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Related papers: Realism violates quantum mechanics

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It has been experimentally confirmed that quantum physical phenomena can violate the Information Bell Inequalities. A violation of the one or the other of these Information Bell Inequalites is equivalent to a violation of local realism…

Quantum Physics · Physics 2011-01-11 Gary Bruno Schmid , Rudolf M. Duenki

Leggett-Garg inequalities are tests of macroscopic realism that can be violated by quantum mechanics. In this letter, we realise photonic Leggett-Garg tests on a three-level system and implement measurements that admit three distinct…

Quantum Physics · Physics 2018-02-05 Kunkun Wang , Clive Emary , Xiang Zhan , Zhihao Bian , Jian Li , Peng Xue

We show that local realism applied to states characterized by a single quanta equally and coherently shared between a number of qubits (so-called W states) produces predictions incompatible with quantum theory. The origin of this…

Quantum Physics · Physics 2011-03-29 G. S. Paraoanu

Local Friendliness (LF) inequalities follow from seemingly reasonable assumptions about reality: (i) ``absoluteness of observed events'' (e.g., every observed event happens for all observers) and (ii) ``local agency'' (e.g., free choices…

Quantum Physics · Physics 2025-09-10 William J. Zeng , Farrokh Labib , Vincent Russo

Standard quantum mechanics employs complex Hilbert spaces, but whether complex numbers are fundamental or merely convenient has long been debated. For decades, real-valued equivalents were considered mathematically possible but cumbersome.…

Quantum Physics · Physics 2026-05-27 Alan C. Maioli , Evaldo M. F. Curado , Jean-Pierre Gazeau

Bell's theorem shows that local realistic theories place strong restrictions on observable correlations between different systems, giving rise to Bell's inequality which can be violated in experiments using entangled quantum states. Bell's…

We prove that for a three-qubit system in the Greenberger-Horne-Zeilinger (GHZ) state, locality per se is in conflict with the perfect GHZ correlations. The proof does not in any way use the realism assumption and can lead to a refutation…

Quantum Physics · Physics 2007-05-23 Zeng-Bing Chen , Nai-Le Liu , Sixia Yu , Yong-De Zhang

We show that quantum mechanics predicts a contradiction with local hidden variable theories for photon number measurements which have limited resolving power, to the point of imposing an uncertainty in the photon number result which is…

Quantum Physics · Physics 2009-11-06 M. D. Reid

A century after the advent of Quantum Mechanics and General Relativity, both theories enjoy incredible empirical success, constituting the cornerstones of modern physics. Yet, paradoxically, they suffer from deep-rooted, so-far intractable,…

Quantum Physics · Physics 2017-03-20 Elizabeth S. Gould , Niayesh Afshordi

We improve the test to show the impossibility of a quantum theory based on real numbers by a larger ratio of complex-to-real bound on a Bell-type parameter. In contrast to previous theoretical and experimental proposals the test requires…

Quantum Physics · Physics 2025-01-15 Josep Batle , Tomasz Białecki , Tomasz Rybotycki , Jakub Tworzydło , Adam Bednorz

In this work we show that bipartite quantum states with local Hilbert space dimension n can violate a Bell inequality by a factor of order $\sqrt{n}$ (up to a logarithmic factor) when observables with n possible outcomes are used. A central…

Quantum Physics · Physics 2015-05-14 M. Junge , C. Palazuelos , D. Perez-Garcia , I. Villanueva , M. M. Wolf

We report an exhaustive numerical analysis of violations of local realism by two qutrits in all possible pure entangled states. In Bell type experiments we allow any pairs of local unitary U(3) transformations to define the measurement…

Quantum Physics · Physics 2015-06-03 Jacek Gruca , Wieslaw Laskowski , Marek Zukowski

The machinery of quantum mechanics is fully capable of describing a single realistic world. Here we discuss the converse: in spite of appearances, and indeed numerous claims to the contrary, any quantum mechanical model can be mimicked, up…

Quantum Physics · Physics 2021-11-15 Gerard t Hooft

We have recently shown that for the special case of a bipartite system with binary inputs and outputs there exist equalities in local theories which are violated by quantum theory. The amount of white noise tolerated by these equalities are…

Quantum Physics · Physics 2008-10-16 Hossein Movahhedian

We explore quantum nonlocality in one of the simplest bipartite scenarios. Several new facet-defining Bell inequalities for the {[3 3 3] [3 3 3]} scenario are obtained with their quantum violations analyzed in details. Surprisingly, all…

Quantum Physics · Physics 2018-05-16 Sacha Schwarz , Bänz Bessire , André Stefanov , Yeong-Cherng Liang

We show that EPR's criterion of reality leads to contradictions in quantum mechanics. When locality is assumed, an inequality involving only one particle is violated, while when parameter and outcome dependence are assumed, EPR-realism is…

Quantum Physics · Physics 2013-02-05 Florin Moldoveanu

The concept of realism in quantum mechanics means that results of measurement are caused by physical variables, hidden or observable. Local hidden variables were proved unable to explain results of measurements on entangled particles tested…

Quantum Physics · Physics 2021-09-14 Sofia Wechsler

Mermin inequalities are derived for systems of three-state particles (qutrits) employing three local measurement settings. These establish perfect correlations which violate local realistic bounds more strongly than those previously…

Quantum Physics · Physics 2020-01-20 Jay Lawrence

With basis on (i) the physical principle of local causality and (ii) a certain notion of elements of reality, Einstein, Podolsky, and Rosen (EPR) put forward an argument showing that physical instances may exist in which two non-commuting…

Quantum Physics · Physics 2024-08-30 R. A. Caetano , R. M. Angelo

A standard approach in the foundations of quantum mechanics studies local realism and hidden variables models exclusively in terms of violations of Bell-like inequalities. Thus quantum nonlocality is tied to the celebrated no-go theorems,…

Quantum Physics · Physics 2007-05-23 James D. Malley , Arthur Fine