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Violation of Bell's inequality: criterion for quantum communication complexity advantage

Caslav Brukner·Marek Zukowski·Jian-Wei Pan·Anton Zeilinger
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Abstract

We prove that for every Bell's inequality and for a broad class of protocols, there always exists a multi-party communication complexity problem, for which the protocol assisted by states which violate the inequality is more efficient than any classical protocol. Moreover, for that advantage Bell's inequality violation is a necessary and sufficient criterion. Thus, violation of Bell's inequalities has a significance beyond that of a non-optimal-witness of non-separability.

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Caslav Brukner, Marek Zukowski, Jian-Wei Pan, Anton Zeilinger. 2002-10-14. Violation of Bell's inequality: criterion for quantum communication complexity advantage. https://doi.org/10.1103/physrevlett.92.127901

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