Qualitative equivalence between incompatibility and Bell nonlocality

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Yadavalli, Shiv Akshar, Andrejic, Nikola, Kunjwal, Ravi
Format: Preprint
Publié: 2020
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866910705674878976
author Yadavalli, Shiv Akshar
Andrejic, Nikola
Kunjwal, Ravi
author_facet Yadavalli, Shiv Akshar
Andrejic, Nikola
Kunjwal, Ravi
contents Measurements in quantum theory can fail to be jointly measurable. Like entanglement, this incompatibility of measurements is necessary but not sufficient for violating Bell inequalities. The (in)compatibility relations among a set of measurements can be represented by a joint measurability structure, i.e., a hypergraph whose vertices denote measurements and hyperedges denote all and only compatible sets of measurements. Since incompatibility is necessary for a Bell violation, the joint measurability structure on each wing of a Bell experiment must necessarily be non-trivial, i.e., it must admit a subset of incompatible vertices. Here we show that for any non-trivial joint measurability structure with a finite set of vertices, there exists a quantum realization with a set of measurements that enables a Bell violation, i.e., given that Alice has access to this incompatible set of measurements, there exists a set of measurements for Bob and an entangled state shared between them such that they can jointly violate a Bell inequality. Hence, a non-trivial joint measurability structure is not only necessary for a Bell violation, but also sufficient.
format Preprint
id arxiv_https___arxiv_org_abs_2008_10100
institution arXiv
publishDate 2020
record_format arxiv
spellingShingle Qualitative equivalence between incompatibility and Bell nonlocality
Yadavalli, Shiv Akshar
Andrejic, Nikola
Kunjwal, Ravi
Quantum Physics
Measurements in quantum theory can fail to be jointly measurable. Like entanglement, this incompatibility of measurements is necessary but not sufficient for violating Bell inequalities. The (in)compatibility relations among a set of measurements can be represented by a joint measurability structure, i.e., a hypergraph whose vertices denote measurements and hyperedges denote all and only compatible sets of measurements. Since incompatibility is necessary for a Bell violation, the joint measurability structure on each wing of a Bell experiment must necessarily be non-trivial, i.e., it must admit a subset of incompatible vertices. Here we show that for any non-trivial joint measurability structure with a finite set of vertices, there exists a quantum realization with a set of measurements that enables a Bell violation, i.e., given that Alice has access to this incompatible set of measurements, there exists a set of measurements for Bob and an entangled state shared between them such that they can jointly violate a Bell inequality. Hence, a non-trivial joint measurability structure is not only necessary for a Bell violation, but also sufficient.
title Qualitative equivalence between incompatibility and Bell nonlocality
topic Quantum Physics
url https://arxiv.org/abs/2008.10100