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Single-particle nonlocality and entanglement with the vacuum

G. Bjork·P. Jonsson·L. L. Sanchez-Soto
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Abstract

We propose a single-particle experiment that is equivalent to the conventional two-particle experiment used to demonstrate a violation of Bell's inequalities. Hence, we argue that quantum mechanical nonlocality can be demonstrated by single-particle states. The validity of such a claim has been discussed in the literature, but without reaching a clear consensus. We show that the disagreement can be traced to what part of the total state of the experiment one assigns to the (macroscopic) measurement apparatus. However, with a conventional and legitimate interpretation of the measurement process one is led to the conclusion that even a single particle can show nonlocal properties.

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G. Bjork, P. Jonsson, L. L. Sanchez-Soto. 2001-03-14. Single-particle nonlocality and entanglement with the vacuum. https://doi.org/10.1103/physreva.64.042106

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