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Related papers: Quantum nonlocality in the presence of superselect…

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For a bipartite local quantum correlation, superlocality refers to the requirement for a larger dimension of the random variable in the classical simulation protocol than that of the quantum states that generate the correlations. In this…

Quantum Physics · Physics 2018-08-02 C. Jebaratnam , Debarshi Das , Suchetana Goswami , R. Srikanth , A. S. Majumdar

Suppose we want to benchmark a quantum device held by a remote party, e.g. by testing its ability to carry out challenging quantum measurements outside of a free set of measurements $\mathcal{M}$. A very simple way to do so is to set up a…

Quantum Physics · Physics 2021-12-16 Ludovico Lami

Non-locality stands nowadays not only as one of the cornerstones of quantum theory, but also plays a crucial role in quantum information processing. Several experimental investigations of nonlocality have been carried out over the years. In…

Density matrices are the most general descriptions of quantum states, covering both pure and mixed states. Positive semidefiniteness is a physical requirement of density matrices, imposing nonnegative probabilities of measuring physical…

Quantum Physics · Physics 2024-09-11 Colm Kelleher

Quantum networks are essential for advancing scalable quantum information processing. Quantum nonlocality sharing provides a crucial strategy for the resource-efficient recycling of quantum correlations, offering a promising pathway toward…

Quantum Physics · Physics 2025-12-16 Ming-Xiao Li , Yuqi Li , Rui-Bin Xu , Mo-Ran Zhu , Haitao Ma , Chang-Yue Zhang , Zhu-Jun Zheng

When can quantum information be localized to each of a collection of spacetime regions, while also excluded from another collection of regions? We answer this question by defining and analyzing the localize-exclude task, in which a quantum…

Quantum Physics · Physics 2019-10-30 Patrick Hayden , Alex May

Nonlocality is a key feature of quantum networks and is being studied for its potential applications in quantum communication and computing. Understanding and harnessing nonlocality in quantum networks could lead to the development of…

Quantum Physics · Physics 2025-06-27 Jun-Li Jiang , Xin-Zhu Liu , Xue Yang , Xiuyong Ding , Da Zhang , Ming-Xing Luo

We study the role of entanglement and non-locality in quantum protocols that make use of systems of identical particles. Unlike in the case of distinguishable particles, the notions of entanglement and non-locality for systems whose…

Quantum Physics · Physics 2021-05-24 Fabio Benatti , Roberto Floreanini , Ugo Marzolino

We show that the quantum superluminal communication based on the quantum nonlocal influence must exist if a basic principle of science is still valid, which states that if we have demonstrated the existence of something real, we can confirm…

General Physics · Physics 2007-05-23 Gao Shan

Due to the importance of entanglement for quantum information purposes, a framework has been developed for its characterization and quantification as a resource based on the following operational principle: entanglement among $N$ parties…

Quantum Physics · Physics 2013-05-30 Rodrigo Gallego , Lars E. Würflinger , Antonio Acín , Miguel Navascués

Entanglement is an useful resource because some global operations cannot be locally implemented using classical communication. We prove a number of results about what is and is not locally possible. We focus on orthogonal states, which can…

Quantum Physics · Physics 2009-11-07 Jonathan Walgate , Lucien Hardy

Standard quantum cryptographic protocols are not secure if one assumes that nonlocal hidden variables exist and can be measured with arbitrary precision. The security can be restored if one of the communicating parties randomly switches…

Quantum Physics · Physics 2009-11-11 Diederik Aerts , Marek Czachor , Marcin Pawlowski

Nonlocality is a distinctive feature of quantum theory, which has been extensively studied for decades. It is found that the uncertainty principle determines the nonlocality of quantum mechanics. Here we show that various degrees of…

Quantum Physics · Physics 2023-06-14 Ma-Cheng Yang , Jun-Li Li , Cong-Feng Qiao

A key concept of quantum information theory is that accessing information encoded in a quantum system requires us to discriminate between several possible states the system could be in. A natural generalization of this problem, namely,…

Quantum Physics · Physics 2025-01-07 Tathagata Gupta , Shayeef Murshid , Vincent Russo , Somshubhro Bandyopadhyay

Entanglement breaking channels play a significant role in quantum information theory. In this work we investigate qubit channels through their property of `non-locality breaking', defined in a natural way but within the purview of CHSH…

Quantum Physics · Physics 2014-10-30 Rajarshi Pal , Sibasish Ghosh

Quantum state discrimination is a fundamental information processing task that serves as a building block for numerous applications and provides implications at the foundational level. In this work, we consider minimum error discrimination…

Quantum Physics · Physics 2026-04-30 Tim Achenbach , Leevi Leppäjärvi , Hanwool Lee , Teiko Heinosaari

Determination of the quantum nature of correlations between two spatially separated systems plays a crucial role in quantum information science. Of particular interest is the questions of if and how these correlations enable quantum…

Quantum Physics · Physics 2017-09-27 Farid Shahandeh , Austin P. Lund , Timothy C. Ralph

Bell's theorem basically states that local hidden variable theory cannot predict the correlations produced by quantum mechanics. It is based on the assumption that Alice and Bob can choose measurements from a measurement set containing…

Quantum Physics · Physics 2011-11-22 Yang D. Li

We exhibit an orthogonal set of product states of two three-state particles that nevertheless cannot be reliably distinguished by a pair of separated observers ignorant of which of the states has been presented to them, even if the…

Quantum entanglement and coherence are two fundamental resources for quantum information processing. Recent results clearly demonstrate their relevance in quantum technological tasks, including quantum communication and quantum algorithms.…

Quantum Physics · Physics 2018-04-16 Anurag Anshu , Rahul Jain , Alexander Streltsov