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Related papers: Contextuality in phase space

200 papers

Contextuality is a fundamental property of quantum theory and a critical resource for quantum computation. Here, we experimentally observe the arguably cleanest form of contextuality in quantum theory [A. Cabello \emph{et al.}, Phys. Rev.…

Quantum Physics · Physics 2014-12-24 Breno Marques , Johan Ahrens , Mohamed Nawareg , Adan Cabello , Mohamed Bourennane

I will argue that the Peres-Mermin square does not necessarily rule out a value-definite (deterministic) noncontextual hidden variable model if the operators are not given a physical interpretation satisfying the following two requirements:…

Quantum Physics · Physics 2020-11-13 Gábor Hofer-Szabó

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 phase space $S\times Z$ for a particle on a circle is considered. Displacement operators in this phase space are introduced and their properties are studied. Wigner and Weyl functions in this context are also considered and their…

Quantum Physics · Physics 2009-11-11 S. Zhang , A. Vourdas

We discuss quantum non-locality and contextuality using the notion of transition sets. This approach provides a way to obtain a direct logical contradiction with locality/non-contextuality in the EPRB gedanken experiment as well as a clear…

Quantum Physics · Physics 2007-11-19 Hans Westman

We consider the phenomenon of quantum mechanical contextuality, and specifically parity-based proofs thereof. Mermin's square and star are representative examples. Part of the information invoked in such contextuality proofs is the…

Quantum Physics · Physics 2020-01-08 Cihan Okay , Robert Raussendorf

We present a new and feasible test proving quantum contextuality in four-dimensional Hiltbert space. In our scheme, a contradiction between quantum mechanics and noncontextual hidden variables is revealed through the measurement statistics…

Quantum Physics · Physics 2008-06-27 Yoshihiro Nambu

We provide a cohomological framework for contextuality of quantum mechanics that is suited to describing contextuality as a resource in measurement-based quantum computation. This framework applies to the parity proofs first discussed by…

Quantum Physics · Physics 2017-10-18 Cihan Okay , Sam Roberts , Stephen D. Bartlett , Robert Raussendorf

Quantum contextuality takes an important place amongst the concepts of quantum computing that bring an advantage over its classical counterpart. For a large class of contextuality proofs, aka. observable-based proofs of the Kochen-Specker…

We introduce a new framework for contextuality based on simplicial sets, combinatorial models of topological spaces that play a prominent role in modern homotopy theory. Our approach extends measurement scenarios to consist of spaces…

Quantum Physics · Physics 2023-05-24 Cihan Okay , Aziz Kharoof , Selman Ipek

We consider any noncontextuality inequality, and the state preparation scheme which consists in performing any von Neumann measurement on any initial state. For an inequality which is not always satisfied, and Hilbert space dimensions…

Quantum Physics · Physics 2016-08-24 S. Camalet

An important approach for efficient inference in probabilistic graphical models exploits symmetries among objects in the domain. Symmetric variables (states) are collapsed into meta-variables (meta-states) and inference algorithms are run…

Artificial Intelligence · Computer Science 2016-07-01 Ankit Anand , Aditya Grover , Mausam , Parag Singla

A PhD student is locked inside a box, imitating a quantum system by mimicking the measurement statistics of any viable observable nominated by external observers. Inside a second box lies a genuine quantum system. Either box can be used to…

Quantum Physics · Physics 2015-06-19 Jayne Thompson , Mile Gu , Pawel Kurzynski , Su-Yong Lee , Dagomir Kaszlikowski

We construct phase space localizing operators in all dimensions. These are frequency localized variants of the conditional expectation operator related to a dyadic stopping time. Our construction is an improvement over the so-called phase…

Classical Analysis and ODEs · Mathematics 2024-02-20 Marco Fraccaroli , Olli Saari , Christoph Thiele

We introduce a new notion, that of a contextuality profile of a system of random variables. Rather than characterizing a system's contextuality by a single number, its overall degree of contextuality, we show how it can be characterized by…

Quantum Physics · Physics 2026-05-04 Ehtibar N. Dzhafarov , Victor H. Cervantes

The problem of identifying measurement scenarios capable of revealing state-independent contextuality in a given Hilbert space dimension is considered. We begin by showing that for any given dimension $d$ and any measurement scenario…

Quantum Physics · Physics 2014-02-05 Ravishankar Ramanathan , Pawel Horodecki

Contextuality is a defining feature that separates the quantum from the classical descriptions of physical systems. Within the marginal-scenario framework, noncontextual models are characterized by the existence of a single joint…

Quantum Physics · Physics 2026-04-08 Andrea Navoni , Marco G. Genoni , Andrea Smirne

Recent years have seen new general notions of contextuality emerge. Most of these employ context-independent symbols to represent random variables in different contexts. As an example, the operational theory of Spekkens [1] treats an…

Quantum Physics · Physics 2020-11-16 Mojtaba Aliakbarzadeh , Kirsty Kitto

The Contextuality-by-Default approach to determining and measuring the (non)contextuality of a system of random variables requires that every random variable in the system be represented by an equivalent set of dichotomous random variables.…

Quantum Physics · Physics 2022-01-05 Janne V. Kujala , Ehtibar N. Dzhafarov

In the Contextuality-by-Default theory random variables representing measurement outcomes are labeled contextually, i.e., not only by what they measure but also under what conditions (in what contexts) the measurements are made, including…

Quantum Physics · Physics 2018-12-11 Ehtibar N. Dzhafarov