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Related papers: Bell Inequalities in Phase Space and their Violati…

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A systematic approach is presented to construct non-homogeneous two- and three-qubit Bell-type inequalities. When projector-like terms are subtracted from homogeneous two-qubit CHSH polynomial, non-homogeneous inequalities are attained and…

Quantum Physics · Physics 2009-01-22 Mingjun Shi , Changliang Ren , Jiangfeng Du

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 study a phenomenon occuring in various areas of quantum physics, in which an observable density (such as an energy density) which is classically pointwise nonnegative may assume arbitrarily negative expectation values after quantisation,…

Mathematical Physics · Physics 2007-05-23 Simon P. Eveson , Christopher J. Fewster , Rainer Verch

Entanglement and violation of Bell inequalities are aspects of quantum nonlocality that have been often confused in the past. It is now known that this equivalence is only true for pure states. Even though almost all the studies of quantum…

Quantum Physics · Physics 2012-06-01 L. Justino , Thiago R. de Oliveira

We derive a Bell inequality based on a generalized quasiprobability function which is parameterized by one non-positive real value. Two types of known Bell inequalities formulated in terms of the Wigner and Q functions are included as…

Quantum Physics · Physics 2009-08-06 Seung-Woo Lee , Hyunseok Jeong , Dieter Jaksch

For a system composed of two particles Bell's theorem asserts that averages of physical quantities determined from local variables must conform to a family of inequalities. In this work we show that a classical model containing a local…

Quantum Physics · Physics 2008-06-22 A. Matzkin

Bell non-locality is a term that applies to specific modifications and interpretations of quantum mechanics. Yet, Bell's original 1964 theorem is often used to assert that unmodified quantum mechanics itself is non-local and that local…

Quantum Physics · Physics 2023-11-30 Eduarda Fonseca da Nova Cruz , David Möckli

Facet inequalities play an important role in detecting the nonlocality of a quantum state. The number of such inequalities depends on the Bell test scenario. With the increase in the number of parties, measurement outcomes, or/and the…

Quantum Physics · Physics 2023-03-20 Arpan Das , Chandan Datta , Pankaj Agrawal

In quantum optics, nonclassicality of quantum states is commonly associated with negativities of phase-space quasiprobability distributions. We argue that the impossibility of any classical simulations with phase-space functions is a…

Quantum Physics · Physics 2022-01-03 A. A. Semenov , A. B. Klimov

First, we present a Bell type inequality for n qubits, assuming that m out of the n qubits are independent. Quantum mechanics violates this inequality by a ratio that increases exponentially with m. Hence an experiment on n qubits violating…

Quantum Physics · Physics 2009-10-31 N. Gisin , H. Bechmann-Pasquinucci

The aim of this thesis is to investigate quantum entanglement and quantum nonlocality of bipartite finite-dimensional systems (bipartite qudits). Entanglement is one of the most fascinating non-classical features of quantum theory, and…

Quantum Physics · Physics 2009-07-09 Christoph Spengler

Bell's theorem is 50 years old. Still there is a controversy about its implications. Much of it has its roots in confusion regarding the premises from which the theorem can be derived. Some claim that a derivation of Bell's inequalities…

Quantum Physics · Physics 2015-01-20 Marek Zukowski , Caslav Brukner

It is shown that Bell's counterfactuals admit joint quasiprobability distributions (i.e. joint distributions exist, but may not be non-negative). A necessary and sufficient condition for the existence among them of a true probability…

Quantum Physics · Physics 2007-05-23 Noam Erez

The Bell's inequalities are derived from the hypotheses of Locality, Realism and (what is lesser known) the equality between the factual and the counterfactual time averages of the expectation values of observables. The necessity of a…

Quantum Physics · Physics 2014-02-26 Alejandro A. Hnilo

The Bell inequality constrains the outcomes of measurements on pairs of distant entangled particles. The Bell contradiction states that the Bell inequality is inconsistent with the calculated outcomes of these quantum experiments. This…

Quantum Physics · Physics 2026-03-03 Kees van Hee , Kees van Berkel , Jan de Graaf

Bell inequality is a mathematical inequality derived using the assumptions of locality and realism. Its violation guarantees the existence of quantum correlations in a quantum state. Bell inequality acts as an entanglement witness in the…

Quantum Physics · Physics 2016-07-29 Kaifeng Bu , Asutosh Kumar , Junde Wu

Chen (quant-ph/0611126) has recently claimed ``exponential violation of local realism by separable states", in the sense that multi-partite separable quantum states are supposed to give rise to correlations and fluctuations that violate a…

Quantum Physics · Physics 2007-05-23 M. Seevinck

The interpretation of the meaning of Quantum Mechanics has faced controversy since its inception. Bell's inequalities are a touchstone in this controversy. Their observed violation demonstrates that at least one of the hypotheses involved…

Quantum Physics · Physics 2026-03-27 Mónica Agüero , Juliana Bordieu , Alejandro Hnilo , Marcelo Kovalsky , Myriam Nonaka

First a generalized Bell-inequality for different times and for different quasi-spin states is developed. We focus on special quasi-spin eigenstates and times. The inequality based on a local realistic theory is violated by the CP-violating…

High Energy Physics - Phenomenology · Physics 2016-09-06 B. C. Hiesmayr

Bell's [Physics 1 (1964) 195-200] theorem is popularly supposed to establish the nonlocality of quantum physics. Violation of Bell's inequality in experiments such as that of Aspect, Dalibard and Roger [Phys. Rev. Lett. 49 (1982) 1804-1807]…

Applications · Statistics 2015-02-02 Richard D. Gill