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Related papers: Contextuality and Random Variables

200 papers

Contextuality provides a unifying paradigm for nonclassical aspects of quantum probabilities and resources of quantum information. Unfortunately, most forms of quantum contextuality remain experimentally unexplored due to the difficulty of…

Quantum Physics · Physics 2016-03-02 Adán Cabello

The quantum fluctuations of a physical property can be observed in the measurement statistics of any measurement that is at least partially sensitive to that physical property. Quantum theory indicates that the effective distribution of…

Quantum Physics · Physics 2020-12-25 Holger F. Hofmann

The amount of contextuality is quantified in terms of the probability of the necessary violations of noncontextual assignments to counterfactual elements of physical reality.

Quantum Physics · Physics 2012-03-21 Karl Svozil

Contextuality is a key characteristic that separates quantum from classical phenomena and an important tool in understanding the potential advantage of quantum computation. However, when assessing the quantum resources available for quantum…

Quantum Physics · Physics 2026-03-04 Maiyuren Srikumar , Stephen D. Bartlett , Angela Karanjai

Contextuality, a key resource for quantum advantage, describes systems in which the outcome of a measurement is not independent of other compatible measurements, in contrast to classical hidden-variable descriptions. We investigate the…

Quantum Physics · Physics 2025-12-08 Caroline Lima , María Rosa Preciado-Rivas , Sanchit Srivastava

Contextuality is a non-classical behaviour that can be exhibited by quantum systems. It is increasingly studied for its relationship to quantum-over-classical advantages in informatic tasks. To date, it has largely been studied in…

Quantum Physics · Physics 2022-04-20 Rui Soares Barbosa , Tom Douce , Pierre-Emmanuel Emeriau , Elham Kashefi , Shane Mansfield

We consider the contextual fraction as a quantitative measure of contextuality of empirical models, i.e. tables of probabilities of measurement outcomes in an experimental scenario. It provides a general way to compare the degree of…

Quantum Physics · Physics 2017-08-09 Samson Abramsky , Rui Soares Barbosa , Shane Mansfield

Quantum theory features several phenomena which can be considered as resources for information processing tasks. Some of these effects, such as entanglement, arise in a nonlocal scenario, where a quantum state is distributed between…

Quantum Physics · Physics 2024-07-22 Martin Plávala , Otfried Gühne

We present a formal theory of contextuality for a set of random variables grouped into different subsets (contexts) corresponding to different, mutually incompatible conditions. Within each context the random variables are jointly…

Quantum Physics · Physics 2015-09-01 Ehtibar N. Dzhafarov , Janne V. Kujala , Jan-Åke Larsson

Contextuality is central to both the foundations of quantum theory and to the novel information processing tasks. Although it was recognized before Bell's nonlocality, despite some recent proposals, it still faces a fundamental problem: how…

Quantum Physics · Physics 2014-04-02 A. Grudka , K. Horodecki , M. Horodecki , P. Horodecki , R. Horodecki , P. Joshi , W. Kłobus , A. Wójcik

Cyclic systems of dichotomous random variables have played a prominent role in contextuality research, describing such experimental paradigms as the Klyachko-Can-Binicoglu-Shumovky, Einstein-Podolsky-Rosen-Bell, and Leggett-Garg ones in…

Quantum Physics · Physics 2021-05-19 Ehtibar N. Dzhafarov , Janne V. Kujala , Víctor H. Cervantes

We describe a mathematical language for determining all possible patterns of contextuality in the dependence of stochastic outputs of a system on its deterministic inputs. The central notion is that of all possible couplings for…

Mathematical Physics · Physics 2015-01-27 Ehtibar N. Dzhafarov , Janne V. Kujala

Randomness is a crucial resource for a broad range of important applications, such as Monte Carlo simulation and computation, generative artificial intelligence and cryptography. But what is randomness? A widely accepted definition has…

Quantum Physics · Physics 2024-10-01 Mario Stipčević

The average result of a weak measurement of some observable $A$ can, under post-selection of the measured quantum system, exceed the largest eigenvalue of $A$. The nature of weak measurements, as well as the presence of post-selection and…

Quantum Physics · Physics 2014-11-13 Matthew F. Pusey

Most behavioral and social experiments aimed at revealing contextuality are confined to cyclic systems with binary outcomes. In quantum physics, this broad class of systems includes as special cases Klyachko-Can-Binicioglu-Shumovsky-type,…

Neurons and Cognition · Quantitative Biology 2016-02-12 Ehtibar Dzhafarov , Ru Zhang , Janne Kujala

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

We introduce a contextual quantum system comprising mutually complementary observables organized into two or more collections of pseudocontexts with the same probability sums of outcomes. These pseudocontexts constitute non-orthogonal bases…

Quantum Physics · Physics 2024-04-05 Mirko Navara , Karl Svozil

Contextuality is the failure of "local" probabilistic models to become global ones. In this paper we introduce the notions of \emph{measurable fibre bundles}, \emph{probability fibre bundles}, and \emph{sample fibre bundle} which capture…

Probability · Mathematics 2021-03-10 Marcelo Terra Cunha

Results of measurements give legitimacy to a physical theory. What if acquiring these results in the first place necessitates what the same theory considers to be an interaction? In this note, we assume that theories account for…

Quantum Physics · Physics 2019-05-01 Arne Hansen , Stefan Wolf

Contextuality has long been associated with topological properties. In this work, such a relationship is elevated to identification in the broader framework of generalized contextuality. We employ the usual identification of states,…

Quantum Physics · Physics 2024-07-04 Sidiney B. Montanhano