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Do all pure entangled states violate Bell's inequalities for correlation functions?

Marek Zukowski·Caslav Brukner·Wieslaw Laskowski·Marcin Wiesniak
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Abstract

Any pure entangled state of two particles violates a Bell inequality for two-particle correlation functions (Gisin's theorem). We show that there exist pure entangled N>2 qubit states that do not violate any Bell inequality for N particle correlation functions for experiments involving two dichotomic observables per local measuring station. We also find that Mermin-Ardehali-Belinskii-Klyshko inequalities may not always be optimal for refutation of local realistic description.

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Marek Zukowski, Caslav Brukner, Wieslaw Laskowski, Marcin Wiesniak. 2002-09-16. Do all pure entangled states violate Bell's inequalities for correlation functions?. https://doi.org/10.1103/physrevlett.88.210402

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