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Related papers: Bell Inequality Violation and Relativity of Pre- a…

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Correlations that cannot be reproduced with local variables certify the generation of private randomness. Usually, the violation of a Bell inequality is used to quantify the amount of randomness produced. Here, we show how private…

Quantum Physics · Physics 2014-04-16 Jean-Daniel Bancal , Lana Sheridan , Valerio Scarani

Bipartite temporal Bell inequalities are similar to the usual Bell inequalities except that, instead of changing the direction of the polariser at each measurement, one changes the time at which the measurement is being performed. By doing…

Quantum Physics · Physics 2020-11-18 Kenta Ando , Vincent Vennin

D\"{u}r [Phys. Rev. Lett. {\bf 87}, 230402 (2001)] constructed $N$-qubit bound entangled states which violate a Bell inequality for $N\ge 8$, and his result was recently improved by showing that there exists an $N$-qubit bound entangled…

Quantum Physics · Physics 2013-05-29 Dong Pyo Chi , Kabgyun Jeong , Taewan Kim , Kyungjin Lee , Soojoon Lee

Bell's theorem states that some predictions of quantum mechanics cannot be reproduced by a local-realist theory. That conflict is expressed by Bell's inequality, which is usually derived under the assumption that there are no statistical…

A simple minimalist argument is given for why some correlations between quantum systems boggle our classical intuition. The argument relies on two elementary physical assumptions, and recovers the standard experimentally-testable Bell…

Quantum Physics · Physics 2024-08-29 Michael J. W. Hall

The logical foundations of Bell's inequality are reexamined. We argue that the form of the reality condition that underpins Bell's inequality comes from the requirement of solving the quantum measurement problem. Hence any violation of…

Quantum Physics · Physics 2008-02-19 John V. Corbett , Dipankar Home

Bell's theorem is a no-go theorem stating that quantum mechanics cannot be reproduced by a physical theory based on realism, freedom to choose experimental settings and two locality conditions: setting (SI) and outcome (OI) independence. We…

Quantum Physics · Physics 2015-05-13 M. Pawlowski , J. Kofler , T. Paterek , M. Seevinck , C. Brukner

The propagation of macroscopic entangled states over large distances in the presence of loss is of fundamental interest and may have practical applications as well. Here we describe two different techniques in which state discrimination can…

Quantum Physics · Physics 2014-04-23 B. T. Kirby , J. D. Franson

Quantum mechanics allows for coherent control over the order in which different processes take place on a target system, giving rise to a new feature known as indefinite causal order. Indefinite causal order provides a resource for quantum…

In a recent paper published in PNAS authors prove that locality and free choice are equivalent resources which need to be relaxed in order to fully reproduce some statistics in Bell experiments (while always maintaining realism). We explain…

Quantum Physics · Physics 2021-06-01 Marian Kupczynski

We describe a new Bell test for two-particle entangled systems that engages an unbounded continuous variable. The continuous variable state is allowed to be arbitrary and inaccessible to direct measurements. A systematic method is…

Quantum Physics · Physics 2014-01-20 X. -F. Qian , C. J. Broadbent , J. H. Eberly

Many Bell test results violate Bell's inequality. The premise of Bell's inequality is local determinism. We propose that, it can't be proved that something's mechanism isn't deterministic; if loopholes are not the reason of violation of…

Quantum Physics · Physics 2013-07-30 Shoujiang Wang , Xiulan Wang

For a class of mixed two -qubit states we show that it is not possible to discriminate between states violating or non - violating Bell - CHSH inequalities, knowing only their entanglement and mixedness. For a large set of possible values…

Quantum Physics · Physics 2009-11-10 L. Derkacz , L. Jakobczyk

We consider quantum systems composed of $N$ qubits, and the family of all Bell's correlation inequalities for two two-valued measurements per site. We show that if a $N$-qubit state $\rho$ violates any of these inequalities, then it is at…

Quantum Physics · Physics 2009-11-07 A. Acin , V. Scarani , M. M. Wolf

It is argued that the concept of ``physical quantities possessed by the system'' is both redundant and inappropriate. We have examined two versions of the concept of ``possessed values'': one identical with the observed values and the other…

Quantum Physics · Physics 2007-05-23 Zae-young Ghim , Hwe Ik Zhang

We analyse the recent claim that a violation of a Bell's inequality has been observed in the $B$--meson system [A. Go, {\em Journal of Modern Optics} {\bf 51} (2004) 991]. The results of this experiment are a convincing proof of quantum…

Quantum Physics · Physics 2009-11-10 A. Bramon , R. Escribano , G. Garbarino

Violations of Bell inequalities are better preserved by turbulent atmospheric channels than by comparable optical fibers in the scenario of copropagating entangled photons [A.A. Semenov and W. Vogel, Phys. Rev. A 81, 023835 (2010);…

Quantum Physics · Physics 2016-11-03 M. O. Gumberidze , A. A. Semenov , D. Vasylyev , W. Vogel

For a system composed of two particles Bell's theorem asserts that averages of physical quantities determined from local variables must conform to a family of inequalities. In this work we show that a classical model containing a local…

Quantum Physics · Physics 2008-06-22 A. Matzkin

By taking into account that all real measurements are performed successively, during time, it is concluded that the violation of the Bell's inequalities in the Nature does not refute (even in an ideally perfect experiment) the theories…

Quantum Physics · Physics 2014-02-26 Alejandro A. Hnilo

Violation of Bell inequalities is an essential requirement for many quantum information and communication protocols. In high-dimensional systems, Bell inequality tests face the challenge of implementing genuinely multi-outcome measurements,…