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Related papers: Quantum nonlocality without entanglement in a pair…

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We consider one copy of a quantum system prepared in one of two orthogonal pure states, entangled or otherwise, and distributed between any number of parties. We demonstrate that it is possible to identify which of these two states the…

Quantum Physics · Physics 2009-11-06 Jonathan Walgate , Anthony J. Short , Lucien Hardy , Vlatko Vedral

Quantum entanglement between particles is expected to allow one to perform tasks that would otherwise be impossible. In quantum sensing and metrology, entanglement is often claimed to enable a precision that cannot be attained with the same…

Quantum Physics · Physics 2023-09-06 Liam P. McGuinness

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 explore the question of using an entangled state as a universal resource for implementing quantum measurements by local operations and classical communication (LOCC). We show that for most systems consisting of three or more subsystems,…

Quantum Physics · Physics 2016-09-13 Somshubhro Bandyopadhyay , Saronath Halder , Michael Nathanson

In quantum systems, entanglement corresponds to nonclassical correlation of nonlocal observables. Thus, entanglement (or, to the contrary, separability) of a given quantum state is not uniquely determined by properties of the state, but may…

Quantum Physics · Physics 2012-05-21 Iacopo Pozzana

Suppose we want to distinguish two quantum pure states. We consider the case in which no classical knowledge on the two states is given and only a pair of samples of the two states is available. This problem is called quantum pure-state…

Quantum Physics · Physics 2008-01-07 Y. Ishida , T. Hashimoto , M. Horibe , A. Hayashi

From the consideration of measuring bipartite mixed states by separable pure states, we introduce algebraic sets in complex projective spaces for bipartite mixed states as the degenerating locus of the measurement. These algebraic sets are…

Quantum Physics · Physics 2007-05-23 Hao Chen

We address the question of whether or not global entanglement of a quantum state can be inferred from local properties. Specifically, we are interested in genuinely multiparticle entangled states whose two-body marginals are all separable,…

Quantum Physics · Physics 2018-12-05 Marius Paraschiv , Nikolai Miklin , Tobias Moroder , Otfried Gühne

Quantum data hiding is the existence of pairs of bipartite quantum states that are (almost) perfectly distinguishable with global measurements, yet close to indistinguishable when only measurements implementable with local operations and…

Quantum Physics · Physics 2025-10-07 Francesco Anna Mele , Ludovico Lami

We consider the optimal discrimination of bipartite quantum states and provide an upper bound for the maximum success probability of optimal local discrimination. We also provide a necessary and sufficient condition for a measurement to…

Quantum Physics · Physics 2022-03-16 Donghoon Ha , Jeong San Kim

The relation between entanglement and nonlocality is discussed in the case of multipartite quantum systems. We show that, for any number of parties, there exist genuinely multipartite entangled states which admit a fully local hidden…

Quantum Physics · Physics 2016-04-06 Joseph Bowles , Jérémie Francfort , Mathieu Fillettaz , Flavien Hirsch , Nicolas Brunner

Recent findings suggest, separable states, which are otherwise of no use in entanglement dependent tasks, can also be used in information processing tasks that depend upon the discord type general non classical correlations. In this work,…

Quantum Physics · Physics 2023-07-12 Ajoy Sen , Debasis Sarkar , Amit Bhar

An ensemble of product states is said to exhibit "quantum nonlocality without entanglement" if the states cannot be optimally discriminated by local operations and classical communication (LOCC). We show that this property can depend on the…

Quantum Physics · Physics 2025-06-26 Shayeef Murshid , Tathagata Gupta , Vincent Russo , Somshubhro Bandyopadhyay

There are two common settings in a quantum-state discrimination problem. One is minimum-error discrimination where a wrong guess (error) is allowed and the discrimination success probability is maximized. The other is unambiguous…

Quantum Physics · Physics 2009-11-13 A. Hayashi , T. Hashimoto , M. Horibe

We consider a quantum system subject to superselection rules, for which certain restrictions apply to the quantum operations that can be implemented. It is shown how the notion of quantum-nonlocality has to be redefined in the presence of…

Quantum Physics · Physics 2009-11-10 F. Verstraete , J. I. Cirac

One notion of non-locality in quantum theory is the fact that information may be encoded in a composite system in such a way that it is not accessible through local measurements, even with the assistance of classical communication. Thus,…

Quantum Physics · Physics 2022-10-05 Sarah Croke

We study the local indistinguishability problem of quantum states. By introducing an easily calculated quantity, non-commutativity, we present an criterion which is both necessary and sufficient for the local indistinguishability of a…

Quantum Physics · Physics 2014-09-17 Teng Ma , Ming-Jing Zhao , Yao-Kun Wang , Shao-Ming Fei

We show that there is a stronger form of bipartite quantum nonlocality in which systems that never interacted are as nonlocal as allowed by no-signaling. For this purpose, we first show that nonlocal boxes, theoretical objects that violate…

Quantum Physics · Physics 2012-11-26 Adan Cabello

In this paper we present a necessary and sufficient condition of distinguishability of bipartite quantum states. It is shown that the operators to reliably distinguish states need only rounds of projective measurements and classical…

Quantum Physics · Physics 2016-09-08 Ping-Xing Chen , Cheng-Zu Li

We consider a generalized quantum teleportation protocol for an unknown qubit using non-maximally entangled state as a shared resource. Without recourse to local filtering or entanglement concentration, using standard Bell-state measurement…

Quantum Physics · Physics 2009-11-07 Pankaj Agrawal , Arun K. Pati