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DrChinese said:You are correct that "realism" is not mentioned. This definitely follows Norsen's reasoning. I am surprised to see Cavalcanti in the list of authors, as he had recently written about "local realism" in the same vein as I. So you may be correct that the tide has changed.
bohm2 said:Actually, even Norsen himself argues in his paper that a particular notion of 'realism' is required for Bell's theorem; that is, the notion of "metaphysical realism" or the existence of an external world “out there” whose existence and identity is independent of anyone’s awareness:
http://arxiv.org/pdf/quant-ph/0607057v2.pdf
I think there is actually hardly any disagreement, mostly just a change in language. There seem to be two major meanings of "realism".
The first is what Norsen calls "metaphysical realism". This is needed for a Bell test in the sense that one must agree that results at spacelike separation are real. So this meaning of "realism" is a prerequisite for local determinism, and in this sense "local realism" is redundant. Apart from Norsen, I found agreement also in http://arxiv.org/abs/0706.2661 (footnote 16), http://arxiv.org/abs/0911.3814 (p12). There's a similar idea in http://arxiv.org/abs/quant-ph/0509061 (p11).
The second is what DrChinese is calling "counterfactual definiteness". I think everyone also agrees that the class of theories that pass a Bell test can be completely generated from local deterministic theories, so that proving the inequality for a counterfactual definite theory proves it for the entire class. The only reason one might not like this terminology is that there isn't enough consensus on what "counterfactual definiteness" means to agree on whether the local stochastic theories that pass a Bell test are also "counterfactual definite". Nonetheless, it is agreed that the local deterministic theories are key to defining this class, since the "local polytope" and whether a Bell inequality is tight or not all depend on local deterministic theories. An example of the local polytope generated by local deterministic theories is drawn in Fig. 1 of http://arxiv.org/abs/1405.7321. Then the only controversy is whether one wants to consider as "real" the local deterministic theories that can in principle underlie a local stochastic theory, which is why Gill writes uses language like "in a mathematical sense" and "or at least may be constructed" when describing realism in http://arxiv.org/abs/1207.5103. So if we define "realism" as "may be constructed from local deterministic theories", Norsen would like to be able to say that this realism may or may not be real. Is that's a sweet concession from a realist? :)
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