1. There is no "locality assumption" in Bell's derivation of his inequalities. None whatsoever, despite repeated noises about "locality".
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- Secondly, setting indepdendence is irrelevant for the derivation anyway because one could eliminate hidden variables (local or non-lcoal) completely and still proceed to derive the inequality, since the expectation value of the paired product can be calculated for any valid probability measure. This has been clearly explained in this post.
and after factorizing out
The second term on the right is
2. The counterfactual definiteness assumption invoked by Bell applies to QM as well. Bell himself uses it on page 1 to make a QM argument.
- - Counterfactual Definiteness is defined as: Wikipedia: In quantum mechanics, Counterfactual definiteness (CFD) is the ability to speak meaningfully of the definiteness of the results of measurements that have not been performed (i.e. the ability to assume the existence of objects, and properties of objects, even when they have not been measured).
Gill (http://arxiv.org/pdf/1207.5103v6.pdf): Its formulation refers to outcomes of measurements which are not actually performed, so we have to assume their existence, alongside of the outcomes of those actually performed: the principle of realism, or more precisely, counterfactual definiteness.
http://arxiv.org/pdf/1007.4281.pdf: the assumption that a measurement that was not performed had a single definite result..
- Bell's 2nd and 3rd sentence in paragraph 2 of page 1, applies CFD to quantum mechanics as follows: If Alice measures along "a" and obtained +1, then if Bob were to measure the sister particle along "a" he must obtain -1. Clearly, Bell believes and QM states that the measurement that was not performed has a single definite value. In fact, CFD applies to any theory that makes predictions. Any suggestion otherwise reflects lack of thinking ability, as it can easily shown that a prediction for an experiment which ends up not being done, is counterfactually definite. No theory is immune to this, including QM.
3. Bell's inequality relates one actual measurement, to two counterfactual measurements which could have been done but weren't.
- - Bell invokes CFD in his derivation starting on Page 406 where he states that "it follows that c is another unit vector". Note, we have a pair of particles, one is measured along "a", the other is measured along "b". Bell says it follows that "c" is another unit vector, but we don't have any other particles to measure along "c". Therefore "c" is a counterfactual axis (what we could have measured but didn't). This is also revealed in the above derivation, by the use of the same index
- Therefore Bell's inequality is a relationship between one actual expectation value
4. Bell's inequality can not be derived if we do not assume counterfactual results, but instead use actual independent measurements .
- - It does not apply to three actual expectation values
Therefore, the following is also poppycock:
Starting from realism and Einstein locality, we can prove Bell's inequality.
Bell's inequality is violated.
Thus, "local realism" (Einstein-local realism would be more accurate) is falsified.
If locality is not required to obtain the inequalities, there is no reasonable way for a reasonable person to conclude that violations of the inequalities falsifies locality. [emphasis on reasonable] Thus poppycock.