English
Related papers

Related papers: Bell inequality for qubits based on the Cauchy-Sch…

200 papers

In this article, we present several inequalities treating operator means and the Cauchy-Schwarz inequality. In particular, we present some new comparisons between operator Heron and Heinz means, several generalizations of the difference…

Functional Analysis · Mathematics 2021-07-23 Y. Kapil , C. Conde , M. S. Moslehian , M. Singh , M. Sababheh

We use two different approaches to derive multipartite Leggett-type inequalities, which are generalizations of the two-qubit Leggett-type inequality obtained in [Nature Phys. \textbf{4}, 681 (2008)]. The first approach is based on the…

Quantum Physics · Physics 2011-11-18 Dong-Ling Deng , Chunfeng Wu , Jing-Ling Chen , C. H. Oh

We describe a method of extending Bell inequalities from $n$ to $n+1$ parties and formulate sufficient conditions for our method to produce tight inequalities from tight inequalities. The method is non trivial in the sense that the…

Quantum Physics · Physics 2008-05-06 Yu-Chun Wu , Piotr Badziag , Marcin Wieśniak , Marek Żukowski

Some new reverses of the Cauchy-Schwarz inequality in inner product spaces are presented in this paper.The results obtained here complement the recent work of the references.

Functional Analysis · Mathematics 2007-05-23 Gong-bao Wamg , Ji-pu Ma

We derive entropic Bell inequalities from considering entropy Venn diagrams. These entropic inequalities, akin to the Braunstein-Caves inequalities, are violated for a quantum mechanical Einstein-Podolsky-Rosen pair, which implies that the…

Quantum Physics · Physics 2009-10-30 N. J. Cerf , C. Adami

Bell-type inequalities and violations thereof reveal the fundamental differences between standard probability theory and its quantum counterpart. In the course of previous investigations ultimate bounds on quantum mechanical violations have…

Quantum Physics · Physics 2007-05-23 Stefan Filipp , Karl Svozil

Tight Bell inequalities are facets of Pitowsky's correlation polytope and are usually obtained from its extreme points by solving the hull problem. Here we present an alternative method based on a combination of algebraic results on…

Quantum Physics · Physics 2015-06-03 Costantino Budroni , Adan Cabello

Quantum computational experiments exploiting Noisy Intermediate-Scale Quantum (NISQ) devices to demonstrate violation of a Bell inequality are proposed. They consist of running specified quantum algorithms on few-qubit computers. If such a…

Quantum Physics · Physics 2020-09-02 H. W. L. Naus , H. Polinder

We derive a single general Bell inequality which is a necessary and sufficient condition for the correlation function for N particles to be describable in a local and realistic picture, for the case in which measurements on each particle…

Quantum Physics · Physics 2009-11-07 Marek Zukowski , Caslav Brukner

Violations of Bell inequalities in classical optics have been demonstrated in terms of field mean intensities and correlations, however, the quantum meaning of violations point to statistics and probabilities. We present a violation of Bell…

Quantum Physics · Physics 2023-01-31 Laura Ares , Alfredo Luis

We show that the "practical" Bell inequalities, which use intensities as the observed variables, commonly used in quantum optics and widely accepted in the community, suffer from an inherent loophole, which severely limits the range of…

Quantum Physics · Physics 2016-10-07 Marek Zukowski , Marcin Wiesniak , Wieslaw Laskowski

Bell's theorem for systems more complicated than two qubits faces a hidden, as yet undiscussed, problem. One of the methods to derive Bell's inequalities is to assume existence of joint probability distribution for measurement results for…

Quantum Physics · Physics 2012-09-24 Arijit Dutta , Marcin Wieśniak , Marek Żukowski

Bell's inequalities, in the form given by Cerf and Adami, are derived from the combination of the second law of thermodynamics and the Markov postulate. Violations of these inequalities are discussed in terms of the mixing characteristics…

Quantum Physics · Physics 2007-05-23 Ian T. Durham

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.…

The structure of Bell-type inequalities detecting genuine multipartite non-locality, and hence detecting genuine multipartite entanglement, is investigated. We first present a simple and intuitive approach to Svetlichny's original…

Quantum Physics · Physics 2014-10-20 Jean-Daniel Bancal , Nicolas Brunner , Nicolas Gisin , Yeong-Cherng Liang

According to recent reports, the last loopholes in testing Bell's inequality are closed. It is argued that the really important task in this field has not been tackled yet and that the leading experiments claiming to close locality and…

Quantum Physics · Physics 2007-05-23 L. Vaidman

For a class of mixed two -qubit states we show that it is not possible to discriminate between states violating or non - violating Bell - CHSH inequalities, knowing only their entanglement and mixedness. For a large set of possible values…

Quantum Physics · Physics 2009-11-10 L. Derkacz , L. Jakobczyk

We propose a whole family of physical states that yield a violation of the Bell CHSH inequality arbitrarily close to its maximum value, when using quadrature phase homodyne detection. This result is based on a new binning process called…

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

The number of steps required in order to maximize a Bell inequality for arbitrary number of qubits is shown to grow exponentially with either the number of steps and the number of parties involved. The proof that the optimization of such…

Quantum Physics · Physics 2015-03-03 J. Batle , C. H. Raymond Ooi