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arXiv · 1305.4671

Not all entangled states violate Leggett's crypto-nonlocality

Cyril Branciard
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Abstract

This note is a reply to M. Navascués' claim that "all entangled states violate Leggett's crypto-nonlocality" [arXiv:1303.5124v2]. I argue that such a conclusion can only be reached if one introduces additional assumptions that further restrict Leggett's notion of "crypto-nonlocality". If a contrario one sticks only to Leggett's original axioms, there exist entangled states whose correlations are always compatible with Leggett's crypto-nonlocality---which is thus a genuinely different concept from quantum separability. I clarify in this note the relation between these two notions, together also with Bell's assumption of local causality.

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Cyril Branciard. 2013-10-18. Not all entangled states violate Leggett's crypto-nonlocality. https://doi.org/10.1103/physreva.88.042113

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