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Related papers: Combinatorics and Quantum Nonlocality

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Bell's theorem states that Local Hidden Variables (LHVs) cannot fully explain the statistics of measurements on some entangled quantum states. It is natural to ask how much supplementary classical communication would be needed to simulate…

Quantum Physics · Physics 2023-10-25 Peter Sidajaya , Aloysius Dewen Lim , Baichu Yu , Valerio Scarani

The quantum version of communication complexity allows the two communicating parties to exchange qubits and/or to make use of prior entanglement (shared EPR-pairs). Some lower bound techniques are available for qubit communication…

Computational Complexity · Computer Science 2007-05-23 Harry Buhrman , Ronald de Wolf

We consider the LOCAL model of distributed computing, where in a single round of communication each node can send to each of its neighbors a message of an arbitrary size. It is know that, classically, the round complexity of 3-coloring an…

Quantum Physics · Physics 2022-12-07 François Le Gall , Ansis Rosmanis

We present a simple hidden variable model for the singlet state of a pair of qubits, characterized by two kinds, hierarchically ordered, of hidden variables. We prove that, averaging over both types of variables, one reproduces all the…

Quantum Physics · Physics 2015-06-04 GianCarlo Ghirardi , Raffaele Romano

Two dual questions in quantum information theory are to determine the communication cost of simulating a bipartite unitary gate, and to determine their communication capacities. We present a bipartite unitary gate with two surprising…

Quantum Physics · Physics 2011-08-04 Aram W. Harrow , Debbie W. Leung

A local hidden variable model exploiting the detection loophole to reproduce exactly the quantum correlation of the singlet state is presented. The model is shown to be compatible with both the CHSH and the CH Bell inequalities. Moreover,…

Quantum Physics · Physics 2009-10-31 N. Gisin , B. Gisin

The nonlocal correlations of multipartite entangled states can be reproduced by a classical model if sufficiently many parties join together or if sufficiently many parties broadcast their measurement inputs. The maximal number m of groups…

Quantum Physics · Physics 2009-08-27 Jean-Daniel Bancal , Cyril Branciard , Nicolas Gisin , Stefano Pironio

Quantum nonlocality concerns correlations among spatially separated systems that cannot be classically explained without post-measurement communication among the parties. Thus, a natural measure of nonlocal correlations is provided by the…

Quantum Physics · Physics 2016-02-26 Alberto Montina , Stefan Wolf

We present a method to detect lower bounds to the classical capacity of quantum communication channels by means of few local measurements (i.e. without complete process tomography), reconstruction of sets of conditional probabilities, and…

Quantum Physics · Physics 2019-08-30 Chiara Macchiavello , Massimiliano F. Sacchi

We study the problem of identifying correlations in multivariate data, under information constraints: Either on the amount of memory that can be used by the algorithm, or the amount of communication when the data is distributed across…

Machine Learning · Computer Science 2018-06-07 Yuval Dagan , Ohad Shamir

We discuss models that attempt to provide an explanation for the violation of Bell inequalities at a distance in terms of hidden influences. These models reproduce the quantum correlations in most situations, but are restricted to produce…

Quantum Physics · Physics 2014-10-20 Valerio Scarani , Jean-Daniel Bancal , Antoine Suarez , Nicolas Gisin

Classical and quantum physics provide fundamentally different predictions about experiments with separate observers that do not communicate, a phenomenon known as quantum nonlocality. This insight is a key element of our present…

Quantum Physics · Physics 2017-02-17 Jonatan Bohr Brask , Rafael Chaves

I present a simple two-party quantum communication complexity protocol with higher success rate than the best possible classical protocol for the same task. The quantum protocol is shown to be equivalent to a quantum non-locality test,…

Quantum Physics · Physics 2007-05-23 Ernesto F. Galvao

Quantum entanglement is an indispensable resource for many significant quantum information processing tasks. However, because of the noise in quantum channels, it is difficult to distribute quantum entanglement over a long distance in…

Quantum Physics · Physics 2018-01-31 Zhaofeng Su , Ji Guan , Lvzhou Li

Nonlocality and its connections to entanglement are fundamental features of quantum mechanics that have found numerous applications in quantum information science. A set of correlations is said to be nonlocal if it cannot be reproduced by…

Quantum Physics · Physics 2023-11-30 Khashayar Barooti , Alexandru Gheorghiu , Grzegorz Głuch , Marc-Olivier Renou

We present relation problems whose input size is $n$ such that they can be solved with no communication for entanglement-assisted quantum communication models, but require $\Omega(n)$ qubit communication for $2$-way quantum communication…

Quantum Physics · Physics 2026-04-20 Atsuya Hasegawa , François Le Gall , Augusto Modanese

An essential component of many sophisticated metaheuristics for solving combinatorial optimization problems is some variation of a local search routine that iteratively searches for a better solution within a chosen set of immediate…

Quantum Physics · Physics 2025-02-05 M. Podobrii , V. Kuzmin , V. Voloshinov , M. Veshchezerova , M. R. Perelshtein

The demonstration and use of nonlocality, as defined by Bell's theorem, rely strongly on dealing with non-detection events due to losses and detector inefficiencies. Otherwise, the so-called detection loophole could be exploited. The only…

Quantum Physics · Physics 2016-01-20 Gilles Pütz , Nicolas Gisin

We investigate the amount of communication that must augment classical local hidden variable models in order to simulate the behaviour of entangled quantum systems. We consider the scenario where a bipartite measurement is given from a set…

Quantum Physics · Physics 2009-10-31 Gilles Brassard , Richard Cleve , Alain Tapp

A problem in quantum information theory is to find the experimental setup that maximizes the nonlocality of correlations with respect to some suitable measure such as the violation of Bell inequalities. The latter has however some…

Quantum Physics · Physics 2016-08-30 Sacha Schwarz , Andre Stefanov , Stefan Wolf , Alberto Montina