English
Related papers

Related papers: Quaternions, octonions and Bell-type inequalities

200 papers

Violation of Bell inequalities in bipartite systems represented by mutually-commuting von Neumann algebras has pioneered the study of vacuum entanglement in algebraic quantum field theory. It is unexpected that the maximal violation of Bell…

Functional Analysis · Mathematics 2026-04-16 Bingke Zheng , Shuyuan Yang , Jinchuan Hou , Kan He

The relation between Bell inequalities with two two-outcome measurements per site and distillability is analyzed in systems of an arbitrary number of quantum bits. We observe that the violation of any of these inequalities by a quantum…

Quantum Physics · Physics 2009-11-07 Antonio Acin , Valerio Scarani , Michael M. Wolf

We study Bell scenarios with binary outcomes supplemented by one bit of classical communication. We develop a method to find facet inequalities for such scenarios even when direct facet enumeration is not possible, or at least difficult.…

Quantum Physics · Physics 2019-03-27 E. Zambrini Cruzeiro , N. Gisin

We discuss the possibility of devising cosmological observables which violate Bell's inequalities. Such observables could be used to argue that cosmic scale features were produced by quantum mechanical effects in the very early universe. As…

High Energy Physics - Theory · Physics 2016-12-21 Juan Maldacena

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

We analyze the structure of correlations among more than two quantum systems. We introduce a classification of correlations based on the concept of non-separability, which is different {\em a priori} from the concept of entanglement.…

Quantum Physics · Physics 2009-11-07 Daniel Collins , Nicolas Gisin , Sandu Popescu , David Roberts , Valerio Scarani

When three or more particles are considered, quantum correlations can be stronger than the correlations generated by so-called hybrid local hidden variable models, where some of the particles are considered as a single block inside which…

Quantum Physics · Physics 2023-02-13 Fabian Bernards , Otfried Gühne

The Bell inequality is derived under the assumption of three physical data sets, random or deterministic. The data sets represent a laboratory realization of the three probability based variables used by Bell. For physical data as can be…

General Physics · Physics 2022-03-15 Louis Sica

We consider a multiphoton Bell-type inequality to study nonlocality in four-mode continuous variable systems, which goes beyond two-photon states and can be applied to mixed as well as states with fluctuating photon number. We apply the…

Quantum Physics · Physics 2021-05-05 Chandan Kumar , Gaurav Saxena , Arvind

Employing mutually-commuting von Neumann algebras to represent the algebra of observables on quantum systems provides a framework for studying quantum information theory in systems with infinite degrees of freedom and quantum field theory,…

Quantum Physics · Physics 2026-04-21 Shuyuan Yang , Jinchuan Hou , Kan He

A family of local models containing two angles as hidden variables is defined for experiments measuring polarization correlation of optical photons. Searching for the best model of the family, that is giving predictions most close to…

Quantum Physics · Physics 2021-06-16 Emilio Santos

A general matrix approach to study entangled states is presented, based on operator completeness relations. Bases of unitary operators are considered, with focus on irreducible representations of groups. Bell measurements for teleportation…

Quantum Physics · Physics 2009-11-06 G. M. D'Ariano , P. Lo Presti , M. F. Sacchi

We prove that for every Bell's inequality and for a broad class of protocols, there always exists a multi-party communication complexity problem, for which the protocol assisted by states which violate the inequality is more efficient than…

Quantum Physics · Physics 2009-11-07 Caslav Brukner , Marek Zukowski , Jian-Wei Pan , Anton Zeilinger

The difference between ideal experiments to test Bell's weak nonlocality and the real experiments leads to loopholes. Ideal experiments involve either inequalities (Bell) or equalities (Greenberger, Horne, Zeilinger). Every real experiment…

Quantum Physics · Physics 2009-11-06 Roberto M. Basoalto , Ian C. Percival

We analyze and compare the mathematical formulations of the criterion for separability for bipartite density matrices and the Bell inequalities. We show that a violation of a Bell inequality can formally be expressed as a witness for…

Quantum Physics · Physics 2009-10-31 Barbara M. Terhal

We propose a hierarchy of Bell-type inequalities for arbitrary $n$-partite systems that identify the different degrees of nonlocality ranging from standard to genuine multipartite nonlocality. After introducing the definition of…

Quantum Physics · Physics 2016-08-11 Xiaoxu Wang , Chengjie Zhang , Qing Chen , Sixia Yu , Haidong Yuan , C. H. Oh

In this work, we study a particular class of Bell inequalities involving only direct equality-comparisons of outcomes. This arises naturally when outcomes are difficult to characterize. For instance, if measurements yield smells, it may be…

Quantum Physics · Physics 2026-03-19 Ricardo Faleiro , Flavien Hirsch , Emmanuel Zambrini Cruzeiro , Nicolas Gisin

The motion of binary star systems is re-examined in the presence of perturbations from the theory of general relativity. The Kepler problem is regularized and linearized with quaternions. In this way first order perturbation results are…

General Relativity and Quantum Cosmology · Physics 2013-07-09 F. Nemes , B. Mikóczi

We explore the challenges posed by the violation of Bell-like inequalities by $d$-dimensional systems exposed to imperfect state-preparation and measurement settings. We address, in particular, the limit of high-dimensional systems,…

The question has been solved whether Bell's inequalities cover all possible kinds of hidden-variable theories. It has been shown that the given nequalities can be hardly derived when the changing space position of photon-pair source…

Quantum Physics · Physics 2007-05-23 Milos V. Lokajicek