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Related papers: Tight Bell inequalities from polytope slices

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Alice and Bob each have half of a pair of entangled qubits. Bob measures his half and then passes his qubit to a second Bob who measures again and so on. The goal is to maximize the number of Bobs that can have an expected violation of the…

Quantum Physics · Physics 2020-09-02 Peter J. Brown , Roger Colbeck

Contextuality and measurement incompatibility are two fundamental aspects of nonclassicality, and their manifestations in observed quantum correlations are often deeply interconnected. Recently, measurement incompatibility has been studied…

Quantum Physics · Physics 2026-04-07 Swati Kumari , Sumit Mukherjee , R. Prabhu

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

We study the nonlocality of arbitrary dimensional bipartite quantum states. By computing the maximal violation of a set of multi-setting Bell inequalities, an analytical and computable lower bound has been derived for general two-qubit…

Quantum Physics · Physics 2015-09-04 Ming Li , Tinggui Zhang , Bobo Hua , Shao-Ming Fei , Xianqing Li-Jost

We present bipartite Bell-type inequalities which allow the two partners to use some non-local resource. Such inequality can only be violated if the parties use a resource which is more non-local than the one permitted by the inequality. We…

Quantum Physics · Physics 2015-06-26 Nicolas Brunner , Valerio Scarani , Nicolas Gisin

In recent papers, the theory of representations of finite groups has been proposed to analyzing the violation of Bell inequalities. In this paper, we apply this method to more complicated cases. For two partite system, Alice and Bob each…

Quantum Physics · Physics 2017-05-16 Yanmin Yang , Zhu-Jun Zheng

We construct a set of 2^(2^n) independent Bell correlation inequalities for n-partite systems with two dichotomic observables each, which is complete in the sense that the inequalities are satisfied if and only if the correlations…

Quantum Physics · Physics 2009-11-07 R. F. Werner , M. M. Wolf

Bell inequalities are derived for any number of observers, any number of alternative setups for each one of them, and any number of distinct outcomes for each experiment. It is shown that if a physical system consists of several distant…

Quantum Physics · Physics 2007-05-23 Asher Peres

Entanglement, describing the inseparability of a quantum multiparty system, is one of the most intriguing features of quantum mechanics. Violation of Bell inequality, for ruling out the possibility of local hidden variable theories, is…

Quantum Physics · Physics 2017-04-21 Xianxin Guo , Yefeng Mei , Shengwang Du

Characterizing the set of all Bell inequalities is a notably hard task. An insightful method of solving it in case of Bell correlation inequalities for scenarios with two dichotomic measurements per site - for arbitrary number of parties -…

Nonlocality is one of the key features of quantum physics, which is revealed through the violation of a Bell inequality. In large multipartite systems, nonlocality characterization quickly becomes a challenging task. A common practice is to…

Quantum Physics · Physics 2026-02-13 Mengyao Hu , Eloïc Vallée , Tim Seynnaeve , Patrick Emonts , Fatemeh Mohammadi , Jordi Tura

In the celebrated paper [J. Phys. A: Math. Gen. 37, 1775 (2004)], D. Collins and N. Gisin presented for the first time a three setting Bell inequality (here we call it CG inequality for simplicity) which is relevant to the…

Quantum Physics · Physics 2009-02-23 Dong-Ling Deng , Zi-Sui Zhou , Jing-Ling Chen

In the Heisenberg picture of unitary quantum theory, Bell inequalities are violated with local elements of reality interacting locally. Here is how: Upon measuring her particle of the entangled pair, Alice -- like other coupled systems --…

Quantum Physics · Physics 2025-11-25 Charles Alexandre Bédard

Bell inequalities are natural tools that allow one to certify the presence of nonlocality in quantum systems. The known constructions of multipartite Bell inequalities contain, however, correlation functions involving all observers, making…

Quantum Physics · Physics 2015-03-30 J. Tura , A. B. Sainz , T. Vértesi , A. Acín , M. Lewenstein , R. Augusiak

Tight Bell inequalities are facets of Pitowsky's correlation polytope and are usually obtained from its extreme points by solving the hull problem. Here we present an alternative method based on a combination of algebraic results on…

Quantum Physics · Physics 2015-06-03 Costantino Budroni , Adan Cabello

Quantum theory allows for correlations between the outcomes of distant measurements that are inconsistent with any locally causal theory, as demonstrated by the violation of a Bell inequality. Typical demonstrations of these correlations…

Quantum Physics · Physics 2012-02-08 Joel J. Wallman , Stephen D. Bartlett

Bell's theorem shows that no hidden-variable model can explain the measurement statistics of a quantum system shared between two parties, thus ruling out a classical (local) understanding of nature. In this work we demonstrate that by…

Quantum Physics · Physics 2022-03-14 Benjamin Morris , Lukas J. Fiderer , Ben Lang , Daniel Goldwater

There exist bipartite entangled states whose violations of Clauser-Horne-Shimony-Holt (CHSH) Bell inequality can be observed by a single Alice and arbitrarily many sequential Bobs [Phys. Rev. Lett. 125, 090401 (2020)]. Here we consider its…

Quantum Physics · Physics 2023-11-08 Ya Xi Mao-Sheng Li Libin Fu , Zhu-Jun Zheng

We show that the rich structure of multipartite entanglement can be tested following a device-independent approach. Specifically we present Bell inequalities for distinguishing between different types of multipartite entanglement, without…

Quantum Physics · Physics 2015-05-30 Nicolas Brunner , James Sharam , Tamas Vertesi

Bell inequalities play a central role in certifying quantum correlations and underpin protocols such as device-independent quantum key distribution. However, enumerating all Bell inequalities for a given scenario remains intractable beyond…

Quantum Physics · Physics 2026-04-28 Christian Staufenbiel