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Causality and Cirel'son bounds

H. Buhrman·S. Massar
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Abstract

An EPR-Bell type experiment carried out on an entangled quantum system can produce correlations stronger than allowed by local realistic theories. However there are correlations that are no-signaling and are more non local than the quantum correlations. Here we show that any correlations more non local than those achievable in an EPR-Bell type experiment necessarily allow -in the context of the quantum formalism- both for signaling and for generation of entanglement. We use our approach to rederive Cirel'son bound for the CHSH expression, and we derive a new Cirel'son type bound for qutrits. We discuss in detail the interpretation of our approach.

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H. Buhrman, S. Massar. 2005-06-30. Causality and Cirel'son bounds. https://doi.org/10.1103/physreva.72.052103

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