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Violation of a Bell-like Inequality in Neutron Optical Experiments: Quantum contextuality

Yuji Hasegawa·Rudolf Loidl·Gerald Badurek·Matthias Baron·Helmut Rauch
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Abstract

We report a single-neutron optical experiment to demonstrate the violation of a Bell-like inequality. Entanglement is achieved not between particles, but between the degrees of freedom, in this case, for a single-particle. The spin-{\small 1/2} property of neutrons are utilized. The total wave function of the neutron is described in a tensor product Hilbert space. A Bell-like inequality is derived not by a non-locality but by a contextuality. Joint measurements of the spinor and the path properties lead to the violation of a Bell-like inequality. Manipulation of the wavefunction in one Hilbert space influences the result of the measurement in the other Hilbert space. A discussion is given on the quantum contextuality and an entanglement-induced correlation in our experiment.

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Yuji Hasegawa, Rudolf Loidl, Gerald Badurek, Matthias Baron, Helmut Rauch. 2003-11-18. Violation of a Bell-like Inequality in Neutron Optical Experiments: Quantum contextuality. https://doi.org/10.1088/1464-4266/6/3/002

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