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Related papers: Counterfactual entanglement and nonlocal correlati…

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We consider quantum systems in entangled states post-selected in non-entangled states. Such systems exhibit unusual behavior, in particular when weak measurements are performed at intermediate times.

Quantum Physics · Physics 2015-06-12 Yakir Aharonov , Shmuel Nussinov , Sandu Popescu , Lev Vaidman

Probabilities of measurement outcomes of two-particle entangled states give a physically transparent interpretation of the concurrence and of the I-concurrence as entanglement measures. The (I)-concurrence can thus be measured…

Quantum Physics · Physics 2009-11-11 Markus A. Cirone

Two important ingredients necessary for obtaining Bell nonlocal correlations between two spatially separated parties are an entangled state shared between them and an incompatible set of measurements employed by each of them. We focus on…

Quantum Physics · Physics 2025-05-26 Priya Ghosh , Chirag Srivastava , Swati Choudhary , Ujjwal Sen

We show that the ability to consider counterfactual situations is a necessary assumption of Bell's theorem, and that, to allow Bell inequality violations while maintaining all other assumptions, we just require certain measurement choices…

Quantum Physics · Physics 2024-12-25 Jonte R. Hance

We show that bipartite bound entangled states make possible violations of correlation inequalities in the prepare-and-measure scenario. These inequalities are satisfied by all classical models as well as by all quantum models that do not…

Quantum Physics · Physics 2025-03-28 Carles Roch I Carceller , Armin Tavakoli

We review the problem of discriminating entangled states from separable states for bipartite systems. We formally define what entangled states are, present some important criteria to detect entanglement, and show how they can be classified…

Quantum Physics · Physics 2007-05-23 Aditi Sen De , Ujjwal Sen , Maciej Lewenstein , Anna Sanpera

We study the relation between distillability of multipartite states and violation of Bell's inequality. We prove that there exist multipartite bound entangled states (i.e. non-separable, non-distillable states) that violate a multipartite…

Quantum Physics · Physics 2009-11-07 W. Dür

We formally prove the existence of an enduring incongruence pervading a widespread interpretation of the Bell inequality and explain how to rationally avoid it with a natural assumption justified by explicit reference to a mathematical…

Quantum Physics · Physics 2021-07-30 Justo Pastor Lambare

Complementary correlations can reveal the genuine quantum correlations present in a composite quantum system. Here we investigate the relation between complementary correlations and other aspects of genuine quantum correlations. We show…

Quantum Physics · Physics 2015-03-12 Prasenjit Deb

We introduce a sequence of numerical tests that can determine the entanglement or separability of a state even when there is not enough information to completely determine its density matrix. Given partial information about the state in the…

Quantum Physics · Physics 2012-12-14 Federico M. Spedalieri

Entangled states are notoriously non-separable, their sub-ensembles being only statistical mixtures yielding no coherences and no quantum interference phenomena. The interesting features of entangled states can be revealed only by…

Quantum Physics · Physics 2017-03-30 Stefan Ataman

While all bipartite pure entangled states are known to generate correlations violating a Bell inequality, and are therefore nonlocal, the quantitative relation between pure-state entanglement and nonlocality is poorly understood. In fact,…

Quantum Physics · Physics 2018-08-14 Victoria Lipinska , Florian Curchod , Alejandro Máttar , Antonio Acín

A correlation measure relating to measured and unmeasured local quantities in quantum mechanics is introduced, and is then applied to assess the locality implications for Bell/CHSH and similar set-ups. This leads to some interesting…

Quantum Physics · Physics 2010-04-20 Oliver Cohen

Chen (quant-ph/0611126) has recently claimed ``exponential violation of local realism by separable states", in the sense that multi-partite separable quantum states are supposed to give rise to correlations and fluctuations that violate a…

Quantum Physics · Physics 2007-05-23 M. Seevinck

In this paper, we generalize the residual entanglement to the case of multipartite states in arbitrary dimensions by making use of a new method. Through the introduction of a special entanglement measure, the residual entanglement of mixed…

Quantum Physics · Physics 2007-05-23 Chang-shui Yu , He-shan Song

Multipartite entanglement is very poorly understood despite all the theoretical and experimental advances of the last decades. Preparation, manipulation and identification of this resource is crucial for both practical and fundamental…

Quantum Physics · Physics 2015-09-28 G. H. Aguilar , S. P. Walborn , P. H. Souto Ribeiro , L. C. Céleri

Bell inequalities were meant to test quantum mechanics vs local hidden variable models, but can also be used to verify entanglement. For entanglement verification purposes one assumes the validity of quantum mechanics as well as quantum…

Quantum Physics · Physics 2015-05-13 Pavel Lougovski , S. J. van Enk

We show that any Bell local state, with a hidden nonlocality that can be revealed by local filtering, is more, or equally, entangled than nonlocal states. More precisely, it can be deterministically transformed into a nonlocal state, by…

Quantum Physics · Physics 2017-12-06 S. Camalet

We show the rather counterintuitive result that entangled input states can strictly enhance the distinguishability of two entanglement-breaking channels.

Quantum Physics · Physics 2009-11-11 Massimiliano F. Sacchi

I derive separability inequalities for Bell correlations of observables in arbitrary pure or mixed $N$ Qudit states in $D^N$-dimensional state space. I find states (a continuum of states if $D>3$) including maximally entangled states which…

Quantum Physics · Physics 2020-02-03 S. M. Roy