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Disconnect With Inequality Realism Assumption And Bells' Lambda

  1. Sep 16, 2014 #1


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    Bell, QM Ideas - Science 177 1972 :" Strictly, however. a hidden variable theory could be non-deterministic; the hidden variable could evolve randomly (possibly even discontinuously) so that their values at one instant do not specify their values at the next instant"
    From the locality assumption, (EPR on non-locality: " No reasonable definition of reality could be expected to permit this")
    With no assumption of determinism or of classical behavior with probabilities p(ab|xy) that satisfy the locality decomposition
    S = (a0b0+(a0b1) +(a1b0) - (a1b1) ≤ 2
    Bell on realism: "That there should be definite outcomes possible for counter factual settings"
    But are there formulations for predetermined values equivalent to those for locality ?
    So given Bells definition of lambda above it seems you could expect that S = 2√2 and the QM predicted correlations and inequality violation. And that they suggest local non realism explanation.
  2. jcsd
  3. Sep 16, 2014 #2


    Staff: Mentor

    Without answering your question at the end, that is indeed correct.

    Both Feynman's Sum Over Histories and Consistent Histories are hidden variable theories of that type.

    But its not what is usually thought of as hidden variable.

    I don't believe anything in QM suggests local non realism, local realism (in fact Bells Theorem strongly suggests otherwise - but I don't want to get into it because the answer depends on what you mean by Local Realism eg MWI can be viewed as local realistic - but not counterfactual - which is why the issue is subtle), non local realism, or any of the myriad of interpretations floating around - that's why they are called interpretations.

    But regarding your specific question if what Bell wrote suggests whatever - I will let others get into that - its not my thing.

    Last edited: Sep 16, 2014
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