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Entropy inequalities and Bell inequalities for two-qubit systems

Emilio Santos
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Abstract

Sufficient conditions for (the non-violation of) the Bell-CHSH inequalities in a mixed state of a two-qubit system are: 1) The linear entropy of the state is not smaller than 0.5, 2) The sum of the conditional linear entropies is non-negative, 3) The von Neumann entropy is not smaller than 0.833, 4) The sum of the conditional von Neumann entropies is not smaller than 0.280.

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Emilio Santos. 2004-10-07. Entropy inequalities and Bell inequalities for two-qubit systems. https://doi.org/10.1103/physreva.69.022305

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