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Related papers: Maximal quantum randomness in Bell tests

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We introduce a version of the chained Bell inequality for an arbitrary number of measurement outcomes, and use it to give a simple proof that the maximally entangled state of two d dimensional quantum systems has no local component. That…

Quantum Physics · Physics 2011-04-08 Jonathan Barrett , Adrian Kent , Stefano Pironio

Genuine multipartite nonlocality and nonlocality arising in networks composed of several independent sources have been separately investigated. While some genuinely entangled states cannot be verified by violating a single Bell-type…

We report on an optical setup generating more than one bit of randomness from one entangled bit (i.e. a maximally entangled state of two-qubits). The amount of randomness is certified through the observation of Bell non-local correlations.…

Quantum Physics · Physics 2018-04-18 S. Gómez , A. Mattar , E. S. Gómez , D. Cavalcanti , O. Jiménez Farías , A. Acín , G. Lima

Nonlocality lies at the core of quantum mechanics from both a fundamental and applicative point of view. It is typically revealed by a Bell test, that is by violation of a Bell inequality, whose success depends both on the state of the…

Quantum Physics · Physics 2010-10-04 Bruno Bellomo , Rosario Lo Franco , Giuseppe Compagno

While it has recently been demonstrated how to certify the maximal amount of randomness from any pure two-qubit entangled state in a device-independent way [E. Woodhead et al., Phys. Rev. Research 2, 042028(R)(2020)], the problem of optimal…

Quantum nonlocality is presented often as the most remarkable and inexplicable phenomenon known to modern science which was confirmed in the experiments proving the violation of Bell Inequalities (BI). It has been known already for a long…

Quantum Physics · Physics 2021-06-09 Marian Kupczynski

The nonlocality of certain quantum states can be revealed by using local filters before performing a standard Bell test. This phenomenon, known as hidden nonlocality, has been so far demonstrated only for a restricted class of measurements,…

Quantum Physics · Physics 2013-10-23 Flavien Hirsch , Marco Túlio Quintino , Joseph Bowles , Nicolas Brunner

We present a source of entangled photons that violates a Bell inequality free of the "fair-sampling" assumption, by over 7 standard deviations. This violation is the first experiment with photons to close the detection loophole, and we…

Quantum theory allows for nonlocality without entanglement. Notably, there exist bipartite quantum measurements consisting of only product eigenstates, yet they cannot be implemented via local quantum operations and classical communication.…

Quantum Physics · Physics 2023-07-12 Ivan Šupić , Nicolas Brunner

Bell tests---the experimental demonstration of a Bell inequality violation---are central to understanding the foundations of quantum mechanics, underpin quantum technologies, and are a powerful diagnostic tool for technological developments…

Bell nonlocality refers to correlations between two distant, entangled particles that challenge classical notions of local causality. Beyond its foundational significance, nonlocality is crucial for device-independent technologies like…

Bell inequalities have traditionally been used to demonstrate that quantum theory is nonlocal, in the sense that there exist correlations generated from composite quantum states that cannot be explained by means of local hidden variables.…

We propose an optimal numerical test for genuine multipartite nonlocality based on linear programming. In particular, we consider two non-equivalent models of local hidden variables, namely the Svetlichny and the no-signaling bilocal model.…

Quantum Physics · Physics 2022-12-28 Mahasweta Pandit , Artur Barasinski , Istvan Marton , Tamas Vertesi , Wieslaw Laskowski

Non-classical quantum correlations underpin both the foundations of quantum mechanics and modern quantum technologies. Among them, Bell nonlocality is a central example. For bipartite Bell inequalities, nonlocal correlations obey strict…

Quantum Physics · Physics 2026-05-13 Gerard Anglès Munné , Paweł Cieśliński , Jan Wójcik , Wiesław Laskowski

A proof of Bell's theorem without inequalities for two maximally entangled particles is proposed using the technique of quantum teleportation. It follows Hardy's arguments for a non-maximally entangled state with the help of two auxiliary…

Quantum Physics · Physics 2007-05-23 W. LiMing

Certification of quantum nonlocality plays a central role in practical applications like device-independent quantum cryptography and random number generation protocols. These applications entail the challenging problem of certifying quantum…

Quantum Physics · Physics 2021-07-21 S. Gómez , D. Uzcategui , I. Machuca , E. S. Gómez , S. P. Walborn , G. Lima , D. Goyeneche

Do completely unpredictable events exist in nature? Classical theory, being fully deterministic, completely excludes fundamental randomness. On the contrary, quantum theory allows for randomness within its axiomatic structure. Yet, the fact…

Experiments showing the violation of Bell inequalities have formed our belief that the world at its smallest is genuinely non-local. While many non-locality experiments use the first quantised picture, the physics of fields of…

Quantum Physics · Physics 2013-05-29 Libby Heaney , Janet Anders

Bell's theorem of 1965 is a proof that all realistic interpretations of quantum mechanics must be non-local. Bell's theorem consists of two parts: first a correlation inequality is derived that must be satisfied by all local realistic…

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

For any finite number of parts, measurements and outcomes in a Bell scenario we estimate the probability of random $N$-qu$d$it pure states to substantially violate any Bell inequality with uniformly bounded coefficients. We prove that under…

Quantum Physics · Physics 2018-02-27 Cristhiano Duarte , Raphael C. Drumond , Roberto I. Oliveira