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Related papers: Two proposals for testing quantum contextuality of…

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Quantum mechanics provides a statistical description about nature, and thus would be incomplete if its statistical predictions could not be accounted for some realistic models with hidden variables. There are, however, two powerful theorems…

Contextuality is a phenomenon at the heart of the quantum mechanical departure from classical behaviour, and has been recently identified as a resource in quantum computation. Experimental demonstration of contextuality is thus an important…

Quantum Physics · Physics 2019-03-26 Xiang Zhan , Eric G. Cavalcanti , Jian Li , Zhihao Bian , Yongsheng Zhang , Howard M. Wiseman , Peng Xue

We show that three unsharp binary qubit measurements are enough to violate a generalized noncontextuality inequality, the LSW inequality, in a state-dependent manner. For the case of trine spin axes we calculate the optimal quantum…

Quantum Physics · Physics 2014-05-15 Ravi Kunjwal , Sibasish Ghosh

When it isn't possible to tell two distinct experimental procedures apart purely from their input/output statistics, then it seems a plausible hypothesis that the two procedures must be physically identical. We call such a hypothesis…

Quantum Physics · Physics 2021-02-17 Ravi Kunjwal

The contextuality of quantum mechanics, i.e. the measurement outcome dependence upon previously made measurements, can be shown by the violation of inequalities based on measurements of well chosen observables. An important property of such…

Quantum Physics · Physics 2017-03-16 A. Laversanne-Finot , A. Ketterer , M. R. Barros , S. P. Walborn , T. Coudreau , A. Keller , P. Milman

We propose a scheme to test Bell's inequalities for an arbitrary number of measurement outcomes on entangled continuous variable states. The Bell correlation functions are expressible in terms of phase-space quasiprobability functions with…

Quantum Physics · Physics 2007-05-23 W. Son , C. Brukner , M. S. Kim

The CHSH inequality is an inequality used to test locality in quantum theory and is recognized as one of Bell's inequalities. In contrast, the KCBS inequality is employed to test noncontextuality in quantum theory. While certain quantum…

Quantum Physics · Physics 2025-07-10 Yuichiro Kitajima

A new theory-independent noncontextuality inequality is presented [Phys. Rev. Lett. 115, 110403 (2015)] based on Kochen-Specker (KS) set without imposing the assumption of determinism. By proposing novel noncontextuality inequalities, we…

Quantum Physics · Physics 2016-12-14 Zhen-Peng Xu , Debashis Saha , Hong-Yi Su , Marcin Pawlowski , Jing-Ling Chen

For a two-particle two-state system, sets of compatible propositions exist for which quantum mechanics and noncontextual hidden-variable theories make conflicting predictions for every individual system whatever its quantum state. This…

Quantum Physics · Physics 2009-01-23 Adan Cabello , Guillermo Garcia-Alcaine

By probabilistic means, the concept of contextuality is extended so that it can be used in non-ideal situations. An inequality is presented, which at least in principle enables a test to discard non-contextual hidden-variable models at low…

Quantum Physics · Physics 2022-03-16 Jan-Åke Larsson

The question of a hidden variable interpretation of quantum contextuality in the Mermin-Peres square is considered. The Kochen-Specker theorem implies that quantum mechanics may be interpreted as a contextual hidden variable theory. It is…

Quantum Physics · Physics 2021-05-04 Brian R. La Cour

Contextuality, the impossibility of assigning a single random variable to represent the outcomes of the same measurement procedure under different experimental conditions, is a central aspect of quantum mechanics. Thus defined, it appears…

Neurons and Cognition · Quantitative Biology 2016-02-17 J. Acacio de Barros , Gary Oas

Quantum mechanics provides a statistical description about nature, and thus would be incomplete if its statistical predictions could not be accounted for by some realistic models with hidden variables. There are, however, two powerful…

Quantum Physics · Physics 2012-10-04 Xi Kong , Mingjun Shi , Fazhan Shi , Pengfei Wang , Pu Huang , Qi Zhang , Chenyong Ju , Changkui Duan , Sixia Yu , Jiangfeng Du

The Kochen-Specker (KS) theorem is a fundamental result in quantum foundations that has spawned massive interest since its inception. We present state-independent non-contextuality inequalities with large violations, in particular, we…

Quantum Physics · Physics 2022-12-22 Ravishankar Ramanathan , Yuan Liu , Paweł Horodecki

KS-contextuality is a crucial feature of quantum theory. Previous research demonstrated the vanishing of $N$-cycle KS-contextuality in setups where multiple independent observers measure sequentially on the same system, which we call Public…

Quantum Physics · Physics 2023-12-05 Arthur C. R. Dutra , Roberto D. Baldijão , Marcelo Terra Cunha

The conflict between classical and quantum physics can be identified through a series of yes-no tests on quantum systems, without it being necessary that these systems be in special quantum states. Kochen-Specker (KS) sets of yes-no tests…

The testability of the Kochen-Specker theorem is a subject of ongoing controversy. A central issue is that experimental implementations relying on sequential measurements cannot achieve perfect compatibility between the measurements and…

Quantum Physics · Physics 2013-05-15 Jochen Szangolies , Matthias Kleinmann , Otfried Gühne

Kochen-Specker theorems assure the breakdown of certain types of non-contextual hidden variable theories through the non-existence of global, holistic frame functions; alas they do not allow us to identify where this breakdown occurs, nor…

Quantum Physics · Physics 2014-03-11 Alastair A. Abbott , Cristian S. Calude , Karl Svozil

We study an asymmetric form of two-mode entangled coherent state (ECS), where the two local amplitudes have different values, for testing the Bell-Clauser-Horne-Shimony-Holt (Bell-CHSH) inequality. We find that the asymmetric ECSs have…

Quantum Physics · Physics 2015-05-20 Chae-Yeun Park , Hyunseok Jeong

A continuous-variable Bell inequality, valid for an arbitrary number of observers measuring observables with an arbitrary number of outcomes, was recently introduced in [Cavalcanti \emph{et al.}, Phys. Rev. Lett. {\bf 99}, 210405 (2007)].…

Quantum Physics · Physics 2008-07-25 Alejo Salles , Daniel Cavalcanti , Antonio Acín