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Related papers: An anomaly of non-locality

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The hybrid entangled states generated, e.g., in a trapped-ion or atom-cavity system, have exactly one ebit of entanglement, but are not maximally entangled. We demonstrate this by showing that they violate, but in general do not maximally…

Quantum Physics · Physics 2009-11-07 Zeng-Bing Chen , Guang Hou , Yong-De Zhang

Quantum nonlocality is usually associated with entangled states by their violations of Bell-type inequalities. However, even unentangled systems, whose parts may have been prepared separately, can show nonlocal properties. In particular, a…

Quantum Physics · Physics 2019-02-06 Saronath Halder , Manik Banik , Sristy Agrawal , Somshubhro Bandyopadhyay

Although entanglement is widely recognized as one of the most fascinating characteristics of quantum mechanics, nonlocality remains to be a big labyrinth. The proof of existence of nonlocality is as yet not much convincing because of its…

Quantum Physics · Physics 2007-05-23 Zeng-Bing Chen , Sixia Yu , Yong-De Zhang , Nai-Le Liu

The unique entanglement measure is concurrence in a 2-qubit pure state. The maximum violation of Bell's inequality is monotonically increasing for this quantity. Therefore, people expect that pure state entanglement is relevant to the…

Quantum Physics · Physics 2022-12-14 Xingyu Guo , Chen-Te Ma

We review some counterintuitive properties of standard measures describing quantum entanglement and violation of Bell's inequality (often referred to as "nonlocality") in two-qubit systems. By comparing the nonlocality, negativity,…

Quantum Physics · Physics 2020-01-10 Adam Miranowicz , Bohdan Horst , Andrzej Koper

Quantum nonlocality without entanglement is a fantastic phenomenon in quantum theory. This kind of quantum nonlocality is based on the task of local discrimination of quantum states. Recently, Bandyopadhyay and Halder [Phys. Rev. A 104,…

Quantum Physics · Physics 2022-05-11 Mao-Sheng Li , Zhu-Jun Zheng

Ensembles containing orthogonal product states are found to be indistinguishable under local operations and classical communication (LOCC), thereby showing irreversibility in the preparation and distinguishing processes, which is commonly…

Quantum Physics · Physics 2020-09-10 Shiladitya Mal , Aditi Sen De

Bell inequalities have traditionally been used to demonstrate that quantum theory is nonlocal, in the sense that there exist correlations generated from composite quantum states that cannot be explained by means of local hidden variables.…

Quantum entanglement and nonlocality are inequivalent notions: There exist entangled states that nevertheless admit local-realistic interpretations. This paper studies a special class of local-hidden-variable theories, in which the linear…

Quantum Physics · Physics 2017-11-17 Bin Yan

Here we deal with a nonlocality argument proposed by Cabello which is more general than Hardy's nonlocality argument but still maximally entangled states do not respond. However, for most of the other entangled states maximum probability of…

Quantum Physics · Physics 2009-11-11 Samir Kunkri , Sujit K. Choudhary , Ali Ahanj , Promod Joag

Nonlocality, manifested by the violation of Bell inequalities, indicates entanglement within a joint quantum system. A natural question is how much entanglement is required for a given nonlocal behavior. Here, we explore this question by…

Quantum Physics · Physics 2025-06-23 Yuwei Zhu , Xingjian Zhang , Xiongfeng Ma

We demonstrate that, in the tripartite scenario with all parties' local events being space-like separated, Hardy-type nonlocality constitutes a stronger manifestation of nonlocal correlations than those captured by Mermin-type inequalities,…

Quantum Physics · Physics 2025-04-29 Ranendu Adhikary , Souradeep Sasmal , Arup Roy

While all bipartite pure entangled states violate some Bell inequality, the relationship between entanglement and non-locality for mixed quantum states is not well understood. We introduce a simple and efficient algorithmic approach for the…

Quantum Physics · Physics 2009-11-07 Barbara M. Terhal , Andrew C. Doherty , David Schwab

Nonlocal nature apparently shown in entanglement is one of the most striking features of quantum theory. We examine the locality assumption in Bell-type proofs for entangled qubits, i.e. the outcome of a qubit at one end is independent of…

Quantum Physics · Physics 2009-03-23 Daegene Song

We show that for two-qubit chained Bell inequalities with an arbitrary number of measurement settings, nonlocality and entanglement are not only different properties but are inversely related. Specifically, we analytically prove that in…

Quantum Physics · Physics 2014-01-08 G. Vallone , G. Lima , E. S. Gómez , G. Cañas , J. -A. Larsson , P. Mataloni , A. Cabello

The discrepancy between maximally entangled states and maximally non-classical quantum correlations is well-known but still not well understood. We aim to investigate the relation between quantum correlations and entanglement in a family…

Quantum Physics · Physics 2016-03-01 Armin Tavakoli , Stefan Zohren , Marcin Pawlowski

Bell showed 50 years ago that quantum theory is nonlocal via his celebrated inequalities, turning the issue of quantum nonlocality from a matter of taste into a matter of test. Years later, Hardy proposed a test for nonlocality without…

Quantum Physics · Physics 2014-10-13 Sixia Yu

While entanglement and violation of Bell inequalities were initially thought to be equivalent quantum phenomena, we now have different examples of entangled states whose correlations can be described by local hidden--variable models and,…

Quantum Physics · Physics 2015-03-30 Remigiusz Augusiak , Maciej Demianowicz , Antonio Acín

Investigating a class of models that is familiar in studies of cellular automata, we find that quantum operators can be employed to describe their long distance behavior. These operators span a Hilbert space that appears to turn such a…

Quantum Physics · Physics 2009-08-25 Gerard 't Hooft

A fruitful way of studying physical theories is via the question whether the possible physical states and different kinds of correlations in each theory can be shared to different parties. Over the past few years it has become clear that…

Quantum Physics · Physics 2010-04-15 Michael Seevinck