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Related papers: Quantum Non-locality and Partial Transposition for…

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We show that the relation between nonlocality and entanglement is subtler than one naively expects. In order to do this we consider the neutral kaon system--which is oscillating in time (particle--antiparticle mixing) and decaying--and…

Quantum Physics · Physics 2007-05-23 Beatrix C. Hiesmayr

Nonlocality shapes quantum correlations, revealed through the violation of Bell inequalities. The intersection of all valid Bell inequalities is the so-called local polytope. In multipartite systems, characterizing the local polytope…

Quantum Physics · Physics 2026-01-21 Jin-Fu Chen , Mengyao Hu , Jordi Tura

The correspondence principle suggests that quantum systems grow classical when large. Classical systems cannot violate Bell inequalities. Yet agents given substantial control can violate Bell inequalities proven for large-scale systems. We…

Quantum Physics · Physics 2021-02-10 Adam Bene Watts , Nicole Yunger Halpern , Aram Harrow

Quantum theory allows for correlations between the outcomes of distant measurements that are inconsistent with any locally causal theory, as demonstrated by the violation of a Bell inequality. Typical demonstrations of these correlations…

Quantum Physics · Physics 2012-02-08 Joel J. Wallman , Stephen D. Bartlett

Quantum theory violates Bell's inequality, but not to the maximum extent that is logically possible. We derive inequalities (generalizations of Cirel'son's inequality) that quantify the upper bound of the violation, both for the standard…

Quantum Physics · Physics 2009-11-07 Dennis Dieks

One of the formulations of Heisenberg uncertainty principle, concerning so-called measurement uncertainty, states that the measurement of one observable modifies the statistics of the other. Here, we derive such a measurement uncertainty…

Bell's inequality in three coupled quantum dots (QDs) within cavity QED, including Forster and exciton-phonon interactions, is investigated theoretically. For an initially entangled state, Bell's inequality is valid for certain times and…

Quantum Physics · Physics 2012-01-10 Shahpoor Moradi , Sassan Moradi

Entanglement swapping is a process by which two initially independent quantum systems can become entangled and generate nonlocal correlations. To characterize such correlations, we compare them to those predicted by bilocal models, where…

Quantum Physics · Physics 2012-03-23 Cyril Branciard , Denis Rosset , Nicolas Gisin , Stefano Pironio

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 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 show that multipartite quantum states that have a positive partial transpose with respect to all bipartitions of the particles can outperform separable states in linear interferometers. We introduce a powerful iterative method to find…

Quantum Physics · Physics 2025-04-01 Géza Tóth , Tamás Vértesi

The aim of this thesis is to investigate quantum entanglement and quantum nonlocality of bipartite finite-dimensional systems (bipartite qudits). Entanglement is one of the most fascinating non-classical features of quantum theory, and…

Quantum Physics · Physics 2009-07-09 Christoph Spengler

We analyse the recent claim that a violation of a Bell's inequality has been observed in the $B$--meson system [A. Go, {\em Journal of Modern Optics} {\bf 51} (2004) 991]. The results of this experiment are a convincing proof of quantum…

Quantum Physics · Physics 2009-11-10 A. Bramon , R. Escribano , G. Garbarino

Nonlocality is one of the key features of quantum physics, which is revealed through the violation of a Bell inequality. In large multipartite systems, nonlocality characterization quickly becomes a challenging task. A common practice is to…

Quantum Physics · Physics 2026-02-13 Mengyao Hu , Eloïc Vallée , Tim Seynnaeve , Patrick Emonts , Fatemeh Mohammadi , Jordi Tura

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

The Bell inequality is thought to be a common constraint shared by all models of local hidden variables that aim to describe the entangled states of two qubits. Since the inequality is violated by the quantum mechanical description of these…

General Physics · Physics 2020-08-05 David H. Oaknin

The characterization of a quantum system can be complicated by non-ideal measurement processes. In many systems, the underlying physical measurement is only sensitive to a single fixed state, complementary outcomes are inferred by…

Quantum Physics · Physics 2014-12-24 Kaila C. S. Hall , Daniel K. L. Oi

The ability to witness non-local correlations lies at the core of foundational aspects of quantum mechanics and its application in the processing of information. Commonly, this is achieved via the violation of Bell inequalities.…

Quantum Physics · Physics 2019-05-23 Askery Canabarro , Samuraí Brito , Rafael Chaves

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

We define a property called nondegeneracy for Bell inequalities, which describes the situation that in a Bell setting, if a Bell inequality and involved local measurements are chosen and fixed, any quantum state with a given dimension and…

Quantum Physics · Physics 2021-03-24 Zhaohui Wei , Lijinzhi Lin