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Related papers: Maximal quantum randomness in Bell tests

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We propose a single-particle experiment that is equivalent to the conventional two-particle experiment used to demonstrate a violation of Bell's inequalities. Hence, we argue that quantum mechanical nonlocality can be demonstrated by…

Quantum Physics · Physics 2013-05-29 G. Bjork , P. Jonsson , L. L. Sanchez-Soto

Quantum mechanics is a nonlocal theory, but not as nonlocal as the no-signalling principle allows. However, there exist quantum correlations that exhibit maximal nonlocality: they are as nonlocal as any non-signalling correlations and thus…

We show that arbitrary functions of continuous variables, e.g. position and momentum, can be used to generate tests that distinguish quantum theory from local hidden variable theories. By optimising these functions, we obtain more robust…

Quantum Physics · Physics 2009-11-16 Q. Y. He , E. G. Cavalcanti , M. D. Reid , P. D. Drummond

A proof of Bell's theorem using two maximally entangled states of two qubits is presented. It exhibits a similar logical structure to Hardy's argument of ``nonlocality without inequalities''. However, it works for 100% of the runs of a…

Quantum Physics · Physics 2009-11-06 Adan Cabello

Recently, a group of experiments tested local realism with random choices prepared by humans. These various tests were subject to additional assumptions, which lead to loopholes in the interpretations of almost all of the experiments. Among…

Quantum Physics · Physics 2020-09-08 Stanisław Sołtan , Dawid Dopierała , Adam Bednorz

Incompatibility of observables, or measurements, is one of the key features of quantum mechanics, related, among other concepts, to Heisenberg's uncertainty relations and Bell nonlocality. In this manuscript we show, however, that even…

Quantum Physics · Physics 2019-05-01 Tassius Temistocles , Rafael Rabelo , Marcelo Terra Cunha

Adopting the frame of mesoscopic physics, we describe a Bell type experiment involving time-delayed two-particle correlation measurements. The indistinguishability of quantum particles results in a specific interference between different…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 A. V. Lebedev , G. Blatter

Bell inequalities reveal the fundamentally nonlocal character of quantum mechanics. In this regard, one of the interesting problems is to explore all possible Bell inequalities that demonstrate a gap between local and nonlocal quantum…

Quantum Physics · Physics 2026-02-10 Palash Pandya , Shubhayan Sarkar , Remigiusz Augusiak

Successful realization of Bell tests has settled an 80-year-long debate, proving the existence of correlations which cannot be explained by a local realistic model. Recent experimental progress allowed to rule out any possible loopholes in…

The Bell inequality constrains the outcomes of measurements on pairs of distant entangled particles. The Bell contradiction states that the Bell inequality is inconsistent with the calculated outcomes of these quantum experiments. This…

Quantum Physics · Physics 2026-03-03 Kees van Hee , Kees van Berkel , Jan de Graaf

As quantum technologies continue to advance rapidly, the device-independent testing of the functioning of a quantum device has become increasingly important. Self-testing, a correlation based protocol, enables such certification of a…

Quantum Physics · Physics 2024-08-21 Ritesh K. Singh , Souradeep Sasmal , A. K. Pan

By performing local projective measurements on a two-qubit entangled state one can certify in a device-independent way up to one bit of randomness. We show here that general measurements, defined by positive-operator-valued measures, can…

Quantum Physics · Physics 2016-04-20 Antonio Acín , Stefano Pironio , Tamás Vértesi , Peter Wittek

To date, most efforts to demonstrate quantum nonlocality have concentrated on systems of two (or very few) particles. It is however difficult in many experiments to address individual particles, making it hard to highlight the presence of…

We derive tight quadratic inequalities for all kinds of hybrid separable-inseparable $n$-particle density operators on an arbitrary dimensional space. This methodology enables us to truly derive a tight quadratic inequality as tests for…

Quantum Physics · Physics 2009-11-07 Koji Nagata , Masato Koashi , Nobuyuki Imoto

Quantum technologies offer significant advancements in information processing and communication, notably in the domain of random number generation (RNG). The use of Bell inequalities enables users to certify the randomness of outputs…

Quantum Physics · Physics 2025-12-01 Robert Okuła , Piotr Mironowicz

It is now a well-known fact that the correlations arising from local dichotomic measurements on an entangled quantum state may exhibit intrinsically non-classical features. In this paper we delve into a comprehensive study of random…

Bell inequalities define experimentally observable quantities to detect non-locality. In general, they involve correlation functions of all the parties. Unfortunately, these measurements are hard to implement for systems consisting of many…

Quantum Physics · Physics 2014-07-14 J. Tura , R. Augusiak , A. B. Sainz , T. Vértesi , M. Lewenstein , A. Acín

Certification of quantum systems and their properties has become a field of intensive studies. Here, taking advantage of the one-sided device-independent scenario (known also as quantum steering scenario), we propose a self-testing scheme…

The question whether Quantum Mechanics describes all aspects of both the micro-world of elementary particles and living organisms adequately is still open. A Bell inequality test without locality and detection loopholes will deliver the…

Quantum Physics · Physics 2010-08-26 M. Stobińska , P. Horodecki , A. Buraczewski , R. W. Chhajlany , R. Horodecki , G. Leuchs

Non-local correlations that obey the no-signalling principle contain intrinsic randomness. In particular, for a specific Bell experiment, one can derive relations between the amount of randomness produced, as quantified by the min-entropy…

Quantum Physics · Physics 2019-05-07 Boris Bourdoncle , Pei-Sheng Lin , Denis Rosset , Antonio Acín , Yeong-Cherng Liang