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arXiv · 1709.09812

Generalized Hardy's Paradox

Shu-Han Jiang·Zhen-Peng Xu·Hong-Yi Su·Arun Kumar Pati·Jing-Ling Chen
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Abstract

Here we present the most general framework for $n$-particle Hardy's paradoxes, which include Hardy's original one and Cereceda's extension as special cases. Remarkably, for any $n\ge 3$ we demonstrate that there always exist generalized paradoxes (with the success probability as high as $1/2^{n-1}$) that are stronger than the previous ones in showing the conflict of quantum mechanics with local realism. An experimental proposal to observe the stronger paradox is also presented for the case of three qubits. Furthermore, from these paradoxes we can construct the most general Hardy's inequalities, which enable us to detect Bell's nonlocality for more quantum states.

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Shu-Han Jiang, Zhen-Peng Xu, Hong-Yi Su, Arun Kumar Pati, Jing-Ling Chen. 2017-09-28. Generalized Hardy's Paradox. https://doi.org/10.1103/physrevlett.120.050403

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