions, or special interests rather than to one's intellect or reason.
2. attacking an opponent's character rather than answering his argument.

http://en.wikipedia.org/wiki/Ad_hominem

Ad hominem abusive
Ad hominem abusive usually involves insulting or belittling one's opponent, but can also involve pointing out factual but ostensible character flaws or actions which are irrelevant to the opponent's argument. This tactic is logically fallacious because insults and even true negative facts about the opponent's personal character have nothing to do with the logical merits of the opponent's arguments or assertions.
...
Guilt by association
Guilt by association can sometimes also be a type of ad hominem fallacy, if the argument attacks a source because of the similarity between the views of someone making an argument and other proponents of the argument.
This form of the argument is as follows:

Source A makes claim P.
Group B also make claim P.
Therefore, source A is a member of group B.

Fallacy -- http://en.wikipedia.org/wiki/Fallacy

In logic and rhetoric, a fallacy is a misconception resulting from incorrect reasoning in argumentation. By accident or design, fallacies may exploit emotional triggers in the listener or interlocutor (e.g. appeal to emotion), or take advantage of social relationships between people (e.g. argument from authority). Fallacious arguments are often structured using rhetorical patterns that obscure the logical argument

 

[my_wan]

Please! Don’t tell me! I don’t think I can take it anymore...
(What’s next? A Bayesian 'cranky theory' "proving" that the Earth is flat and in the center of the Solar system and the Universe! )

http://theflatEarth'society.org/
You can also see their experimental evidence here:
http://www.theflatEarth'society.org/tiki/tiki-index.php
Oh, and that's not even the worst that can be found

 

[DevilsAvocado]

Just noticed this--apparently the guy wants to disprove relativistic time dilation as well! You can see him making some ridiculous arguments against time dilation experiments (which have established 'asymmetric aging' beyond any reasonable doubt) in publication 4, "analysis of and remedy for asymmetric aging (twin paradox)", on this page of his site.

Well, what can I say?? The man is a "crackpot miracle"... It’s not only QM that’s "totally wrong"! Albert Einstein also goes down the Crackpot-Kracklauer-Drain??

(I sure hope Crackpot Kracklauer doesn’t use GPS in his car, because this would not work without QM atomic clocks + SR/GR correction for time dilation effects and gravitational frequency shift!)

This is remarkable... ThomasT & billschnieder thinks Crackpot Kracklauer is a "great scientist"...


JesseM, I really admire yours (and DrC’s) enormous patience and great skills, in trying to educate users like billschnieder. To me it looks like ThomasT has shown some willingness to an honest intellectual discussion and some openness to input and logical argumentation. But billschnieder on the other hand, is a wall of weird preconceptions, mainly based on the crazy ideas of Crackpot Kracklauer. That’s why your discussion ended the way it did. You did all you could – but it was a dead end from the beginning.

And there are other terrible examples of billschnieder’s 'technique' in other threads on PF (I tried to warn you).

I’m only a layman. I don’t have the great skills and deep knowledge you and many others here posses. But I do think I have one 'skill' – common sense and ability to judge what’s reasonable or not (which some "sophisticated gentlemen" in this thread apparently lacks).

Crackpot Kracklauer is not reasonable.


I must apologize to all "casual readers" for this "unpleasant episode" in this thread. I generally don’t find it interesting or productive to start "fights". But this was an exception, and someone had to push the "alarm button".

I hope we all can continue to discuss the matters of EPR and Bell's Theorem in an open, stimulating and productive way, as before.

I’m working on some "new" material from John Bell himself, never shown or discussed on PF. I think (hope) everyone will find it (very) interesting. I’m a little short of time at the moment, but I hope I can get it ready for 'publishing' ASAP.

Again – Sorry for the latest "mess".

/DA

 

[DevilsAvocado]

Great description, RUTA!

I agree! Captain RUTA is a great teacher! And most of all I admire him for implementing this little 'tips':

"Everything should be made as simple as possible, but not simpler" -- Albert Einstein

 

[DevilsAvocado]

Ad-hominem
Fallacy

Please billschnieder, you are making a fool of yourself.

 

[DevilsAvocado]

http://theflatEarth'society.org/
You can also see their experimental evidence here:
http://www.theflatEarth'society.org/tiki/tiki-index.php
Oh, and that's not even the worst that can be found

 

[ThomasT]

... And the only one peer reviewed after 2000, is this one: ...

Are you being intentionally dishonest about this? All anyone has to do is go to the guy's website and click on the links to see that what you're saying wrt the number of papers he's published (since 1999) in peer reviewed journals is false. There's at least 8 by my count, maybe more. A couple were published in the same journals that Stuckey (RUTA) has published in.

The question is why you risk all your credibility for a 100% crackpot as A. F. Kracklauer? ... A completely lost "independent researcher" with a crazy homepage at freehosting.com, and you are supporting this guy!? Why??

Where did I say that I support his ideas? I did say that some of his stuff looked like it might be interesting, and that he seemed to have a clear writing style.

I don't like what I see as your personal attack on someone whose views you happen to oppose. I'm not familiar with Kracklauer's stuff, but I intend to get around to reading it. Until then, I can't speak to whether or not I think any of his ideas or arguments are right or wrong. But even if I eventually conclude that ALL of his ideas and arguments are wrong, I certainly won't be calling him names because of it.

For a while in this thread you were following a line of reasoning, and I was enjoying your posts (even if I didn't agree with all your reasoning or tentative conclusions -- though some I did agree with -- not that that matters). But I don't see the utility in your current line of personal attacks. You can pursue your political agenda in another forum (or maybe not). Anyway, this is a science forum, and this is a thread about the grounds for assuming that nature is nonlocal. If you want to make an argument, or present an idea about that, then fine, but the personal stuff is annoying. Bottom line, I don't care if Kracklauer is crazy or not. If he's got any good ideas then I want to know about them. Eventually, though probably not real soon, I'll find out for myself.

I know you dislike nonlocality very much, and are fighting to find a "solution".

I couldn't care less if nonlocality or ftl exist or not. In fact, it would be very exciting if they did. But the evidence just doesn't support that conclusion.

The scientific method requires two basic questions be answered whenever some new property of reality or some paradigm changing, revolutionary view of reality is proposed. (1) What do you mean, and (2) how do you know? If you'd like to contribute to the effort to answer those questions, to discern the truth from the fiction wrt nonlocality and related considerations, then that would be a welcome change from your recent postings.

But don’t you think this is a 'little' too "far out"? This man has a mental problem:

A. F. Kracklauer - Non-loco Physics
"Loco'' (Spanish for 'crazy'). Contemporary Physics is vexed by some really "loco'' ideas, with nonlocality and asymmetric aging leading the list.
...
A second motivation is sociological. Some see a mutual interplay between fundamental science and the development of civilization. If this notion is accepted, then physics, as a social enterprise, has some responsibility to support those things making positive contributions to civilization by being the exemplar of rationality, contrary to the current fashion of spewing forth ever new and more exotic pop-psycho-sci-fi contrivances, i.e., loco ideas.

Well, he's saying that physical science should be an exemplar of rationality. Nothing crazy about that. Now, I will say that my superficial impression of his ideas on asymmetric or differential aging seems to be contrary to the way I've learned to think about it. That is, I believe that differential aging is pretty much a demonstrated fact of nature. But, I haven't read his paper(s) on this yet. So, I don't know exactly what he's saying about this, or his arguments. By themselves, the above quotes don't seem crazy. Even if they're grossly wrong, that doesn't imply that the guy is crazy. And if he has an agenda, even a personal one, that influences his approach and reasoning, well, I don't think that's at all unusual, and certainly not an indicator of 'mental illness'. Maybe in your imagination there are scientists whose work isn't influenced by 'nonscientific' factors.

"Complementarity" or Schizophrenia: is Probability in Quantum Mechanics Information or Onta?
ABSTRACT. Of the various “complimentarities” or “dualities” evident in Quantum Mechanics (QM), among the most vexing is that afflicting the character of a ‘wave function,’ which at once is to be something ontological because it diffracts at material boundaries, and something epistemological because it carries only probabilistic information. Herein a description of a paradigm, a conceptual model of physical effects, will be presented, that, perhaps, can provide an understanding of this schizophrenic nature of wave functions. It is based on Stochastic Electrodynamics (SED), a candidate theory to elucidate the mysteries of QM. The fundamental assumption underlying SED is the supposed existence of a certain sort of random, electromagnetic background, the nature of which, it is hoped, will ultimately account for the behavior of atomic scale entities as described usually by QM.
In addition, the interplay of this paradigm with Bell’s ‘no-go’ theorem for local, realistic extentions of QM will be analyzed.

I think the title was intended to get attention -- so that people would actually read the paper. Nothing crazy about that. Despite the fact that he might be, strictly speaking, using the term 'schizophrenia' incorrectly, I don't have an opinion wrt the merits of the content of the paper, not having read it yet. Have you read it?

The quantum mechanics of abortion
Does quantum mechanics have anything to do with abortion? Something, maybe. Quantum mechanics is the theory that encodes the mathematical patterns involved in the chemical bond. The chemical bond, in turn, writ big, or rather, writ oft, is the tool for assembling DNA, the crucial stuff of living matter. So, as the non plus ultra of life, the quantum mechanical chemical bond, may well have some relevance to abortion too, as an event affecting life.

When I first read this, I thought that maybe the guy really is crazy -- like maybe another abortion nut or whatever. But since the paper was only one page, I read it. He seems to be making a very reasonable social commentary.

He concludes with:

In any case, in the end quantum mechanics throws little light on these standards, except from its essentially probabilistic nature. This feature tells us that bond formation needs no ‘breath of life,’ or other mystical ingredient, it is a random event, it just happens, sometimes for no good reason. All the above seems to imply that science and logic can not be used to unequivocably evaluate abortion ethically. For what it’s worth, the morally superior stance, surely is the one which, no matter how and when life starts and ends, tends to cause people to turn to it less often. Practically this means avoiding unwanted pregnancies beforehand by promoting reproductive hygiene, and then providing material and financial support for single or disadvantaged mothers who failed with prevention afterwards. It is regrettable that an all too common sort of mental confusion, especially in the voting booth, leads ‘right-to-lifers’ themselves to become opponents of these practical means to actually reduce the occasions for abortion, thereby serving effectively as champions of the ‘evil’ they themselves disparage!

When did you last hear a "scientist" speculate around quantum mechanics and ABORTION?

As I said – this is the worst crackpot I have ever seen, and I think you should make it very clear that you are not backing up this man and his totally crazy ideas. This is not science.

Right. It's not science. Nor, I think, is it meant to be taken as such. It's an essay that presents some interesting and reasonable observations by a scientist with an active social conscience. Keep in mind that the US is full of Christian fanatics who would twist any scientific finding or paradigm to support their religious agendas. Kracklauer's program, it seems to me so far, is to oppose that sort of thing and also to oppose what some might see as an increasing tendency toward metaphysical constructions and 'mysticism' in 'mainstream' physics.

So, if that's all you've got, then 'case dismissed', as they say. From what I've seen so far, I think you owe Kracklauer and the contributors to, and observers of, this thread an apology. However, if you really just want to discredit the guy, then keep digging. That should at least keep you busy, and hopefully not posting your personal attacks, for a while. But keep in mind that your posts regarding Kracklauer are quite off topic. Maybe, eventually, some thoughtful moderator is going to inform you of that.

 

[ThomasT]

Well, can you present your local optical explanation in detail, either here or on a new
thread? You'll need to present it in enough quantitative detail that we can calculate
what measurement outcome will occur (or what the probability is for different outcomes)
given knowledge of a detector settings and the local hidden variables at the location of
the measurement (like the 'polarization vector' of the particle being measured, if that's
your hidden variable).

It isn't 'my' optical explanation. It's optics. There's two polarizers, a and b. They can both be on side A, or both be on side B, or one on each side. There's a randomly varying optical vector extending between the two polarizers. The resultant, measured, joint intensity of the light (the coincident photon flux) will vary as cos^2 (a-b). Of course the exact calculation will depend on the setup, but the point is that whenever crossed polarizers are jointly analyzing light from a random source, then this optical law applies.

I'm no expert, so if there's something essentially wrong with this, then let me know. If it's, in principle, ok, then I don't see any reason to suppose that anything nonlocal or ftl is happening.

Further, as DrC pointed out, a slight rotation of a wave plate is all that's necessary to produce polarization entanglement in certain OPDC Bell tests. Again, this doesn't suggest anything nonlocal or ftl to me. Does it to you?

So, this is the first problem I have with the assumption of nonlocality -- that there's nothing wrt Bell test setups and results, sans Bell's theorem (Bell inequalities) which warrants the assumption of nonlocality. If you put both polarizers on side A or side B, you get the same results as when you put one polarizer at A and one at B. But we don't think that anything nonlocal is going on when we have both polarizers on side A or side B. These are just simple polariscopic setups. But the joint results are the same as when we have one polarizer at A and one at B. So, why does this latter setup require a 'nonlocal' explanation? Well, the way I currently think about it, it doesn't.

The same sort of reasoning applies to OPDC setups where a slight rotation of a wave plate produces entanglement statistics wrt joint polarization measurements. Should I assume that this slight rotation has somehow precipitated nonlocal or ftl 'communications' in some realm underlying that of electromagnetic radiation? This just seems a bit silly to me. But if you can convince me otherwise, then I'm all ears, so to speak.

No, A and B are not independent in their marginal probabilities (which determine the
actual observed frequencies of different measurement outcomes), only in their
probabilities conditioned on λ. I've asked whether you understand the distinction a
bunch of times and you never answer.

I don't think the distinction matters. No matter how it's parsed, or how one chooses to express probability analogs for Bell's (2), the bottom line is that the joint probability is being modeled as the product of the separate probabilities. So, no matter what was intended, the form of Bell's (2) effectively models the two resultant data sets as independent. This was Bell's explicit expression of locality. The problem is that its intended function as an expression of locality is superceded by its effective function as an expression of statistical independence between the data sets.

 

[ThomasT]

So you are saying that there are a number (24 that you know) of people who all are familiar with the same local realistic mechanism for explaining entanglement "optically". And yet I have never even heard of this. Does it have a name so I can look it up? Or is just "the mechanism everybody else knows about" that hasn't yet been published? Or maybe... just maybe... you should consider supplying a reference when you make claims like this.

I was referring to casual conversations over the course of 8 or 9 years. So, no, you wouldn't have heard of 'it'. I would describe an optical Bell test setup, recount the results, and ask them if they thought the results indicated that any sort of 'nonlocal' or ftl 'communication' was necessary to understand them, and they would say no. I don't know exactly how many physicists I engaged in these conversations, but the impression I got was that none of them thought that anything mysterious (beyond the mystery of light itself) was going on in the experiments we discussed. The consensus was that it's just optics as usual -- ie., the correlations are due to the joint analysis of random polarizations by crossed polarizers.

Positing the existence of disturbances propagating at > c^9 (or 'instantaneously', whatever that might mean) is a nifty way to account for the correlations in optical Bell tests, but it just seems to me, and apparently lots of others (including Mermin, Jaynes, 't Hooft, etc.), to be too simplistic a solution to the conundra presented by the various interpretations of Bell's theorem. Anyway, those who do choose to advocate nonlocality as an 'explanation' are then left with the formidable task of explaining the explanation. So far, it's just metaphysics. But don't get me wrong, I like metaphysical speculations. It's just that I like them to be well grounded in accepted physics -- and, unfortunately, nonlocality isn't.

...if you accept Malus - combined with the assumption that there is a specific but unknown polarization for entangled photons - then probably you would conclude that Bell (2) is false.

Well, Malus Law is an empirically well established optical law. And since we know from experiments that, assuming that nature is evolving in accordance with the principle of local action, Bell's (2) is false, then what should we conclude? That there is some nonlocal or ftl 'mechanism' at work in entanglement situations, or that Bell's (2) simply misrepresents the experimental situation? What's being suggested is that the latter alternative is the more reasonable hypothesis, and that this hypothesis has yet to be definitively dismissed.

 

[JesseM]

It isn't 'my' optical explanation. It's optics. There's two polarizers, a and b. They can both be on side A, or both be on side B, or one on each side. There's a randomly varying optical vector extending between the two polarizers. The resultant, measured, joint intensity of the light (the coincident photon flux) will vary as cos^2 (a-b)

Your claim here is completely ill-defined. What is "joint intensity" supposed to mean in the context of optics? It appears to be completely meaningless in the context of classical optics, where there are no probabilities and thus no joint probabilities. Now, it's true that if the polarization of a light beam is v and the angle of the polarizer is a, then in classical optics the reduction in intensity as the light goes through the polarizer will be cos^2(a-v), that's just Malus' law. In quantum physics intensity is proportional to photon number, so are you suggesting that for a beam with polarization v passing through a polarizer at angle a, each photon has a probability of cos^2(a-v) of passing through the polarizer? And then the "joint intensity" would be based on imagining photons are sent to the different detectors in pairs, so the probability both photons make it through the detectors would be cos^2(a-v)*cos^2(b-v)? If so, this would not give a probability of cos^2(a-b) that both photons make it through (I showed this in my third-to-last paragraph of this post, a section you never responded to even when I reposted that paragraph in a later post).

I don't think the distinction matters. No matter how it's parsed, or how one chooses to express probability analogs for Bell's (2), the bottom line is that the joint probability is being modeled as the product of the separate probabilities.

Huh? The joint probability P(AB) is not being modeled as the product of P(A)*P(B) by Bell's equation. Do you disagree?

 

[DrChinese]

I was referring to casual conversations over the course of 8 or 9 years. So, no, you wouldn't have heard of 'it'. I would describe an optical Bell test setup, recount the results, and ask them if they thought the results indicated that any sort of 'nonlocal' or ftl 'communication' was necessary to understand them, and they would say no. I don't know exactly how many physicists I engaged in these conversations, but the impression I got was that none of them thought that anything mysterious (beyond the mystery of light itself) was going on in the experiments we discussed. The consensus was that it's just optics as usual -- ie., the correlations are due to the joint analysis of random polarizations by crossed polarizers.

Once again, you completely ignored the fact that this is false and you have NO reference for an outlandish statement. I would like to see this from any textbook. Quit stating your opinion by placing it in the mouth of unnamed others.

Reference, citation = ??

 

[DrChinese]

Huh? The joint probability P(AB) is not being modeled as the product of P(A)*P(B) by Bell's equation. Do you disagree?

ThomasT doesn't follow this correctly and keeps returning to something that is completely wrong. So this is intended for ThomasT:

1) If optics were the ruling issue, we would see Product State statistics. And those are different than what are observed. Product State stats are .5(.5+cos^2(theta)).

2) Entangled state statistics APPEAR to match Malus but that is something of a coincidence. Yes, it is cos^2(theta). And that is the Malus formula. But that is where it ends. If Malus applied, you would actually get the formula in 1) above.

Entanglement is a PURELY quantum effect and there is NO optical analog. I don't know how many different ways I can say this to make ThomasT understand it.

 

[my_wan]

DrC,
Perhaps you can be more clear. When you say:
1) If optics were the ruling issue, we would see Product State statistics.

Is this not essentially equivalent to saying, based on optics alone, that given theta = x then 2theta = 2x?, or some linear multiple for all theta. Malus law doesn't work this way even in standard optics.

I don't see using Malus law to show the same behavior pattern as relevant in resolving the issue, but neither does calling a one to one quantitative correspondence only an apparent match make much sense to me. As noted, by itself it doesn't resolve the realism issue, and standard optics allows a greater range of presumptions about how this result might be classical. The simplest of such presumptions being unequivocally ruled out by EPR correlation experiments. Yet perhaps you could be more specific in claiming an exact numerical match is an illusion.

Perhaps the rebuttal should involve the extra constraints BI imposes on possible mechanisms, rather than simply claiming the a quantitative correspondence is an illusion. Because I really don't think you can demonstrate that Malus law, standard optics, allows arbitrary choices of theta that leads to linear polarizer path statistics.

To illustrate, consider a standard polarized beam of light. Take the polarization of the light beam to be something other than theta = 0, and offset the polarizer/detector from the light beam on that same coordinate system. It breaks Malus law when you demand arbitrary coordinate choices, even in standard optics. This same demand that is insisted on to model EPR correlations that is also broken in standard optics.

Yes, I think these issues are fundamentally related. No, I don't think simply pointing out the relationship within standard optics, by itself, represents a resolution to the issue. The fact that it could be interpreted differently within the context of standard optics ignores the extra properties/things relationship constraints that EPR correlation experiments are sensitive to.

 

[JesseM]

I don't see using Malus law to show the same behavior pattern as relevant in resolving the issue, but neither does calling a one to one quantitative correspondence only an apparent match make much sense to me.

"One to one quantitative correspondence" between what and what? the cos^2 in Malus' law is for the difference between the angle of a polarizer and the polarization angle of a beam hitting it at the same location, the cos^2 in entanglement experiments is for the difference in angles between two polarizers at completely different locations making measurements on different particles. There's no way to use the first cos^2 law to derive the second one, whatever ThomasT may think.

As noted, by itself it doesn't resolve the realism issue, and standard optics allows a greater range of presumptions about how this result might be classical.

Why a "greater range of presumptions"? Standard optics can be derived from Maxwell's laws, which is a perfect example of a local realist theory of physics, so Bell's theorem definitely applies to anything in optics (and it's impossible to use classical optics to get a violation of Bell inequalities).

To illustrate, consider a standard polarized beam of light. Take the polarization of the light beam to be something other than theta = 0, and offset the polarizer/detector from the light beam on that same coordinate system. It breaks Malus law when you demand arbitrary coordinate choices, even in standard optics. This same demand that is insisted on to model EPR correlations that is also broken in standard optics.

Malus' law is only based on the difference in angle between the beam and the polarizer, so it doesn't get violated depending on how your coordinate system defines the angle of the beam. Are you suggesting otherwise?

 

[ThomasT]

Once again, you completely ignored the fact that this is false and you have NO reference for an outlandish statement.

Ok, so you don't think that a randomly varying polarization vector being jointly analyzed by crossed polarizers is a good way to think about it? Then how about when you put both polarizers on the same side? How would you think about that situation?

1) If optics were the ruling issue, we would see Product State statistics. And those are different than what are observed. Product State stats are .5(.5+cos^2(theta)).
2) Entangled state statistics APPEAR to match Malus but that is something of a coincidence. Yes, it is cos^2(theta). And that is the Malus formula. But that is where it ends. If Malus applied, you would actually get the formula in 1) above.
3) Entanglement is a PURELY quantum effect and there is NO optical analog.

1) Well, these are optics experiments, so why wouldn't optics be the ruling issue?
2) Do you think that Malus Law doesn't apply in quantum optics?
3) Statements like this don't do it for me. The goal is to understand the correlations, not keep them mysterious. If you want to think that something nonlocal or ftl kicks in simply because single photons are being detected, or because a polarizer has been moved, or a wave plate adjusted, then ok. I guess we'll just have to agree to disagree about the prospects for a better understanding of quantum optical experiments, and quantum entanglement.

 

[ThomasT]

Your claim here is completely ill-defined.

I'm somewhat noted for that.

What is "joint intensity" supposed to mean in the context of optics?

We're talking about optical Bell tests, right? I think I phrased it as the 'coincidental photon flux'.

In certain optical Bell tests the coincidence rate is proportional to cos^2(a-b). From your knowledge of quantum optics, do you think that that indicates or requires that something nonlocal or ftl is happening in those experiments?

The joint probability P(AB) is not being modeled as the product of P(A)*P(B) by Bell's equation. Do you disagree?

My thinking has been that it reduces to that. Just a stripped down shorthand for expressing Bell's separability requirement. If you don't think that's ok, then how would you characterize the separability of the joint state (ie., the expression of locality) per Bell's (2)?

 

[JesseM]

3) Statements like this don't do it for me. The goal is to understand the correlations, not keep them mysterious. If you want to think that something nonlocal or ftl kicks in simply because single photons are being detected, or because a polarizer has been moved, or a wave plate adjusted, then ok.

Bell's theorem doesn't depend on the fact that "single photons are being detected", but it does require that each measurement setting can yield one of two binary outcomes akin to "spin-up" and "spin-down". You are free to design your detectors in a classical optics experiment so that they can only yield two outcomes rather than a continuous range of intensities--for example, you design it so that if the intensity of the light that made it through the polarizer was above a certain threshold a red light would go off, and if the intensity was at or below that threshold a green light would go off. Likewise you might design the detector so the probability or a red light going off vs. a green light going off would depend on the reduction in intensity as the light went through the polarizer--say if the intensity was reduced by 70%, there'd be a 70% chance the red light would go off and a 30% chance the green light would go off.

But no matter how you design the experiment, as long as each detector setting can yield only one of two possible results, and the two measurements are made at a spacelike separation, no experiment which obeys the laws of classical optics will violate Bell's inequalities. Do you disagree? If you do, please give specifics on the design of the experiment you are imagining, detailing how the light's polarization and the detector setting determine which of two outcomes occur on each trial (as I did in the two examples above). If you can't fill in these basic details, then your claims that there is an "optical" explanation for Bell-inequality-violating quantum correlations are obviously not very well thought-out.

 

[ThomasT]

There's no way to use the first cos^2 law to derive the second one, whatever ThomasT may think.

I'm just trying to understand the correlation between the angular difference in the polarizer settings and coincidental detection. It doesn't 'seem' mysterious. That is, the optics principle that applies to the observed coincidence count when both polarizers are on one side, would seem to be applicable when there's one polarizer on each side.

 

[ThomasT]

"One to one quantitative correspondence" between what and what? the cos^2 in Malus' law is for the difference between the angle of a polarizer and the polarization angle of a beam hitting it at the same location, the cos^2 in entanglement experiments is for the difference in angles between two polarizers at completely different locations making measurements on different particles.

The cos^2 in Malus Law is the functional relationship between the angular difference of two polarizer settings and the measured intensity of the light transmitted by the analyzing polarizer.

You can demonstrate Malus Law in an optical Bell test by simply taking the polarizer on side A and putting it on side B.

Interestingly, P(AB) remains .5cos^2(a-b) when this is done, and we wouldn't think that anything nonlocal was happening in that situation -- would we?

 

[ThomasT]

To illustrate, consider a standard polarized beam of light. Take the polarization of the light beam to be something other than theta = 0, and offset the polarizer/detector from the light beam on that same coordinate system. It breaks Malus law when you demand arbitrary coordinate choices, even in standard optics. This same demand that is insisted on to model EPR correlations that is also broken in standard optics.

I don't understand what you're saying here.

 

[DrChinese]

DrC,
Perhaps you can be more clear. When you say:
1) If optics were the ruling issue, we would see Product State statistics.

Is this not essentially equivalent to saying, based on optics alone, that given theta = x then 2theta = 2x?, or some linear multiple for all theta. Malus law doesn't work this way even in standard optics.

I don't see using Malus law to show the same behavior pattern as relevant in resolving the issue, but neither does calling a one to one quantitative correspondence only an apparent match make much sense to me. As noted, by itself it doesn't resolve the realism issue, and standard optics allows a greater range of presumptions about how this result might be classical. The simplest of such presumptions being unequivocally ruled out by EPR correlation experiments. Yet perhaps you could be more specific in claiming an exact numerical match is an illusion.

Perhaps the rebuttal should involve the extra constraints BI imposes on possible mechanisms, rather than simply claiming the a quantitative correspondence is an illusion. Because I really don't think you can demonstrate that Malus law, standard optics, allows arbitrary choices of theta that leads to linear polarizer path statistics.

To illustrate, consider a standard polarized beam of light. Take the polarization of the light beam to be something other than theta = 0, and offset the polarizer/detector from the light beam on that same coordinate system. It breaks Malus law when you demand arbitrary coordinate choices, even in standard optics. This same demand that is insisted on to model EPR correlations that is also broken in standard optics.

Yes, I think these issues are fundamentally related. No, I don't think simply pointing out the relationship within standard optics, by itself, represents a resolution to the issue. The fact that it could be interpreted differently within the context of standard optics ignores the extra properties/things relationship constraints that EPR correlation experiments are sensitive to.

The issue is that in standard optics, there is NOT perfect correlation of light beams - even when they are created together with symmetric (or anti-symmetric) polarizations. So as you mention, the "extra properties" are only present in an entangled (EPR) state. There is nothing optically that relates too this and that is why I am trying to drive the point home. Which is that there are no classical optics that have the EPR state present. The EPR state only occurs with a suitable superposition, and there is no classical analog to this. (Specifically, the states must be indistinguishable.)

 

[DrChinese]

I'm just trying to understand the correlation between the angular difference in the polarizer settings and coincidental detection. It doesn't 'seem' mysterious. That is, the optics principle that applies to the observed coincidence count when both polarizers are on one side, would seem to be applicable when there's one polarizer on each side.

Except that it doesn't apply to ordinary streams of identically polarized photon pairs coming from a PDC crystal. According to your ideas, it should. You would predict Entangled State stats (cos^2 theta) and you instead see Product State (.5*(.5+cos^2 theta)). So your prediction is flat out incorrect.

I re-iterate: where is your REFERENCE?

 

[JesseM]

We're talking about optical Bell tests, right? I think I phrased it as the 'coincidental photon flux'.

Please review the context of this exchange. I said "Well, can you present your local optical explanation in detail, either here or on a new thread?" and you replied "It isn't 'my' optical explanation. It's optics." Naturally I took this to imply you thought there could be a local optical explanation for the cos^2(a-b) statistics seen in entanglement experiments, perhaps one involving Malus' law (which can indeed be derived from classical electromagnetism, a completely local theory). Did I misunderstand? Are you not claiming that the statistics can be explained in terms of local properties that travel along with the two beams (or the individual photons) that were assigned to them by the source?

In certain optical Bell tests the coincidence rate is proportional to cos^2(a-b). From your knowledge of quantum optics, do you think that that indicates or requires that something nonlocal or ftl is happening in those experiments?

It does require that if we adopt a "realist" view of the type I discussed in post #101 of the Understanding Bell's Logic thread, and if we assume each measurement has a single unique outcome (so many-worlds type explanations are out), and if the experiment meets various observable requirements like sufficiently high detector efficiency and a spacelike separation between measurements.

The joint probability P(AB) is not being modeled as the product of P(A)*P(B) by Bell's equation. Do you disagree?

My thinking has been that it reduces to that.

Yes, of course I disagree, you're just totally misunderstanding the most basic logic of the proof which is assuming a perfect correlation between A and B whenever both experimenters choose the same detector setting. It's really rather galling that you make all these confident-sounding claims about Bell's proof being flawed when you fail to understand something so elementary about it! Could you maybe display a tiny bit of intellectual humility and consider the possibility that it might not be that the proof itself is flawed and that you've spotted a flaw that so many thousands of smart physicists over the years have missed, that it might instead be you are misunderstanding some aspects of the proof?

If you want an example where two variables are statistically dependent in their marginal probabilities but statistically independent when conditioned on some other variable, you might consider the numerical example I provided in this post, where P(T,U) is not equal to P(T)*P(U) but P(T,U|V) is equal to P(T|V)*P(U|V):

in your example there seem to be two measured variables, T which can take two values {received treatment A, received treatment B} and another one, let's call it U, which can also take two values {recovered from disease, did not recover from disease}. Then there is also a hidden variable we can V, which can take two values {large kidney stones, small kidney stones}. In your example there is a marginal correlation between variables T and U, but there is still a correlation (albeit a different correlation) when we condition on either of the two specific values of V. So, let me modify your example with some different numbers. Suppose 40% of the population have large kidney stones and 60% have small ones. Suppose those with large kidney stones have an 0.8 chance of being assigned to group A, and an 0.2 chance of being assigned to group B. Suppose those with small kidney stones have an 0.3 chance of being assigned to group A, and an 0.7 chance of being assigned to B. Then suppose that the chances of recovery depend only one whether one had large or small kidney stones and is not affected either way by what treatment one received, so P(recovers|large kidney stones, treatment A) = P(recovers|large kidney stones), etc. Suppose the probability of recovery for those with large kidney stones is 0.5, and the probability of recovery for those with small ones is 0.9. Then it would be pretty easy to compute P(treatment A, recovers, large stones)=P(recovers|treatment A, large stones)*P(treatment A, large stones)=P(recovers|large stones)*P(treatment A, large stones)=P(recovers|large stones)*P(treatment A|large stones)*P(large stones) = 0.5*0.8*0.4=0.16. Similarly P(treatment A, doesn't recover, small stones) would be P(doesn't recover|small stones)*P(treatment A|small stones)*P(small stones)=0.1*0.3*0.6=0.018, and so forth.

In a population of 1000, we might then have the following numbers for each possible combination of values for T, U, V:

1. Number(treatment A, recovers, large stones): 160
2. Number(treatment A, recovers, small stones): 162
3. Number(treatment A, doesn't recover, large stones): 160
4. Number(treatment A, doesn't recover, small stones): 18
1. Number(treatment B, recovers, large stones): 40
2. Number(treatment B, recovers, small stones): 378
3. Number(treatment B, doesn't recover, large stones): 40
4. Number(treatment B, doesn't recover, small stones): 42

If we don't know whether each person has large or small kidney stones, this becomes:

1. Number(treatment A, recovers) = 160+162 = 322
2. Number(treatment A, doesn't recover) = 160+18 = 178
3. Number(treatment B, recovers) = 40+378 = 418
4. Number(treatment B, doesn't recover) = 40+42=82

So here, the data shows that of the 500 who received treatment A, 322 recovered while 178 did not, and of the 500 who received treatment B, 418 recovered and 82 did not. There is a marginal correlation between receiving treatment B and recovery: P(treatment B, recovers)=0.418, which is larger than P(treatment B)*P(recovers)=(0.5)*(0.74)=0.37. But if you look at the correlation between receiving treatment B and recovery conditioned on large kidney stones, there is no conditional correlation: P(treatment B, recovers|large stones) = P(treatment B|large stones)*P(recovers|large stones) [on the left side, there are 400 people with large stones and only 40 of these who also received treatment B and recovered, so P(treatment B, recovers|large stones) = 40/400 = 0.1; on the right side, there are 400 with large stones but only 80 of these received treatment B, so P(treatment B|large stones)=80/400=0.2, and there are 400 with large stones and 200 of those recovered, so P(recovered|large stones)=200/400=0.5, so the product of these two probabilities on the right side is also 0.1] The same would be true if you conditioned treatment B + recovery on small kidney stones, or if you conditioned any other combination of observable outcomes (like treatment A + no recovery) on either large or small kidney stones.

If you like I could also show you how something similar would be true in my scratch lotto example, which is even more directly analogous to the situation being considered in Aspect-type experiments.

If you don't think that's ok, then how would you characterize the separability of the joint state (ie., the expression of locality) per Bell's (2)?

I would characterize it in terms of A and B being statistically independent only when conditioned on the value of the hidden variable λ. They are clearly not statistically independent otherwise, and Bell makes it explicit that he assumes there is a perfect correlation between their values when both experimenters choose the same detector setting. For example, in the introduction to the original paper he says:

Since we can predict in advance the result of measuring any chosen component of $$\sigma_2$$, by previously measuring the same component of $$\sigma_1$$, it follows that the result of any such measurement must actually be predetermined.

Likewise in http://cdsweb.cern.ch/record/142461/files/198009299.pdfpapers Bell writes on p. 11:

Let us summarize once again the logic that leads to the impasse. The EPRB correlations are such that the result of the experiment on one side immediately foretells that on the other, whenever the analyzers happen to be parallel. If we do not accept the intervention on one side as a causal influence on the other, we seem obliged to admit that the results on both sides are determined in advance anyway, independent of the intervention on the other side, by signals from the source and by the local magnet setting.

If the value of measurement A "immediately foretells" the value of measurement B when the settings on both sides are the same, that means there's a perfect correlation between the value of A and the value of B when conditioned only on the fact that both sides used the same setting (and not conditioned on any hidden variables)--do you disagree?

 

[JesseM]

I'm just trying to understand the correlation between the angular difference in the polarizer settings and coincidental detection. It doesn't 'seem' mysterious.

Well, you are going to have to do some precise reasoning rather than just relying on feelings about how things "seem" if you want to understand Bell's arguments.

That is, the optics principle that applies to the observed coincidence count when both polarizers are on one side, would seem to be applicable when there's one polarizer on each side.

If you are doing an experiment which matches the condition of the Bell inequalities that says each measurement must yield one of two binary results (rather than a continuous range of intensities), then even if "both polarizers are on one side" it would be impossible to reproduce the cos^2 relationship between the angles of the two polarizers in classical optics, despite the fact that Malus' law applies in classical optics. Do you disagree? In post #896 I outlined some ways you might design a detector to yield one of two binary outcomes in an experiment based on classical optics:

You are free to design your detectors in a classical optics experiment so that they can only yield two outcomes rather than a continuous range of intensities--for example, you design it so that if the intensity of the light that made it through the polarizer was above a certain threshold a red light would go off, and if the intensity was at or below that threshold a green light would go off. Likewise you might design the detector so the probability or a red light going off vs. a green light going off would depend on the reduction in intensity as the light went through the polarizer--say if the intensity was reduced by 70%, there'd be a 70% chance the red light would go off and a 30% chance the green light would go off.

But no matter how you design your classical detector to give one of two binary outcomes based on how much light passes through it, you can never get a violation of the Bell inequalities in classical optics.

 

[my_wan]

"One to one quantitative correspondence" between what and what? the cos^2 in Malus' law is for the difference between the angle of a polarizer and the polarization angle of a beam hitting it at the same location, the cos^2 in entanglement experiments is for the difference in angles between two polarizers at completely different locations making measurements on different particles. There's no way to use the first cos^2 law to derive the second one, whatever ThomasT may think.

Of course the polarizer at the same location in the classic optics case, with no path references for individual photons. That's one of the reasons EPR correlations are sensitive to certain realism claims that standard optics is not. The quantitative correspondence results when you apply the same same location rules to the photon polarizers interactions plus standard conservation requiring photon pairs be anticorrelated, if you insist on rotational invariance at every level. These two conditions lead to an apparent contradiction between the statics we invariable measure and the statistics and the statistics we apparently would have gotten using any other choice of settings besides what we actually measured, if the path through the polarizer was a real property of the photon.

Why a "greater range of presumptions"? Standard optics can be derived from Maxwell's laws, which is a perfect example of a local realist theory of physics, so Bell's theorem definitely applies to anything in optics (and it's impossible to use classical optics to get a violation of Bell inequalities).

The "greater range of presumptions" allowed is because the standards optics case alone does not have a reference case to question (in principle) how this set of photons would have been detected had we chosen detector settings differently. Maxwell's equations also described fields, leaving the particle behavior more or less out. How would you define the set of all individual variables such a field can define?

Note the original EPR paper hinged on conservation law. The randomized polarizations of the emitter alone statistically demands rotational invariance, irrespective of any underlying mechanism. Thus Malus law + conservation + statistical rotational invariance does lead to the same statistical contradictions.

We are left with a *fundamentally* statistical theory in which statistical outcomes can be deterministically determined in some cases, but lacks variables that can even in principle explain how the outcomes are predetermined.

Malus' law is only based on the difference in angle between the beam and the polarizer, so it doesn't get violated depending on how your coordinate system defines the angle of the beam. Are you suggesting otherwise?

EXACTLY! Malus law is dependent only on the angle difference. Now note: A randomly polarized emitter physically must, irrespective of and underlying or lack of mechanism, be rotational invariant. So as long as 3 rules always apply, Malus law, rotational invariance, and conservation law, then BI violations must occur. If, statistically, rotational invariance applies, as it physically must for a randomly polarized beam, it does not mean the individual events defined by individual detections must also be rotational invariant, any more than Malus law.

I'm not entirely convinced by my own arguments, but I would appreciate more than hand waving the issues. Now, to argue against this, two things would be acceptable and appreciated:
1) Reject that rotational invariance can be induced simply by randomizing the polarization of the emitter, and explain why.
2) Accepting 1), explain why, if Malus law is dependent solely on angle difference and rotational invariance is dependent solely on randomized polarizations (not individual detection events), it could be expected that EPR correlations should depend on more than just the angle difference between the detector pairs.

You could also try to show that Malus law can be applied to any coordinate rotation rather than just a difference in rotation. You could also try to explain why Malus law + conservation + statistical rotational invariance does not lead to the same statistical contradictions.

 

[JesseM]

The quantitative correspondence results when you apply the same same location rules to the photon polarizers interactions plus standard conservation requiring photon pairs be anticorrelated, if you insist on rotational invariance at every level.

Again, "quantitative correspondence" between what and what? Are you claiming that if we "apply the same same location rules to the photon polarizers interactions plus standard conservation requiring photon pairs be anticorrelated", that uniquely leads us to the statistics seen in QM? If so, what "same location rules" are you talking about, given that Malus' law deals with continuous decreases in intensity rather than the binary fact about whether a photon passes through a polarizer?

Note the original EPR paper hinged on conservation law. The randomized polarizations of the emitter alone statistically demands rotational invariance, irrespective of any underlying mechanism. Thus Malus law + conservation + statistical rotational invariance does lead to the same statistical contradictions.

Well, see above, it's not clear to me what you mean by "Malus law" in the context of detecting individual photons rather than looking at how the intensity of an electromagnetic wave changes when it passes through a polarizer.

 

[my_wan]

Again, "quantitative correspondence" between what and what? Are you claiming that if we "apply the same same location rules to the photon polarizers interactions plus standard conservation requiring photon pairs be anticorrelated", that uniquely leads us to the statistics seen in QM? If so, what "same location rules" are you talking about, given that Malus' law deals with continuous decreases in intensity rather than the binary fact about whether a photon passes through a polarizer?

I'm only looking at how a photon responds to the polarizer it comes in contact with irrespective of what a distant correlated photon does, which requires Malus law in all cases. This also entails that a detector offset from the default photon polarization has some likelihood of passing that photon 'as if' it possessed that polarization. These odds defined by Malus law. Now to add an assumption: these photons have properties that predetermine how they will respond to any polarizer setting, such that an identical twin photon would have responded to a polarizer with the same arbitrary setting the same way. Opposite for anti-twins. Now, as long as the properties of the photons in the beam is, as a group, randomized such that rotational invariance must be maintained, and Malus law (with relative offsets) is required for all cases, the predeterminism assumption leads to BI violations, irrespective of any other consideration.

Here's the challenge: you CANNOT construct a local deterministic variable set, independent of QM, BI, etc., that respects Malus law for any arbitrary setting and rotational invariance without violating BI. You will invariably be stuck with the same relative offset requirements that Malus law is predicated on. This results without any reference to QM whatsoever. The effect may be local, at the point where photon meets polarizer, but the counterfactual requirement that the photon polarizer interaction is predetermined in all cases is effectively equivalent to what an anti-twin is doing light years away.

Are you seeing the difficulty here, when the impossibility logic is turned on its head? The same impossibility Bell demonstrated also points to an impossibility of maintaining Malus law without violating BI. Of course, as you noted, Malus law can be derived from Maxwell's equations, which is a classical field theory. So, unless you can deny the validity of the challenge, what does this say about the "reality" of classical fields? Perhaps the deterministic variables are transfinite? I don't know, but if you can successfully reject the validity of the challenge I'll be indebted to you.

 

[DrChinese]

Are you seeing the difficulty here, when the impossibility logic is turned on its head? The same impossibility Bell demonstrated also points to an impossibility of maintaining Malus law without violating BI. Of course, as you noted, Malus law can be derived from Maxwell's equations, which is a classical field theory. So, unless you can deny the validity of the challenge, what does this say about the "reality" of classical fields? .

Yes, this is true (about Malus). However, this has nothing to do with some kind of "challenge" or impossiblity. Your logic does not work:

Malus-> Bell Inequality violation
QM-> Malus-> Bell Inequality violation

This is perfectly reasonable.

 

[my_wan]

Yes, this is true (about Malus). However, this has nothing to do with some kind of "challenge" or impossiblity. Your logic does not work:

Malus-> Bell Inequality violation
QM-> Malus-> Bell Inequality violation

This is perfectly reasonable.

Not real sure I follow. Not even sure how to guess what you intended to say. My best guess is your saying "QM-> Malus-> Bell Inequality violation" is "perfectly reasonable", but still can't grok your intended meaning with any confidence.

If your summing up what I said as "Malus-> Bell Inequality violation" it's more than a little overly simplified, as is the implicit QM and BI issues. Are you saying that "Malus-> Bell Inequality violation" doesn't work, while "QM-> Malus-> Bell Inequality violation" does?

What I'm saying is that, even if you forget everything you know about QM, and merely try to construct a local realistic variable set that respects Malus law without violating BI, you can't do it. It is you who keeps insisting the similarity between Malus law and QM is an illusion, yet here I am presumptuously interpreting you to say Malus law is a QM law.

Here's an example of what you can't do. Define a set of photons with predefined properties which entails that 50% of all randomly polarized photons are predetermined to pass a polarizer at any angle. Then require the predetermined photon paths to switch paths through the polarizer according to Malus law as you rotate the polarizer. Now try and get this same predefined set of photons to continue honoring Malus law when you pick a pair of counterfactual detector setting in which neither setting is 0. It will not work, and this doesn't even involve correlations, only paths taken by a predefined set of photons through a variable polarizer setting. Without correlation you don't have a uniquely QM phenomena, yet BI violation persist in simple classical paths through a polarizer.

Does it now make sense why the QM requirement (I think) you imposed is not necessary for BI? Not even correlations are required, only assumptions of classical paths. Of course Maxwell's equations, in spite of being a classical construct, has no requirement of presuming photon trajectories represent a classical path, due to its field theoretic construction.

 

[JesseM]

I'm only looking at how a photon responds to the polarizer it comes in contact with irrespective of what a distant correlated photon does, which requires Malus law in all cases.

How does Malus' law apply to individual photons, though? The classical version of Malus' law requires uniformly polarized light with a known polarization angle, are you talking about a photon that's known to be in a polarization eigenstate for a polarizer at some particular angle? In that case, whatever the angle v of the eigenstate, I think the probability the photon would pass through another angle at angle a would be cos^2(v-a). But when entangled photons are generated, would they be in such a known polarization eigenstate? If not it seems like you wouldn't be able to talk about Malus' law applying to individual members of the pair.

Of course, as you noted, Malus law can be derived from Maxwell's equations, which is a classical field theory. So, unless you can deny the validity of the challenge, what does this say about the "reality" of classical fields? Perhaps the deterministic variables are transfinite? I don't know, but if you can successfully reject the validity of the challenge I'll be indebted to you.

But with electromagnetic waves in Maxwell's equations there's no probabilities involved, Malus' law just represents a deterministic decrease in intensity. So there's no case where two detectors at different angles a and b have a probability cos^2(a-b) of opposite results, including the fact that they give opposite results with probability 1 with the detectors at the same angle. This is true even if you design the detectors to give one of two possible outputs depending on the decrease in intensity, as I suggested in post #896 to ThomasT. So no violations of BI and no reason Maxwell's laws can't be understood as a local realist theory, so I'm not sure why you have a problem with the reality of classical fields.

 

[DrChinese]

Not real sure I follow. Not even sure how to guess what you intended to say. My best guess is your saying "QM-> Malus-> Bell Inequality violation" is "perfectly reasonable", but still can't grok your intended meaning with any confidence.

If your summing up what I said as "Malus-> Bell Inequality violation" it's more than a little overly simplified, as is the implicit QM and BI issues. Are you saying that "Malus-> Bell Inequality violation" doesn't work, while "QM-> Malus-> Bell Inequality violation" does?

What I'm saying is that, even if you forget everything you know about QM, and merely try to construct a local realistic variable set that respects Malus law without violating BI, you can't do it. It is you who keeps insisting the similarity between Malus law and QM is an illusion, yet here I am presumptuously interpreting you to say Malus law is a QM law.

Here's an example of what you can't do. Define a set of photons with predefined properties which entails that 50% of all randomly polarized photons are predetermined to pass a polarizer at any angle. Then require the predetermined photon paths to switch paths through the polarizer according to Malus law as you rotate the polarizer. Now try and get this same predefined set of photons to continue honoring Malus law when you pick a pair of counterfactual detector setting in which neither setting is 0. It will not work, and this doesn't even involve correlations, only paths taken by a predefined set of photons through a variable polarizer setting. Without correlation you don't have a uniquely QM phenomena, yet BI violation persist in simple classical paths through a polarizer.

Does it now make sense why the QM requirement (I think) you imposed is not necessary for BI? Not even correlations are required, only assumptions of classical paths. Of course Maxwell's equations, in spite of being a classical construct, has no requirement of presuming photon trajectories represent a classical path, due to its field theoretic construction.

OK, ask this: so what if Malus rules out local realistic theories per se? You are trying to somehow imply that is not reasonable. Well, it is.

We don't live in a world respecting BIs while we do live in one which Malus is respected. There is no contradiction whatsoever. You are trying to somehow say Malus is classical but it really isn't. It is simply a function of a quantum mechanical universe. So your logic needs a little spit polish.