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Related papers: Optimal measurements for nonlocal correlations

200 papers

One of the striking properties of quantum mechanics is the occurrence of the Bell-type non-locality. They are a fundamental feature of the theory that allows two parties that share an entangled quantum system to observe correlations…

Measurements in quantum theory can fail to be jointly measurable. Like entanglement, this incompatibility of measurements is necessary but not sufficient for violating Bell inequalities. The (in)compatibility relations among a set of…

Quantum Physics · Physics 2024-11-21 Shiv Akshar Yadavalli , Nikola Andrejic , Ravi Kunjwal

In this paper we study the correlations that arise when two separated parties perform measurements on systems they hold locally. We restrict ourselves to those correlations with which arbitrarily fast transmission of information is…

Quantum Physics · Physics 2009-11-11 Nick S. Jones , Lluis Masanes

We have determined numerically the maximum quantum violation of over 100 tight bipartite Bell inequalities with two-outcome measurements by each party on systems of up to four dimensional Hilbert spaces. We have found several cases,…

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

In the first part of this thesis Bell's theorem is revisited. It points at a difference between the quantum and the classical world. This difference is often behind the advantages of solutions using quantum mechanics. New and more general…

Quantum Physics · Physics 2007-08-23 Tomasz Paterek

Quantum nonlocality in networks featuring multiple independent sources underpins large-scale quantum communication and poses fundamental challenges for its characterization. In this work, we construct a family of explicit nonlinear Bell…

Quantum Physics · Physics 2025-09-08 Yao Xiao , Fenzhuo Guo , Haifeng Dong , Fei Gao

Correlations in quantum networks with independent sources exhibit a completely novel form of nonclassicality in the sense that the nonlocality of such correlations can be demonstrated in fixed local input scenarios. Before the pioneering…

Quantum Physics · Physics 2023-03-16 Kaushiki Mukherjee

We introduce a new aspect of nonlocality which arises when the task of quantum states distinguishability is considered under local operations and shared entanglement in the absence of classical communication. We find the optimal amount of…

Quantum Physics · Physics 2016-03-24 Berry Groisman , Sergii Strelchuk

The nonlocality revealed in a multiparty multisource network Bell experiment is conceptually different than the standard multiparty Bell nonlocality involving a single common source. Here, by introducing variants of asymmetric bilocal as…

Quantum Physics · Physics 2023-11-09 Souradeep Sasmal , Shyam Sundar Mahato , Alok Kumar Pan

Quantum nonlocality stands as a resource for Device Independent Quantum Information Processing (DIQIP), as, for instance, Device Independent Quantum Key Distribution. We investigate experimentally the assumption of limited Measurement…

Quantum Physics · Physics 2015-06-08 Djeylan Aktas , Sébastien Tanzilli , Anthony Martin , Gilles Pütz , Rob Thew , Nicolas Gisin

There are bipartite quantum nonlocal correlations requiring very low detection efficiency to reach the loophole-free regime but that need too many measurement settings to be practical for actual experiments. This leads to the general…

Quantum Physics · Physics 2024-02-09 Jaskaran Singh , Adán Cabello

Violation of Bell inequalities is an essential requirement for many quantum information and communication protocols. In high-dimensional systems, Bell inequality tests face the challenge of implementing genuinely multi-outcome measurements,…

Bell's theorem shows that local measurements on entangled states give rise to correlations incompatible with local hidden variable models. The degree of quantum nonlocality is not maximal though, as there are even more nonlocal theories…

Quantum Physics · Physics 2018-12-26 Cristhiano Duarte , Samuraí Brito , Barbara Amaral , Rafael Chaves

Quantum theory predicts and experiments confirm that nature can produce correlations between distant events that are nonlocal in the sense of violating a Bell inequality. Nevertheless, Bell's strong sentence {\it Correlations cry out for…

There are two powerful arguments against the possibility of extending quantum mechanics, the violation of Bell inequalities and the Kochen-Specker theorem, but the connection between the two remains confused. Following the distinctive…

Quantum Physics · Physics 2025-01-08 Jianqi Sheng , Dongkai Zhang , Lixiang Chen

Bell's theorem, stating that quantum predictions are incompatible with a local hidden variable description, is a cornerstone of quantum theory and at the center of many quantum information processing protocols. Over the years, different…

Quantum Physics · Physics 2020-05-27 I. S. Eliëns , S. G. A. Brito , R. Chaves

This work develops analytic methods to quantitatively demarcate quantum reality from its subset of classical phenomenon, as well as from the superset of general probabilistic theories. Regarding quantum nonlocality, we discuss how to…

Quantum Physics · Physics 2014-09-10 Elie Wolfe

The question of certifying quantum nonlocality under a relaxation of the assumptions in the Bell theorem has gained traction, with potential for device-independent applications under weak seeds and cross-talk. Recently, it was shown that…

Quantum Physics · Physics 2025-12-23 Ravishankar Ramanathan , Yuan Liu

We put bounds on the minimum detection efficiency necessary to violate local realism in Bell experiments. These bounds depends of simple parameters like the number of measurement settings or the dimensionality of the entangled quantum…

Quantum Physics · Physics 2007-10-22 Serge Massar , Stefano Pironio

I explain so-called quantum nonlocality experiments and discuss how to optimize them. Statistical tools from missing data maximum likelihood are crucial. New results are given on CGLMP, CH and ladder inequalities. Open problems are also…

Statistics Theory · Mathematics 2009-09-29 Richard D. Gill