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Comment on "Quantum nonlocality for a three-particle nonmaximally entangled state without inequalities"

Jose L. Cereceda
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Abstract

In a recent Brief Report, Zheng [S-B. Zheng, PRA 66, 014103 (2002)] has given a proof of nonlocality without using inequalities for three spin-1/2 particles in the nonmaximally entangled state |psi> = cosθ|+++> + i sinθ|-->. Here we show that Zheng's proof is not correct. Indeed it is the case that, for the experiment considered by Zheng, the only state that admits a nonlocality proof without inequalities is the maximally entangled state.

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Jose L. Cereceda. 2003-12-05. Comment on "Quantum nonlocality for a three-particle nonmaximally entangled state without inequalities". https://arxiv.org/abs/quant-ph/0312046

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