English
Related papers

Related papers: Converting contextuality into nonlocality

200 papers

Quantum mechanics exhibits a very peculiar form of contextuality. Identifying and connecting the simplest scenarios in which more general theories can or cannot be more contextual than quantum mechanics is a fundamental step in the quest…

Quantum Physics · Physics 2013-02-18 Adan Cabello

Quantum nonlocality, one of the most important features of quantum mechanics, is normally connected in experiments with the violation of Bell-Clauser-Horne (Bell-CH) inequalities. We propose effective methods for the rearrangement and…

Quantum Physics · Physics 2021-06-08 Chen Qian , Yang-Guang Yang , Cong-Feng Qiao , Qun Wang

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

Characterising unknown quantum states and measurements is a fundamental problem in quantum information processing. In this Letter, we provide a novel scheme to self-test local quantum systems using non-contextuality inequalities. Our work…

Bell non-locality is a fundamental feature of quantum mechanics whereby measurements performed on "spatially separated" quantum systems can exhibit correlations that cannot be understood as revealing predetermined values. This is a special…

Quantum Physics · Physics 2024-11-05 Atul Singh Arora , Kishor Bharti , Alexandru Cojocaru , Andrea Coladangelo

We propose a method to generate analytical quantum Bell inequalities based on the principle of Macroscopic Locality. By imposing locality over binary processings of virtual macroscopic intensities, we establish a correspondence between Bell…

Quantum Physics · Physics 2011-02-17 Tzyh Haur Yang , Miguel Navascués , Lana Sheridan , Valerio Scarani

Contextuality is a natural generalization of nonlocality which does not need composite systems or spacelike separation and offers a wider spectrum of interesting phenomena. Most notably, in quantum mechanics there exist scenarios where the…

Quantum Physics · Physics 2022-03-16 Matthias Kleinmann , Costantino Budroni , Jan-Åke Larsson , Otfried Gühne , Adan Cabello

The structure of Bell-type inequalities detecting genuine multipartite non-locality, and hence detecting genuine multipartite entanglement, is investigated. We first present a simple and intuitive approach to Svetlichny's original…

Quantum Physics · Physics 2014-10-20 Jean-Daniel Bancal , Nicolas Brunner , Nicolas Gisin , Yeong-Cherng Liang

What violations of Bell inequalities teach us is that the world is quantum mechanical, i.e., nonclassical. Assertions that they imply the world is nonlocal arise from ignoring differences between quantum and classical physics.

Quantum Physics · Physics 2013-04-17 Robert B. Griffiths

Quantum theory violates Bell's inequality, but not to the maximum extent that is logically possible. We derive inequalities (generalizations of Cirel'son's inequality) that quantify the upper bound of the violation, both for the standard…

Quantum Physics · Physics 2009-11-07 Dennis Dieks

We present generic Bell inequalities for multipartite multi-dimensional systems. The inequalities that any local realistic theories must obey are violated by quantum mechanics for even-dimensional multipartite systems. A large set of…

Quantum Physics · Physics 2009-11-11 W. Son , Jinhyoung Lee , M. S. Kim

We consider relations between communication complexity problems and detecting correlations (violating local realism) with no local hidden variable model. We show first universal equivalence between characteristics of protocols used in that…

Quantum Physics · Physics 2015-10-16 L. Czekaj , A. Grudka , M. Horodecki , P. Horodecki , M. Markiewicz

Based on the new general framework for the probabilistic description of experiments, introduced in quant-ph/0305126, quant-ph/0312199, we analyze in mathematical terms the link between the validity of Bell-type inequalities under joint…

Quantum Physics · Physics 2007-05-23 Elena R. Loubenets

Contextuality is a distinctive feature of quantum theory and a fundamental resource for quantum computation. However, existing examples of contextuality in high-dimensional systems lack the necessary robustness required in experiments. Here…

We present the necessary and sufficient condition for the violation of a new series of multipartite Bell's inequalities with many measurement settings.

Quantum Physics · Physics 2007-05-23 Wieslaw Laskowski , Tomasz Paterek , Marek Zukowski

We present and experimentally demonstrate a novel non-classical phenomenon, bi-contextuality, observed in quantum systems prepared by two independent sources. This discovery plays a key role in the developing framework of network…

We show that the maximum quantum violation of the Klyachko-Can-Binicioglu-Shumovsky (KCBS) inequality is exactly the maximum value satisfying the following principle: The sum of probabilities of pairwise exclusive events cannot exceed 1. We…

Quantum Physics · Physics 2013-02-18 Adan Cabello

We present a tomographic approach to the study of quantum nonlocality in multipartite systems. Bell inequalities for tomograms belonging to a generic tomographic scheme are derived by exploiting tools from convex geometry. Then, possible…

Quantum Physics · Physics 2015-06-23 Evgeny V. Shchukin , Stefano Mancini

Finding quantitative aspects of quantum phenomena which cannot be explained by any classical model has foundational importance for understanding the boundary between classical and quantum theory. It also has practical significance for…

Quantum Physics · Physics 2018-02-06 David Schmid , Robert W. Spekkens

Contextuality means non-existence of a joint distribution for random variables recorded under mutually incompatible conditions, subject to certain constraints imposed on how the identity of these variables may change across these…

Quantum Physics · Physics 2015-02-06 Ehtibar N. Dzhafarov , Janne V. Kujala