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arXiv · 2011.04111

On Possibilistic Conditions to Contextuality and Nonlocality

Leonardo Santos·Barbara Amaral
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Abstract

Contextuality and nonlocality are non-classical properties exhibited by quantum statistics whose implications profoundly impact both foundations and applications of quantum theory. In this paper we provide some insights into logical contextuality and inequality-free proofs. The former can be understood as the possibility version of contextuality, while the latter refers to proofs of quantum contextuality/nonlocality that are not based on violations of some noncontextuality (or Bell) inequality. The present work aims to build a bridge between these two concepts from what we call possibilistic paradoxes, which are sets of possibilistic conditions whose occurrence implies contextuality/nonlocality. As main result, we demonstrate the existence of possibilistic paradoxes whose occurrence is a necessary and sufficient condition for logical contextuality in a very important class of scenarios. Finally, we discuss some interesting consequences arising from the completeness of these possibilistic paradoxes.

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Leonardo Santos, Barbara Amaral. 2020-11-08. On Possibilistic Conditions to Contextuality and Nonlocality. https://doi.org/10.1103/physreva.104.022201

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