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Related papers: Bell-CHSH inequality and unitary operators

200 papers

Recently, it was demonstrated by Son et al., Phys. Rev. Lett. \textbf{102}, 110404 (2009), that a separable bipartite continuous variable quantum system can violate the Clauser-Horne-Shimony-Holt (CHSH) inequality via operationally local…

Quantum Physics · Physics 2013-05-29 Mark S. Williamson , Libby Heaney , Wonmin Son

Entanglement of quantum states is absolutely essential for modern quantum sciences and technologies. It is natural to extend the notion of entanglement to quantum observables dual to quantum states. For quantum states, various separability…

Quantum Physics · Physics 2018-07-18 Ikko Hamamura

Finite dimensional representations of extended Weyl-Heisenberg algebra are studied both from mathematical and applied viewpoints. They are used to define unitary phase operator and the corresponding eigenstates (phase states). It is also…

Quantum Physics · Physics 2015-06-11 M. Daoud , E. H. El Kinani

Bounds on quantum probabilities and expectation values are derived for experimental setups associated with Bell-type inequalities. In analogy to the classical bounds, the quantum limits are experimentally testable and therefore serve as…

Quantum Physics · Physics 2007-05-23 Stefan Filipp , Karl Svozil

We propose a variation of Bell inequalities for continuous variables that employs the Wigner function and Weyl symbols of operators in phase space. We present examples of Bell inequality violation which beat Cirel'son's bound.

Quantum Physics · Physics 2012-02-14 Karl-Peter Marzlin , T. A. Osborn

We derive the lower bound of uncertainty relations of two unitary operators for a class of states based on the geometric-arithmetic inequality and Cauchy-Schwarz inequality. Furthermore, we propose a set of uncertainty relations for three…

Quantum Physics · Physics 2020-01-08 Jing Li , Sujuan Zhang , Lu Liu , Chen-Ming Bai

Three classes of entangled coherent states are employed to study the Bell-CHSH inequality. By using pseudospin operators in infinite dimensional Hilbert spaces, four dichotomic operators $(A,A',B,B')$ entering the inequality are…

Quantum Physics · Physics 2023-09-20 Philipe De Fabritiis , Fillipe M. Guedes , Giovani Peruzzo , Silvio P. Sorella

Bell inequalities, considered within quantum mechanics, can be regarded as non-optimal witness operators. We discuss the relationship between such Bell witnesses and general entanglement witnesses in detail for the Bell inequality derived…

Quantum Physics · Physics 2009-11-11 P. Hyllus , O. Guehne , D. Bruss , M. Lewenstein

Bell's theorem sets a boundary between the classical and quantum realms, by providing a strict proof of the existence of entangled quantum states with no classical counterpart. An experimental violation of Bell's inequality demands…

Imagine two parties, Alice and Bob who share an entangled quantum state. A well-established result that if Alice performs two-outcome measurement on the portion of the state in her possession and Bob does likewise, they are able to produce…

Quantum Physics · Physics 2009-11-13 T. Vértesi , K. F. Pál

Many of the standard Bell inequalities (e.g., CHSH) are not effective for detection of quantum correlations which allow for steering, because for a wide range of such correlations they are not violated. We present Bell-like inequalities…

Quantum Physics · Physics 2015-04-14 Marek Żukowski , Arijit Dutta , Zhi Yin

This study delves into the validity of quantum mechanical operators in the context of quantum gravity, recognizing the potential need for their generalization. A primary objective is to investigate the repercussions of these generalizations…

Quantum Physics · Physics 2025-02-04 Hooman Moradpour , Shahram Jalalzadeh , Hamid Tebyanian

A violation of Bell local realism inequalities in Clauser-Horn-Shimony-Holt (CHSH) form has been discovered in a relativistic GedanknExperiment. This means that there are no definite joint probabilities and this finds a classical…

General Physics · Physics 2024-06-03 Alexander Belinsky , Igor Dzhadan

We propose Bell inequalities for discrete or continuous quantum systems which test the compatibility of quantum physics with an interpretation in terms of deterministic hidden-variable theories. The wave function collapse that occurs in a…

Quantum Physics · Physics 2014-03-24 Karl-Peter Marzlin , T. A. Osborn

Bounds on the norm of quantum operators associated with classical Bell-type inequalities can be derived from their maximal eigenvalues. This quantitative method enables detailed predictions of the maximal violations of Bell-type…

Quantum Physics · Physics 2007-05-23 Stefan Filipp , Karl Svozil

We computationally investigate the complete polytope of Bell inequalities for 2 particles with small numbers of possible measurements and outcomes. Our approach is limited by Pitowsky's connection of this problem to the computationally hard…

Quantum Physics · Physics 2023-03-23 Daniel Collins , Nicolas Gisin

A cat state localized in the right Rindler wedge is employed to study the violation of the Bell-CHSH inequality in a relativistic scalar free Quantum Field Theory. By means of the bounded Hermitian operator $sign(\varphi(f))$, where…

High Energy Physics - Theory · Physics 2026-01-09 M. S. Guimaraes , I. Roditi , S. P. Sorella

The relation between Bell-CHSH violation and factorization of Hilbert space is considered here. That is, a state which is local in the sense of the Bell-CHSH inequality under a certain factorization of the underlying Hilbert space can be…

A number of papers have suggested that it is inappropriate to combine data from different experiments when undertaking experimental tests of Bell's inequalities. It has been suggested that a correct analysis, using a single probability…

Quantum Physics · Physics 2017-01-10 C M Care

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