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arXiv · 0904.4576

Experimental test of quantum contextuality in neutron interferometry

H. Bartosik·J. Klepp·C. Schmitzer·S. Sponar·A. Cabello·H. Rauch·Y. Hasegawa
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Abstract

We performed an experimental test of the Kochen-Specker theorem based on an inequality derived from the Peres-Mermin proof, using spin-path (momentum) entanglement in a single neutron system. Following the strategy proposed by Cabello et al. [Phys. Rev. Lett. 100, 130404 (2008)], a Bell-like state was generated and three expectation values were determined. The observed violation 2.291 +/- 0.008 > 1 clearly shows that quantum mechanical predictions cannot be reproduced by noncontextual hidden variables theories.

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H. Bartosik, J. Klepp, C. Schmitzer, S. Sponar, A. Cabello, H. Rauch, Y. Hasegawa. 2009-07-23. Experimental test of quantum contextuality in neutron interferometry. https://doi.org/10.1103/physrevlett.103.040403

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