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Related papers: Contextuality versus Incompatibility

200 papers

Contextuality is a fundamental feature of quantum theory and is necessary for quantum computation and communication. Serious steps have therefore been taken towards a formal framework for contextuality as an operational resource. However,…

Quantum Physics · Physics 2018-04-26 Barbara Amaral , Adán Cabello , Marcelo Terra Cunha , Leandro Aolita

Contextuality and measurement incompatibility are two fundamental aspects of nonclassicality, and their manifestations in observed quantum correlations are often deeply interconnected. Recently, measurement incompatibility has been studied…

Quantum Physics · Physics 2026-04-07 Swati Kumari , Sumit Mukherjee , R. Prabhu

To make precise the sense in which nature fails to respect classical physics, one requires a formal notion of classicality. Ideally, such a notion should be defined operationally, so that it can be subjected to a direct experimental test,…

Quantum Physics · Physics 2016-06-21 Michael D. Mazurek , Matthew F. Pusey , Ravi Kunjwal , Kevin J. Resch , Robert W. Spekkens

Bell nonlocality and Kochen-Specker contextuality are two remarkable nonclassical features of quantum theory, related to strong correlations between outcomes of measurements performed on quantum systems. Both phenomena can be witnessed by…

Everyday experience supports the existence of physical properties independent of observation in strong contrast to the predictions of quantum theory. In particular, existence of physical properties that are independent of the measurement…

Quantum Physics · Physics 2016-03-09 Beatrix C. Hiesmayr , Jan-Å ke Larsson

We argue that for a \emph{single particle} Bell's inequality is a consequence of noncontextuality and is \emph{incompatible} with statistical predictions of quantum mechanics. Thus noncontextual models can be empirically falsified,…

Quantum Physics · Physics 2015-06-26 Sayandeb Basu , Somshubhro Bandyopadhyay , Guruprasad Kar , Dipankar Home

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

Contextuality is a fundamental manifestation of nonclassicality, indicating that for certain quantum correlations, sets of jointly measurable variables cannot be pre-assigned values independently of the measurement context. In this work, we…

Quantum Physics · Physics 2026-01-12 Chellasamy Jebarathinam , R. Srikanth

Contextual situations are those in which seemingly "the same" random variable changes its identity depending on the conditions under which it is recorded. Such a change of identity is observed whenever the assumption that the variable is…

Quantum Physics · Physics 2015-06-19 Ehtibar N. Dzhafarov , Janne V. Kujala

The question of whether quantum phenomena can be explained by classical models with hidden variables is the subject of a long lasting debate. In 1964, Bell showed that certain types of classical models cannot explain the quantum mechanical…

Quantum Physics · Physics 2009-07-21 G. Kirchmair , F. Zähringer , R. Gerritsma , M. Kleinmann , O. Gühne , A. Cabello , R. Blatt , C. F. Roos

Quantum theory has the intriguing feature that is inconsistent with noncontextual hidden variable models, for which the outcome of a measurement does not depend on which other compatible measurements are being performed concurrently. While…

Quantum Physics · Physics 2015-08-20 Hong-Yi Su , Jing-Ling Chen , Yeong-Cherng Liang

Contextuality is considered as an intrinsic signature of non-classicality, and a crucial resource for achieving unique advantages of quantum information processing. However, recently there have been debates on whether classical fields may…

Quantum Physics · Physics 2019-02-28 Aonan Zhang , Huichao Xu , Jie Xie , Han Zhang , Brian J. Smith , M. S. Kim , Lijian Zhang

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

In his article in Science, Nicolas Gisin claimed that quantum correlations emerge from outside space time. We explain that they are due to space time symmetries. This paper is a critical review of metaphysical conclusions found in many…

Quantum Physics · Physics 2024-02-29 Marian Kupczynski

An operational definition of contextuality is introduced which generalizes the standard notion in three ways: (1) it applies to arbitrary operational theories rather than just quantum theory, (2) it applies to arbitrary experimental…

Quantum Physics · Physics 2016-09-08 R. W. Spekkens

The existence of incompatible measurements is a fundamental phenomenon having no explanation in classical physics. Intuitively, one considers given measurements to be incompatible within a framework of a physical theory, if their…

Quantum Physics · Physics 2015-08-27 Teiko Heinosaari , Jukka Kiukas , Daniel Reitzner

In contrast with classical physics, in quantum physics some sets of measurements are incompatible in the sense that they can not be performed simultaneously. Among other applications, incompatibility allows for contextuality and Bell…

A violation of Bell-CHSH inequalities does not justify speculations about quantum non-locality, conspiracy and retro-causation. Such speculations are rooted in a belief that setting dependence of hidden variables in a probabilistic model,…

Quantum Physics · Physics 2023-02-06 Marian Kupczynski

Bohr's principle of complementarity, prohibiting simultaneous access to certain physical properties within a single experimental arrangement, is considered to be a defining feature of quantum mechanics. It is commonly viewed as inducing an…

Contextuality and nonlocality are distinct manifestations at the foundation of quantum mechanics, yet their coexistence within a single quantum state remains subtle. In a hybrid CHSH--KCBS scenario involving the entanglment of a qubit and a…

Quantum Physics · Physics 2026-04-07 Khai Nguyen , Duc M. Doan , Hung Q. Nguyen