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Bell's inequalities for states with positive partial transpose

Reinhard F. Werner·Michael M. Wolf
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Abstract

We study violations of n particle Bell inequalities (as developed by Mermin and Klyshko) under the assumption that suitable partial transposes of the density operator are positive. If all transposes with respect to a partition of the system into p subsystems are positive, the best upper bound on the violation is 2^((n-p)/2). In particular, if the partial transposes with respect to all subsystems are positive, the inequalities are satisfied. This is supporting evidence for a recent conjecture by Peres that positivity of partial transposes could be equivalent to existence of local classical models.

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Reinhard F. Werner, Michael M. Wolf. 1999-10-14. Bell's inequalities for states with positive partial transpose. https://doi.org/10.1103/physreva.61.062102

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