A simple proof of the converse of Hardy's theorem

Jose L. Cereceda

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A simple proof of the converse of Hardy's theorem

Jose L. Cereceda

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Abstract

In this paper we provide a simple proof of the fact that for a system of two spin-1/2 particles, and for a choice of observables, there is a unique state which shows Hardy-type nonlocality. Moreover, an explicit expression for the probability that an ensemble of particle pairs prepared in such a state exhibits a Hardy-type nonlocality contradiction is given in terms of two independent parameters related to the observables involved. Incidentally, a wrong statement expressed in Mermin's proof of the converse [N.D. Mermin, Am. J. Phys. 62, 880 (1994)] is pointed out.

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Jose L. Cereceda. 1999-07-28. A simple proof of the converse of Hardy's theorem. https://arxiv.org/abs/quant-ph/9907094

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