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Bell's theorem without inequalities and without probabilities for two observers

Adan Cabello
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Abstract

A proof of Bell's theorem using two maximally entangled states of two qubits is presented. It exhibits a similar logical structure to Hardy's argument of ``nonlocality without inequalities''. However, it works for 100% of the runs of a certain experiment. Therefore, it can also be viewed as a Greenberger-Horne-Zeilinger-like proof involving only two spacelike separated regions.

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Adan Cabello. 2001-02-20. Bell's theorem without inequalities and without probabilities for two observers. https://doi.org/10.1103/physrevlett.86.1911

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