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Bell's theorem - for or against Hidden Variables?
(09-24-2016, 05:59 PM)Thomas Ray Wrote: So I have just finished a marvelous new paper by Hess, De Raedt and Michielsen, that illustrates exactly what I mean, by the demarcation of science and philosophy.  Attached.

The paper https://arxiv.org/abs/1605.05237 (de Raedt, Michielsen and Hess) exploits a well-known loophole, namely the coincidence loophole, to simulate the singlet correlations in an EPR-B experiment in a completely classical way. The idea is to let each particle experience a time-delay when arriving at the detector which depends both on hidden variables carried in the particle and the setting which has been applied to the detector. Consequently, the time interval between the detection times of the two particles depends on both settings and on the hidden variables carried in the particles. Now suppose we use a "coincidence window", that is we reject all particle pairs for which the time interval between detection times is larger than some threshhold. The particle pairs which are "post-selected" in this way are not a random sample of all particle pairs. Whether or not a pair survives depends on *both* settings and on hidden variables carried by the particles.

It has been known for a long time how one can use this trick to simulate the EPR-B correlations and thereby violate Bell inequalites. Hans de Raedt et al. know this well, and refer for instance to Larsson and Gill (2004). Possibly the first who discovered this was Pascazio (1986, Phys.Letters A, "Time and Bell-type inequalities").

The authors claim that they have simulated a "loophole free" experiment, but that is simply not true. The post-selection which they perform creates the loophole opened up by what is loosely called the "coincidence loophole" ... and which is ruled out in the best experiments by a more stringent experimental protocol.

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RE: Bell's theorem - for or against Hidden Variables? - by gill1109 - 09-25-2016, 02:17 PM

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