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Related papers: Information-based measure of nonlocality

200 papers

Quantum non-locality is normally defined via violations of Bell's inequalities that exclude certain classical hidden variable theories from explaining quantum correlations. Another definition of non-locality refers to the wave-function…

Quantum Physics · Physics 2018-08-01 Armen E. Allahverdyan , Arshag Danageozian

The use of Bell's theorem in any application or experiment relies on the assumption of free choice or, more precisely, measurement independence, meaning that the measurements can be chosen freely. Here, we prove that even in the simplest…

Quantum Physics · Physics 2016-11-25 Gilles Pütz , Denis Rosset , Tomer Jack Barnea , Yeong-Cherng Liang , Nicolas Gisin

Quantum nonlocality is arguably among the most counter-intuitive phenomena predicted by quantum theory. In recent years, the development of an abstract theory of nonlocality has brought a much deeper understanding of the subject. In…

Recent work has extended Bell's theorem by quantifying the amount of communication required to simulate entangled quantum systems with classical information. The general scenario is that a bipartite measurement is given from a set of…

Quantum Physics · Physics 2009-11-06 Serge Massar , Dave Bacon , Nicolas Cerf , Richard Cleve

We consider relations between communication complexity problems and detecting correlations (violating local realism) with no local hidden variable model. We show first universal equivalence between characteristics of protocols used in that…

Quantum Physics · Physics 2015-10-16 L. Czekaj , A. Grudka , M. Horodecki , P. Horodecki , M. Markiewicz

The simulation of quantum correlations with alternative nonlocal resources, such as classical communication, gives a natural way to quantify their nonlocality. While multipartite nonlocal correlations appear to be useful resources, very…

Quantum Physics · Physics 2011-07-07 Cyril Branciard , Nicolas Gisin

It has recently been shown that all causal correlations between two parties which output each one bit, a and b, when receiving each one bit, x and y, can be expressed as convex combinations of local correlations (i.e., correlations that can…

Quantum Physics · Physics 2009-11-10 N. J. Cerf , N. Gisin , S. Massar , S. Popescu

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

We experimentally demonstrate the superior discrimination of separated, unentangled two-qubit correlated states using nonlocal measurements, when compared with measurements based on local operations and classical communications. When…

Quantum Physics · Physics 2008-11-26 G. J. Pryde , J. L. O'Brien , A. G. White , Stephen D. Bartlett

Quantum systems that have never interacted can become nonlocally correlated through a process called entanglement swapping. To characterize nonlocality in this context, we introduce local models where quantum systems that are initially…

Quantum Physics · Physics 2010-04-27 Cyril Branciard , Nicolas Gisin , Stefano Pironio

In order to understand whether nonlocality implies information transfer, a quantum optical experimental test, well within the scope of current technology, is proposed. It is essentially a delayed choice experiment as applied to entangled…

Quantum Physics · Physics 2007-05-23 R. Srikanth

Simulating quantum nonlocality and steering requires augmenting pre-shared randomness with non-vanishing communication cost. This prompts the question of how one may provide such an operational characterization for the quantumness of…

Quantum Physics · Physics 2017-03-22 C. Jebaratnam , S. Aravinda , R. Srikanth

Recent works in foundations of quantum (field) theory and relativistic quantum information try to better grasp the interplay between the structure of quantum correlations and the constraints imposed by causality on physical operations.…

Quantum Physics · Physics 2015-10-14 Issam Ibnouhsein

Nonlocality, evidenced by the violation of Bell inequalities, not only signifies entanglement but also highlights measurement incompatibility in quantum systems. Utilizing the generalized Clauser-Horne-Shimony-Holt (CHSH) Bell inequality,…

Quantum networks allow in principle for completely novel forms of quantum correlations. In particular, quantum nonlocality can be demonstrated here without the need of having various input settings, but only by considering the joint…

The generation of (Bell-)nonlocal correlations, i.e., correlations leading to the violation of a Bell-like inequality, requires the usage of a nonlocal resource, such as an entangled state. When given a correlation (a collection of…

Quantum Physics · Physics 2015-03-19 Florian John Curchod , Nicolas Gisin , Yeong-Cherng Liang

Bell nonlocality and uncertainty relations are distinct features of quantum theory from classical physics. Bell nonlocality concerns the correlation strength among local observables on different quantum particles, whereas the uncertainty…

Quantum Physics · Physics 2024-09-10 Li-Yi Hsu

We introduce a new aspect of nonlocality which arises when the task of quantum states distinguishability is considered under local operations and shared entanglement in the absence of classical communication. We find the optimal amount of…

Quantum Physics · Physics 2016-03-24 Berry Groisman , Sergii Strelchuk

Nonlocality, as established by seminal Bell's theorem, is considered to be the most striking feature of correlations present in space like separated events. Its practical application in device independent protocols, such as secure key…

In the first part of this thesis Bell's theorem is revisited. It points at a difference between the quantum and the classical world. This difference is often behind the advantages of solutions using quantum mechanics. New and more general…

Quantum Physics · Physics 2007-08-23 Tomasz Paterek