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arXiv · 2104.03988

Macroscopically nonlocal quantum correlations

Miguel Gallego·Borivoje Dakić
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Abstract

It is usually believed that coarse-graining of quantum correlations leads to classical correlations in the macroscopic limit. Such a principle, known as macroscopic locality, has been proved for correlations arising from independent and identically distributed (IID) entangled pairs. In this letter we consider the generic (non-IID) scenario. We find that the Hilbert space structure of quantum theory can be preserved in the macroscopic limit. This leads directly to a Bell violation for coarse-grained collective measurements, thus breaking the principle of macroscopic locality.

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Miguel Gallego, Borivoje Dakić. 2021-04-08. Macroscopically nonlocal quantum correlations. https://doi.org/10.1103/physrevlett.127.120401

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