Quantummechanical realization of a PopescuRohrlich box
Abstract
We consider quantum ensembles which are determined by pre and postselection. Unlike the case of only preselected ensembles, we show that in this case the probabilities for measurement outcomes at intermediate times satisfy causality only rarely; such ensembles can in general be used to signal between causally disconnected regions. We show that under restrictive conditions, there are certain nontrivial bipartite ensembles which do satisfy causality. These ensembles give rise to a violation of the ClauserHorneShimonyHolt inequality, which exceeds the maximal quantum violation given by Tsirelson's bound B{sub CHSH}{<=}2{radical}(2) and obtains the PopescuRohrlich bound for the maximal violation, B{sub CHSH}{<=}4. This may be regarded as an a posteriori realization of supercorrelations, which have recently been termed PopescuRohrlich boxes.
 Authors:
 School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, TelAviv University, TelAviv 69978 (Israel)
 Publication Date:
 OSTI Identifier:
 20982061
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.022102; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CAUSALITY; CORRELATIONS; PROBABILITY; QUANTUM MECHANICS; VIOLATIONS
Citation Formats
Marcovitch, Samuel, Reznik, Benni, and Vaidman, Lev. Quantummechanical realization of a PopescuRohrlich box. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.022102.
Marcovitch, Samuel, Reznik, Benni, & Vaidman, Lev. Quantummechanical realization of a PopescuRohrlich box. United States. doi:10.1103/PHYSREVA.75.022102.
Marcovitch, Samuel, Reznik, Benni, and Vaidman, Lev. Thu .
"Quantummechanical realization of a PopescuRohrlich box". United States.
doi:10.1103/PHYSREVA.75.022102.
@article{osti_20982061,
title = {Quantummechanical realization of a PopescuRohrlich box},
author = {Marcovitch, Samuel and Reznik, Benni and Vaidman, Lev},
abstractNote = {We consider quantum ensembles which are determined by pre and postselection. Unlike the case of only preselected ensembles, we show that in this case the probabilities for measurement outcomes at intermediate times satisfy causality only rarely; such ensembles can in general be used to signal between causally disconnected regions. We show that under restrictive conditions, there are certain nontrivial bipartite ensembles which do satisfy causality. These ensembles give rise to a violation of the ClauserHorneShimonyHolt inequality, which exceeds the maximal quantum violation given by Tsirelson's bound B{sub CHSH}{<=}2{radical}(2) and obtains the PopescuRohrlich bound for the maximal violation, B{sub CHSH}{<=}4. This may be regarded as an a posteriori realization of supercorrelations, which have recently been termed PopescuRohrlich boxes.},
doi = {10.1103/PHYSREVA.75.022102},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}

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