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Related papers: Optimal measurements for nonlocal correlations

200 papers

Nonlocality is a fascinating and counterintuitive aspect of Nature, revealed by the violation of a Bell inequality. The standard and easiest configuration in which Bell inequalities can be measured has been proposed by…

Quantum Physics · Physics 2015-03-17 Enrico Pomarico , Jean-Daniel Bancal , Bruno Sanguinetti , Anas Rochdi , Nicolas Gisin

We show that for two-qubit chained Bell inequalities with an arbitrary number of measurement settings, nonlocality and entanglement are not only different properties but are inversely related. Specifically, we analytically prove that in…

Quantum Physics · Physics 2014-01-08 G. Vallone , G. Lima , E. S. Gómez , G. Cañas , J. -A. Larsson , P. Mataloni , A. Cabello

Certifying maximal quantum randomness without assumptions about system dimension remains a pivotal challenge for secure communication and foundational studies. Here, we introduce a generalized framework to directly certify maximal…

Quantum Physics · Physics 2025-07-15 Tianqi Zheng , Yi Li , Yu Xiang , Qiongyi He

The standard Bell inequality experiments test for violation of local realism by repeatedly making local measurements on individual copies of an entangled quantum state. Here we investigate the possibility of increasing the violation of a…

Quantum Physics · Physics 2007-05-23 Yeong-Cherng Liang , Andrew C. Doherty

Quantum nonlocality is arguably among the most counter-intuitive phenomena predicted by quantum theory. In recent years, the development of an abstract theory of nonlocality has brought a much deeper understanding of the subject. In…

One of the most notable aspects of quantum systems is that their components can exhibit correlations much stronger than those allowed by classical physics. Two examples of quantum correlations are quantum entanglement and Bell nonlocality,…

High Energy Physics - Phenomenology · Physics 2025-10-30 Matthew Low

It is well known that measurements performed on spatially separated entangled quantum systems can give rise to correlations that are non-local, in the sense that a Bell inequality is violated. They cannot, however, be used for super-luminal…

Quantum Physics · Physics 2007-10-22 Jonathan Barrett , Noah Linden , Serge Massar , Stefano Pironio , Sandu Popescu , David Roberts

In this work, we study a recently proposed operational measure of nonlocality by Fonseca and Parisio~[Phys. Rev. A 92, 030101(R) (2015)] which describes the probability of violation of local realism under randomly sampled observables, and…

Bell's theorem was a cornerstone for our understanding of quantum theory, and the establishment of Bell non-locality played a crucial role in the development of quantum information. Recently, its extension to complex networks has been…

Quantum Physics · Physics 2019-05-23 Francesco Andreoli , Gonzalo Carvacho , Luca Santodonato , Rafael Chaves , Fabio Sciarrino

Incompatible, i.e. non-jointly measurable quantum measurements are a necessary resource for many information processing tasks. It is known that increasing the number of distinct measurements usually enhances the incompatibility of a…

Quantum Physics · Physics 2023-09-28 Lucas Tendick , Hermann Kampermann , Dagmar Bruß

The violations of Bell inequalities by measurements on quantum states give rise to the phenomenon of quantum non-locality and express the advantage of using quantum resources over classical ones for certain information-theoretic tasks. The…

Quantum Physics · Physics 2020-11-30 Abderramán Amr , Carlos Palazuelos , Julio I. de Vicente

We consider relations between communication complexity problems and detecting correlations (violating local realism) with no local hidden variable model. We show first universal equivalence between characteristics of protocols used in that…

Quantum Physics · Physics 2015-10-16 L. Czekaj , A. Grudka , M. Horodecki , P. Horodecki , M. Markiewicz

Given a pair of isolated devices that accept random binary inputs and return binary outputs, a user can deduce from the observed data alone if the underlying mechanism can be explained classically. Bell's theorem further states that a…

Quantum Physics · Physics 2026-05-21 Kuntal Sengupta , Lewis Wooltorton

Incompatibility of observables, or measurements, is one of the key features of quantum mechanics, related, among other concepts, to Heisenberg's uncertainty relations and Bell nonlocality. In this manuscript we show, however, that even…

Quantum Physics · Physics 2019-05-01 Tassius Temistocles , Rafael Rabelo , Marcelo Terra Cunha

This paper is aimed to dissociate nonlocality from quantum theory. We demonstrate that the tests on violation of the Bell type inequalities are simply statistical tests of local incompatibility of observables. In fact, these are tests on…

Quantum Physics · Physics 2021-01-01 Andrei Khrennikov

Bell inequality violation is the phenomenon where multiple non-communicating parties can exhibit correlations using quantum resources that are impossible if they can only use classical resources. One way to enforce non-communication is to…

Quantum Physics · Physics 2025-10-31 Dawei Ding , Zhengfeng Ji , Pierre Pocreau , Mingze Xu , Xinyu Xu

Measurements performed on distant parts of an entangled quantum state can generate correlations incompatible with classical theories respecting the assumption of local causality. This is the phenomenon known as quantum non-locality that,…

Quantum Physics · Physics 2018-02-28 S. G. A. Brito , B. Amaral , R. Chaves

The correlations in quantum networks have attracted strong interest with new types of violations of the locality. The standard Bell inequalities cannot characterize the multipartite correlations that are generated by multiple sources. The…

Quantum Physics · Physics 2018-11-19 Ming-Xing Luo

Quantum correlations which violate a Bell inequality are presumed to power better-than-classical protocols for solving communication complexity problems (CCPs). How general is this statement? We show that violations of correlation-type Bell…

Quantum Physics · Physics 2020-09-09 Armin Tavakoli , Marek Żukowski , Časlav Brukner

Quantum nonlocality as a witness of entanglement plays a crucial role in various fields. Existing quantum monogamy relations rule out the possibility of simultaneous violations of any Bell inequalities with partial statistics generated from…

Quantum Physics · Physics 2024-03-15 Yan-Han Yang , Xin-Zhu Liu , Xing-Zhou Zheng , Shao-Ming Fei , Ming-Xing Luo