English
Related papers

Related papers: Violation of local realism vs detection efficiency

200 papers

We show using a numerical approach that gives necessary and sufficient conditions for the existence of local realism, that the bound entangled state presented in Bennett et. al. Phys. Rev. Lett. 82, 5385 (1999) admits a local and realistic…

Quantum Physics · Physics 2009-11-07 Dagomir Kaszlikowski , Marek Zukowski , Piotr Gnacinski

Bell inequalities applicable to non-ideal EPRB experiments are critical to the interpretation of experimental Bell tests. In this article it is shown that previous treatments of this subject are incorrect due to an implicit assumption and…

Quantum Physics · Physics 2015-05-12 João N. C. Especial

The universe is not locally realistic. Abandoning causality often appears more palatable than giving up on realism. This paper proposes two novel experimental setups to test realism's failure using the conservation of electric charge. The…

General Physics · Physics 2025-07-04 Victor Atanasov

This paper is aimed to dissociate nonlocality from quantum theory. We demonstrate that the tests on violation of the Bell type inequalities are simply statistical tests of local incompatibility of observables. In fact, these are tests on…

Quantum Physics · Physics 2021-01-01 Andrei Khrennikov

In an entanglement swapping process two initially uncorrelated qubits become entangled, without any direct interaction. We present a model using local variables aiming at reproducing this remarkable process, under the realistic assumption…

Quantum Physics · Physics 2013-01-22 N. Gisin , B. Gisin

We use techniques for lower bounds on communication to derive necessary conditions in terms of detector efficiency or amount of super-luminal communication for being able to reproduce with classical local hidden-variable theories the…

Quantum Physics · Physics 2016-12-30 H. Buhrman , P. Hoyer , S. Massar , H. Roehrig

For a system composed of two particles Bell's theorem asserts that averages of physical quantities determined from local variables must conform to a family of inequalities. In this work we show that a classical model containing a local…

Quantum Physics · Physics 2008-06-22 A. Matzkin

Lately, much interest has been directed towards designing setups that achieve decisive tests of local realism. Here we present Bell tests with measurements based on linear optical displacements and single-photon detection. The scheme…

Quantum Physics · Physics 2013-01-25 Jonatan Bohr Brask , Rafael Chaves

An ensemble consisting on systems of two entangled spin 1/2 particles, all of them in the same global quantum state, are considered. The two spins are measured, each of them, on a fixed direction, at two randomly selected measurement times.…

Quantum Physics · Physics 2015-03-06 Ramon Lapiedra , A. Pérez

In the present paper it is demonstrated that Bell's expression for local hidden variable correlation allows one to derive the quantum correlation. This raises questions about the use of Bell inequalities in experiments. In the paper a CHSH…

General Physics · Physics 2010-11-15 J. F Geurdes

We provide a novel criterion for identifying quantum correlation, which allows us to find connections between Bell type inequalities, entanglement detection, and correlation. We utilize the criterion to construct witness operators that can…

Quantum Physics · Physics 2007-05-23 Che-Ming Li , Li-Yi Hsu , Wei-Yang Lin , Yueh-Nan Chen , Der-San Chuu , Tobias Brandes

Quantum mechanics admits correlations that cannot be explained by local realistic models. Those most studied are the standard local hidden variable models, which satisfy the well-known Bell inequalities. To date, most works have focused on…

Quantum Physics · Physics 2017-06-01 Dylan J. Saunders , Adam J. Bennet , Cyril Branciard , Geoff J. Pryde

Mermin's observation [Phys. Rev. Lett. {\bf 65}, 1838 (1990)] that the magnitude of the violation of local realism, defined as the ratio between the quantum prediction and the classical bound, can grow exponentially with the size of the…

Quantum Physics · Physics 2009-10-29 Marco Barbieri , Francesco De Martini , Paolo Mataloni , Giuseppe Vallone , Adán Cabello

Quantum theory is inconsistent with any local hidden variable model as was first shown by Bell. To test Bell inequalities two separated observers extract correlations from a common ensemble of identical systems. Since quantum theory does…

Quantum Physics · Physics 2011-01-19 Shmuel Marcovitch , Benni Reznik

Bell's theorem supposedly demonstrates an irreconcilable conflict between quantum mechanics and local, realistic hidden variable theories. Most proofs of Bell's theorem, are based on inequalities. In this paper we present an alternative…

Quantum Physics · Physics 2025-03-10 Andrea Aiello

A family of local models containing two angles as hidden variables is defined for experiments measuring polarization correlation of optical photons. Searching for the best model of the family, that is giving predictions most close to…

Quantum Physics · Physics 2021-06-16 Emilio Santos

We examine the prevalent use of the phrase ``local realism'' in the context of Bell's Theorem and associated experiments, with a focus on the question: what exactly is the `realism' in `local realism' supposed to mean? Carefully surveying…

Quantum Physics · Physics 2009-11-13 Travis Norsen

It is shown that the detection loophole which arises when trying to rule out local realistic theories as alternatives for quantum mechanics can be closed if the detection efficiency $\eta$ is larger than $\eta \geq d^{1/2} 2^{-0.0035d}$…

Quantum Physics · Physics 2016-09-08 Serge Massar

In a Bell test, the set of observed probability distributions complying with the principle of local realism is fully characterized by Bell inequalities. Quantum theory allows for a violation of these inequalities, which is famously regarded…

Quantum Physics · Physics 2022-06-01 Mariami Gachechiladze , Bartłomiej Bąk , Marcin Pawłowski , Nikolai Miklin

The conjecture is made that quantum mechanics is compatible with local hidden variables (or local realism). The conjecture seems to be ruled out by the theoretical argument of Bell, but it is supported by the empirical fact that nobody has…

Quantum Physics · Physics 2007-05-23 Emilio Santos