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arXiv · 2303.02127

Bell inequalities with overlapping measurements

Moisés Bermejo Morán·Alejandro Pozas-Kerstjens·Felix Huber
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Abstract

Which nonlocal correlations can be obtained, when a party has access to more than one subsystem? While traditionally nonlocality deals with spacelike separated parties, this question becomes important with quantum technologies that connect devices by means of small shared systems. Here we study Bell inequalities where measurements of different parties can have overlap. This allows to accommodate problems in quantum information such as the existence of quantum error correction codes in the framework of non-locality. The scenarios considered show an interesting behaviour with respect to Hilbert space dimension, overlap, and symmetry.

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Moisés Bermejo Morán, Alejandro Pozas-Kerstjens, Felix Huber. 2023-03-03. Bell inequalities with overlapping measurements. https://doi.org/10.1103/physrevlett.131.080201

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