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arXiv · 1209.0112

Twin inequality for fully contextual quantum correlations

Adan Cabello
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Abstract

Quantum mechanics exhibits a very peculiar form of contextuality. Identifying and connecting the simplest scenarios in which more general theories can or cannot be more contextual than quantum mechanics is a fundamental step in the quest for the principle that singles out quantum contextuality. The former scenario corresponds to the Klyachko-Can-Binicioglu-Shumovsky (KCBS) inequality. Here we show that there is a simple tight inequality, twin to the KCBS, for which quantum contextuality cannot be outperformed. In a sense, this twin inequality is the simplest tool for recognizing fully contextual quantum correlations.

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Adan Cabello. 2012-09-01. Twin inequality for fully contextual quantum correlations. https://doi.org/10.1103/physreva.87.010104

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