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I About Bell's disproof

  1. May 13, 2017 #1
    Hello, I've been conducting a little search on my own and found there seems to be a community of physicists/philosophers that don't accept Bell's theorem as valid.
    There are are two types of loopholes : fundamental theoretical ones and experimental loopholes.
    I'm particularly interested in the the first kind of arguments and would like to know, in spite of personal beliefs, if somebody have an objective opininon about this and how serious the people of this "community" is taken by the rest of scientific community.
     
    Last edited: May 13, 2017
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  3. May 13, 2017 #2

    phinds

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    This is a contradiction in terms
     
  4. May 13, 2017 #3

    atyy

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    The theoretical loopholes or assumptions (superdeterminism, non-realism, single outcome, etc ...) are standard and well accepted.

    https://arxiv.org/abs/1303.2849
    Bell nonlocality
    Nicolas Brunner, Daniel Cavalcanti, Stefano Pironio, Valerio Scarani, Stephanie Wehner

    "The point of this discussion is that an experiment "closing" the locality loophole should be designed in such a way that any theory salvaging locality by exploiting weaknesses of the above type should be suciently conspiratorial and contrived that it reasonably not worth considering it."
     
    Last edited: May 13, 2017
  5. May 13, 2017 #4

    DrChinese

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    Well, it's a small community. :smile:

    All it would take is a single counterexample to wreck Bell's Theorem. And yet, over 50 years later, there are none.

    Please note additionally: In the past 20 years, there have been many thousands of different experimental disproofs of local realism. Bell started it, but the number of concurring experiments is staggering. Many use techniques very dissimilar to the Bell approach.

    Basically, to deny Bell is to deny that there is such thing as an entangled quantum state.
     
  6. May 13, 2017 #5
    There are some freaks around Joy Christian, one of them a former activist from the Sci.Physics.Foundations USENET group, who has created a copy of this as his own forum, which became their meeting place. Joy Christian has at least some mathematical education, but is unable to acknowledge his quite elementary errors. What surprises me is that he has been even found some supporters. But this is interesting mainly from a sociological point of view, and in no way evidence that he has really found something.
     
  7. May 16, 2017 #6
    It may be small but they seem to support each other and are very convinced of what they say.
    It is interesting but not all of them are freaks. Some of them publish papers in respectable journals.
     
  8. May 16, 2017 #7

    stevendaryl

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    Are you talking about Joy Christian's supporters, or more generally people who question Bell's proof? Joy Christian's supporters don't include any reputable physicists, as far as I know.
     
  9. May 17, 2017 #8
    No, I'm not talking about Joy Christian and supporters. I wouldn't mind about those kind of things. I'm talking about people who, like I said, seem to be serious and even sometimes (not allways) publish in respectable peer review journals. According to what have been said here, it is a small group and it seems the rest of the physics community don't pay much attention to them. I wonder if it is worthwhile trying to explain where and why their arguments are not good even some of them are just wrong. I just wrote a letter to editor about one such article, I don't know if it will be publish.
     
  10. May 17, 2017 #9

    stevendaryl

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    I'm not sure what you're asking: Are you asking whether it's worthwhile in Physics Forums to discuss why he's wrong?
     
  11. May 17, 2017 #10
    No, I'm asking to Physics Forums whether it is worthwhile to respond to those people writing articles in journals refuting their allegations
     
  12. May 17, 2017 #11

    Nugatory

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    It's hard to answer a question like that in the abstract. What would be an example of an article from a reasonably respectable journal that comes from a member of this "community of physicists/philosophers that don't accept Bell's theorem as valid"?
     
  13. May 17, 2017 #12

    vanhees71

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    Well, if there's an obvious errorneous article in a journal, one should write a comment about it. Of course, it will be peer reviewed and carefully checked whether the claim of error is justified or not. That's at least common practice in the "hard sciences".

    On the other hand, I'm not sure, how this is handled in the "soft sciences", particularly philosophy. I guess in these subjects you'd write comments after comments and commenting these comments in an endless regression. SCNR.
     
  14. May 17, 2017 #13

    phinds

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    Yes, and it would FEEL endless long before it ended. :smile:
     
  15. May 17, 2017 #14

    Nugatory

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    When you speak of "not accepting Bell's theorem as valid" that can mean any of several positions:
    1) There is an error in Bell's proof, so that Bell's inequality does not follow from the starting assumptions. This position is outright crackpottery.
    2) Bell's proof is correct (so Bell's inequality does indeed follow from the starting assumptions) but the experiments demonstrating that quantum mechanics violates the inequality are not conclusive because of various loopholes. This position has become less and less tenable as the experiments have become better and have closed more loopholes; holding it now is very close to outright crackpottery.
    3) Because Bell's proof is correct and the experimental results are valid quantum mechanics does not meet Bell's starting assumptions, but these assumptions do not cover all possible local and realistic theories so the conclusion "no local realistic hidden variable theory can reproduce the results of QM" is still not valid. In the absence of a candidate theory, this position generally leads to a sterile debate about what is meant by "local" and "realistic".
    4) The universe is superdeterministic in a way that generates all observed experimental results. This proposition is not falsifiable, but carries a fairly high implausibility factor.

    Unless you have had the misfortune to stumble into a den of Joy Christianites, chances are the debate you're seeing is of the #3 variety.
     
    Last edited: May 17, 2017
  16. May 17, 2017 #15
    In a "publish or perish" world, why not? An article in a good journal "refuting" Bell's theorem means a good chance for your answer to be published in the same journal.
     
  17. May 17, 2017 #16

    atyy

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    As Nugatory wrote, you have to be more specific. Which researchers and which papers are you talking about?
     
  18. May 17, 2017 #17
    J. Christian, Local causality in a Friedmann–Robertson–Walker spacetime, Annals of Physics (2016), Volume 373, October 2016, Pages 67–79 doi:10.1016/j.aop.2016.06.021 http://www.sciencedirect.com/science/article/pii/S0003491616300975
    It was already visible, but later withdrawn.
     
  19. May 17, 2017 #18
    - "Is the Contextuality Loophole Fatal for the Derivation of Bell Inequalities?" in Foundations of physics
    - "
    Possible experience: From Boole to Bell" in Europhysics Letters

    To name only two but threre many more and they seem to cite every article that refutes Bell no matter the reassons

    Exactly they generally are of type 3 you mentioned, attacking the probabilistic model
     
    Last edited: May 17, 2017
  20. May 17, 2017 #19

    atyy

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    Nieuwenhuizen is a serious physicist, but of course, his work is not necessarily correct.
    The other group of Hess, Michielsen, and De Raedt is generally fringe, which of course doesn't mean their work is wrong.
    Personally, I would not spend any time reading the above papers.

    There are two lines that have some credit

    1) trying to redefine or more generalize the notion of "explanation", so that in this more general sense than that of classical probability, one may say that a local explanation of quantum mechanics is possible. Some of these approaches are discussed by Cavalcanti and Lal in On modifications of Reichenbach's principle of common cause in light of Bell's theorem https://arxiv.org/abs/1311.6852.

    2) Bell's original derivation assumed that each run of the experiment was an independent preparation. If this is not true, how tightly do the violation of Bell inequalities at spacelike separation constrain local realism?

    https://arxiv.org/abs/quant-ph/0110137
    Accardi contra Bell (cum mundi): The Impossible Coupling
    Richard D. Gill

    https://arxiv.org/abs/quant-ph/0205016
    Quantum nonlocality, Bell inequalities and the memory loophole
    Jonathan Barrett, Daniel Collins, Lucien Hardy, Adrian Kent, Sandu Popescu

    https://arxiv.org/abs/1108.2468
    Asymptotically optimal data analysis for rejecting local realism
    Yanbao Zhang, Scott Glancy, Emanuel Knill

    https://arxiv.org/abs/1303.7464
    Efficient quantification of experimental evidence against local realism
    Yanbao Zhang, Scott Glancy, Emanuel Knill
     
    Last edited: May 17, 2017
  21. May 17, 2017 #20

    DrChinese

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    Each person must decide whether "Bell is wrong" papers are worth their time to read or refute. I keep a list of about 50 "denier" papers, and that is hardly complete. So analyzing each in detail for "errors" is quite a time consuming venture.

    So I just look at each to see if they can meet what I call the "DrChinese challenge". Which is: if there are counterfactual outcomes at various measurement settings, what are they? In other words: if there is objective realism a la EPR, one should be able to identify the hypothetical values that would have been obtained if a different measurement pair had been chosen. Barring an answer to that consistent with experiment, it's a waste of time as far as I am concerned.
     
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