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Bounding the set of quantum correlations

Miguel Navascues·Stefano Pironio·Antonio Acin
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Abstract

We introduce a hierarchy of conditions necessarily satisfied by any distribution P(ab) representing the probabilities for two separate observers to obtain outcomes a and b when making local measurements on a shared quantum state. Each condition in this hierarchy is formulated as a semidefinite program. Our approach can be used to obtain upper-bounds on the quantum violation of an arbitrary Bell inequality. It yields, for instance, tight bounds for the violations of the Collins et al. inequalities.

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Miguel Navascues, Stefano Pironio, Antonio Acin. 2008-03-29. Bounding the set of quantum correlations. https://doi.org/10.1103/physrevlett.98.010401

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