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Related papers: Causality, Joint measurement and Tsirelson's bound

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We study a class of Bell inequalities and find their maximum quantum violation. These inequalities involve n parties, two measurements per party, with each measurement having two outcomes. The n=2 case corresponds to the CH inequality. We…

Quantum Physics · Physics 2013-05-30 V. Ugur Guney , Mark Hillery

The Suppes-Zanotti inequalities involving the joint expectations of just three binary quantum observables are (re-)derived by the hull computation of the respective correlation polytope. A min-max calculation reveals its maximal quantum…

Quantum Physics · Physics 2021-07-02 Karl Svozil

We consider the problem of distinguishing between a set of arbitrary quantum states in a setting in which the time available to perform the measurement is limited. We provide simple upper bounds on how well we can perform state…

Quantum Physics · Physics 2015-05-28 Andrew C. Doherty , Stephanie Wehner

Entanglement in quantum mechanics contradicts local realism, and is a manifestation of quantum non-locality. Its presence can be detected through the violation of Bell, or CHSH inequalities. Paradigmatic quantum systems provide examples of…

Mesoscale and Nanoscale Physics · Physics 2017-10-25 Alessandro Romito , Yuval Gefen

A parametrization of density matrices of $d$ dimensions in terms of the raising $J_+$ and lowering $J_-$ angular momentum operators is established together with an implicit connection with the generalized Bloch-GellMann parameters. A…

Quantum Physics · Physics 2024-11-27 J. A. López-Saldívar , O. Castaños , S. Cordero , R. López-Peña , E. Nahmad-Achar

The discipline of parallelization in the manifold of all possible measurement results is shown to be responsible for the existence of all quantum correlations, with the upper bound on their strength stemming from the maximum of possible…

Quantum Physics · Physics 2011-01-13 Joy Christian

The principle called information causality has been used to deduce Tsirelson's bound. In this paper we derive information causality from monotonicity of divergence and relate it to more basic principles related to measurements on…

Quantum Physics · Physics 2020-02-10 Peter Harremoës

For a nonseparable bipartite quantum state violating the Clauser-Horne-Shimony-Holt (CHSH) inequality, we evaluate amounts of noise breaking the quantum character of its statistical correlations under any generalized quantum measurements of…

Quantum Physics · Physics 2007-05-23 Elena R. Loubenets

We present an alternative definition of quantum entanglement for bipartite system based on Bell inequality and operators' noncommutativity. A state is said to be entangled, if the maximum of CHSH expectation value $F_{\max}$ is obtain by…

Quantum Physics · Physics 2007-05-23 Li-Bin Fu , Jing-Ling Chen , Xian-Geng Zhao , Shi-Gang Chen

Quantum correlations are the singular, defining resource of quantum information science and metrology, forming the basis of every operational advantage that quantum systems hold over classical ones. Yet exact bounds on these…

Quantum Physics · Physics 2025-12-22 Samuel Alperin

We give strong evidence that divisibility of qubit quantum processes implies temporal Tsirelson's bound. We also give strong evidence that the classical bound of the temporal Bell's inequality holds for dynamics that can be described by…

Quantum Physics · Physics 2017-01-10 Thao Le , Felix A. Pollock , Tomasz Paterek , Mauro Paternostro , Kavan Modi

We present the new exact upper bounds on the maximal Bell violation for the generalized N-qubit GHZ state, the N-qudit GHZ state and, in general, for an arbitrary N-partite quantum state, possibly infinite-dimensional. Our results indicate…

Quantum Physics · Physics 2011-08-02 Elena R. Loubenets

We present a generalized Bell inequality for two entangled quNits. On one quNit the choice is between two standard von Neumann measurements, whereas for the other quNit there are $N^2$ different binary measurements. These binary…

Quantum Physics · Physics 2007-05-23 H. Bechmann-Pasquinucci , N. Gisin

In a recent article [Phys. Rev. A 54, 1793 (1996)] Krenn and Zeilinger investigated the conditional two-particle correlations for the subensemble of data obtained by selecting the results of the spin measurements by two observers 1 and 2…

Quantum Physics · Physics 2008-12-18 Jose L. Cereceda

A long-standing problem in the foundations of quantum mechanics is to identify a physical principle that explains why algebraically maximal violations of Bell inequalities can generally not be achieved in Nature. One recently proposed…

Quantum Physics · Physics 2026-03-24 Lionel J. Dmello , David Gross

When a collection of distant observers share an entangled quantum state, the statistical correlations among their measurements may violate a many-body Bell inequality, demonstrating a non-local behavior. Focusing on the Ising model in a…

Strongly Correlated Electrons · Physics 2019-10-25 Angelo Piga , Albert Aloy , Maciej Lewenstein , Irénée Frérot

The correlations between two qubits belonging to a three-qubit system can violate the Clauser-Horne-Shimony-Holt-Bell inequality beyond Cirel'son's bound [A. Cabello, Phys. Rev. Lett. 88, 060403 (2002)]. We experimentally demonstrate such a…

Quantum Physics · Physics 2007-05-23 Yu-Ao Chen , Tao Yang , An-Ning Zhang , Zhi Zhao , Adan Cabello , Jian-Wei Pan

Measurements on entangled quantum states can produce outcomes that are nonlocally correlated. But according to Tsirelson's theorem, there is a quantitative limit on quantum nonlocality. It is interesting to explore what would happen if…

Quantum Physics · Physics 2010-04-14 Anthony J. Short , Jonathan Barrett

This paper examines a quantitative and optimal lower bound on the detector efficiency in a (2,2,2) Bell experiment within a fully device-independent framework, whereby the detectors used in the experiment are uncharacterized. We provide a…

Quantum Physics · Physics 2025-11-25 Arkaprabha Ghosal , Soumyadip Patra , Peter Bierhorst

In standard formulations of the uncertainty principle, two fundamental features are typically cast as impossibility statements: two noncommuting observables cannot in general both be sharply defined (for the same state), nor can they be…

Quantum Physics · Physics 2018-06-08 Tom Bullock , Paul Busch