Reassessment of the nonlocality of correlation boxes
Abstract
Correlation boxes are hypothetical systems usually designed to produce the maximal algebraic violation of a Bell inequality, beyond the quantum bound and without superluminal signalling. The fact that these systems show stronger correlations than those presented by maximally entangled quantum states, as the spin singlet, has been regarded as a demonstration that the former are more nonlocal than the latter. By applying an alternative, consistent measure of nonlocality to a family of correlation boxes, we show that this conclusion is not necessarily true. Complementarily, we define a class of systems displaying subquantum correlations which, nevertheless, are more nonlocal than the singlet state, showing that the extent of the numeric violation of an inequality may have little to do with the degree of nonlocality, especially in the case of correlation boxes.
 Authors:
 Publication Date:
 OSTI Identifier:
 22617456
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Annals of Physics; Journal Volume: 376; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BELL THEOREM; QUANTUM ENTANGLEMENT; QUANTUM STATES
Citation Formats
Costa, A.P., and Parisio, Fernando, Email: parisio@df.ufpe.br. Reassessment of the nonlocality of correlation boxes. United States: N. p., 2017.
Web. doi:10.1016/J.AOP.2016.12.023.
Costa, A.P., & Parisio, Fernando, Email: parisio@df.ufpe.br. Reassessment of the nonlocality of correlation boxes. United States. doi:10.1016/J.AOP.2016.12.023.
Costa, A.P., and Parisio, Fernando, Email: parisio@df.ufpe.br. Sun .
"Reassessment of the nonlocality of correlation boxes". United States.
doi:10.1016/J.AOP.2016.12.023.
@article{osti_22617456,
title = {Reassessment of the nonlocality of correlation boxes},
author = {Costa, A.P. and Parisio, Fernando, Email: parisio@df.ufpe.br},
abstractNote = {Correlation boxes are hypothetical systems usually designed to produce the maximal algebraic violation of a Bell inequality, beyond the quantum bound and without superluminal signalling. The fact that these systems show stronger correlations than those presented by maximally entangled quantum states, as the spin singlet, has been regarded as a demonstration that the former are more nonlocal than the latter. By applying an alternative, consistent measure of nonlocality to a family of correlation boxes, we show that this conclusion is not necessarily true. Complementarily, we define a class of systems displaying subquantum correlations which, nevertheless, are more nonlocal than the singlet state, showing that the extent of the numeric violation of an inequality may have little to do with the degree of nonlocality, especially in the case of correlation boxes.},
doi = {10.1016/J.AOP.2016.12.023},
journal = {Annals of Physics},
number = ,
volume = 376,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2017},
month = {Sun Jan 15 00:00:00 EST 2017}
}

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