arXiv:quant-ph/0110095 · Physical Review Letters

Do All Pure Entangled States Violate Bell’s Inequalities for Correlation Functions?

Marek Żukowski, Časlav Brukner, Wiesław Laskowski, Marcin Wieśniak

Published May 9, 2002• 111 citations

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.

DOI: 10.1103/physrevlett.88.210402

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