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Related papers: Optimal measurements for nonlocal correlations

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The presence of Bell-nonlocality in the correlations arising from measuring spatially-separated systems guarantees that the sets of measurements used are necessarily incompatible. Not all sets of incompatible measurements can however lead…

Quantum Physics · Physics 2025-08-21 Andrés F. Ducuara , Patryk Lipka-Bartosik , Cristian E. Susa , Paul Skrzypczyk

We introduce a permutationally invariant multipartite Bell inequality for many-body three-level systems and use it to investigate a connection between Bell nonlocality and (lack of) quantum chaos. An associated Bell operator is then defined…

Quantum Physics · Physics 2026-04-08 Albert Aloy , Guillem Müller-Rigat , Maciej Lewenstein , Jordi Tura , Matteo Fadel

Bell nonlocality plays a fundamental role in quantum theory. Numerous tests of the Bell inequality have been reported since the ground-breaking discovery of the Bell theorem.Up to now, however, most discussions of the Bell scenario have…

Quantum Physics · Physics 2018-11-08 Meng-Jun Hu , Zhi-Yuan Zhou , Xiao-Min Hu , Chuan-Feng Li , Guang-Can Guo , Yong-Sheng Zhang

Relativity theory severely restricts the ability to perform nonlocal measurements in quantum mechanics. Studying such nonlocal schemes may thus reveal insights regarding the relations between these two fundamental theories. Therefore, for…

Quantum incompatibility, referred as the phenomenon that some quantum measurements cannot be performed simultaneously, is necessary for various quantum information processing tasks, such as nonlocality and steering. When these applications…

Quantum Physics · Physics 2024-11-19 Xiaolin Zhang , Rui Qu , Zehong Chang , Yunlong Wang , Zhenyu Guo , Min An , Hong Gao , Fuli Li , Pei Zhang

Bell inequalities are mathematical constructs that demarcate the boundary between quantum and classical physics. A new class of multiplicative Bell inequalities originating from a volume maximization game (based on products of correlators…

The uncertainty principle may be considered as giving rise to the notion of incompatibility of observables. A pack of quantum measurements that cannot be measured simultaneously is said to form a set of incompatible measurements. Every set…

Quantum Physics · Physics 2024-01-19 Kornikar Sen , Saronath Halder , Ujjwal Sen

Bell's inequality sets a strict threshold for how strongly correlated the outcomes of measurements on two or more particles can be, if the outcomes of each measurement are independent of actions undertaken at arbitrarily distant locations.…

Quantum Physics · Physics 2022-05-24 David I. Kaiser

Bell's theorem teaches us that there are quantum correlations that can not be simulated by just shared randomness (Local Hidden variable). There are some recent results which simulate singlet correlation by using either 1 cbit or a binary…

Quantum Physics · Physics 2013-11-18 Manik Banik , MD Rajjak Gazi , Subhadipa Das , Ashutosh Rai , Samir Kunkri

The certification of Bell nonlocality or quantum steering implies the use of incompatible measurements. Here we make this connection quantitative. We show how to strengthen robustness-based steering and nonlocality quantifiers in order that…

Quantum Physics · Physics 2016-06-07 Daniel Cavalcanti , Paul Skrzypczyk

We analyze nonclassical correlations between outcomes of measurements conducted on two spatial radiation modes. These correlations cannot be simulated with statistical mixtures of coherent states or, more generally, with non-negative…

Quantum Physics · Physics 2022-07-01 V. S. Kovtoniuk , I. S. Yeremenko , S. Ryl , W. Vogel , A. A. Semenov

Measurement uncertainty relations are lower bounds on the errors of any approximate joint measurement of two or more quantum observables. The aim of this paper is to provide methods to compute optimal bounds of this type. The basic method…

Quantum Physics · Physics 2016-06-08 René Schwonnek , David Reeb , Reinhard F. Werner

An important problem in quantum information theory is that of bounding sets of correlations that arise from making local measurements on entangled states of arbitrary dimension. Currently, the best-known method to tackle this problem is the…

Quantum Physics · Physics 2020-10-21 Joseph Bowles , Flavio Baccari , Alexia Salavrakos

According to Bell's theorem, any model based on local variables cannot reproduce certain quantum correlations. A critical question is whether one could devise an alternative framework, based on nonlocal variables, to reproduce quantum…

Quantum Physics · Physics 2025-01-07 Jianqi Sheng , Dongkai Zhang , Lixiang Chen

We provide a method to describe quantum nonlocality for $n$-qubit systems. By treating the correlation function as an $n$-index tensor, we derive a generalized Bell inequality. Taking generalized Greenberger-Horne-Zeilinger (GHZ) state for…

Quantum Physics · Physics 2021-05-11 Dong Ding , Yingqiu He , Fengli Yan , Ting Gao

The experimental violation of Bell inequalities using spacelike separated measurements precludes the explanation of quantum correlations through causal influences propagating at subluminal speed. Yet, any such experimental violation could…

The question of how large Bell inequality violations can be, for quantum distributions, has been the object of much work in the past several years. We say that a Bell inequality is normalized if its absolute value does not exceed 1 for any…

Quantum Physics · Physics 2018-06-11 Sophie Laplante , Mathieu Laurière , Alexandre Nolin , Jérémie Roland , Gabriel Senno

Quantum correlation between nodes in a network which consist of several independent sources of entanglement and in multipartite entanglement systems are important for general understanding of the nature of nonlocality, quantum information…

Quantum Physics · Physics 2022-01-25 E. Håkansson , A. Piveteau , S. Muhammad , M. Bourennane

Nonlocality plays a fundamental role in quantum information science. Recently, it has been theoretically predicted and experimentally demonstrated that the nonlocality of an entangled pair may be shared among multiple observers using weak…

Quantum Physics · Physics 2020-10-06 Tianfeng Feng , Changliang Ren , Yuling Tian , Maolin Luo , Haofei Shi , Jingling Chen , Xiaoqi Zhou

In the analysis of experiments designed to reveal violation of Bell-type inequalities, it is usually assumed that any hidden variables associated with the nth particle pair would be independent of measurement choices and outcomes for the…

Quantum Physics · Physics 2009-11-07 Jonathan Barrett , Daniel Collins , Lucien Hardy , Adrian Kent , Sandu Popescu