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Related papers: A CH-type Inequality For Real Experiments

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Quantum mechanics allows for coherent control over the order in which different processes take place on a target system, giving rise to a new feature known as indefinite causal order. Indefinite causal order provides a resource for quantum…

It is first shown that when the Schr\"{o}dinger equation for a wave function is written in the polar form, complete information about the system's {\em quantum-ness} is separated out in a single term $Q$, the so called `quantum potential'.…

Quantum Physics · Physics 2018-01-09 Partha Ghose

We explore quantum properties of a which-way detector using three versions of an idealized two slit arrangements. Firstly we derive complementarity relations for the detector; secondly we show how the "experiment" may be altered in such a…

Quantum Physics · Physics 2015-06-19 J. S. Oliveira Filho , R. Rossi , M. C. Nemes

In this paper, we suggest an alternative interpretation for the quantum state vector, which, by considering temporal parts for physical objects, aims to give an intelligible account of measurement problem in quantum mechanics. We examine…

History and Philosophy of Physics · Physics 2025-06-27 Alireza Mansouri , Mehdi Golshani , Amir Ehsan Karbasizadeh

Quantum telepathy is the phenomenon where two non-communicating parties can exhibit correlated behaviors that are impossible to achieve using classical resources. This is also known as Bell inequality violation and is made possible by…

Quantum Physics · Physics 2025-08-27 Dawei Ding , Liang Jiang

This note starts with a recapitulation of what people call the ``Measurement Problem'' of Quantum Mechanics (QM). The dissipative nature of the quantum-mechanical time-evolution of averages of states over large ensembles of identical…

Quantum Physics · Physics 2026-03-27 Jürg Fröhlich , Alessandro Pizzo

Quantum mechanics has many counter-intuitive consequences which contradict our intuition which is based on classical physics. Here we discuss a special aspect of quantum mechanics, namely the possibility of entanglement between two or more…

Quantum Physics · Physics 2009-10-31 Martin B. Plenio , Vlatko Vedral

Measurement incompatibility and quantum non-locality are two key features of quantum theory. Violations of Bell inequalities require quantum entanglement and incompatibility of the measurements used by the two parties involved in the…

Mathematical Physics · Physics 2023-03-30 Faedi Loulidi , Ion Nechita

In theory, quantum key distribution (QKD) offers unconditional security based on the laws of physics. However, as demonstrated in recent quantum hacking theory and experimental papers, detection efficiency loophole can be fatal to the…

Quantum Physics · Physics 2009-01-06 Chi-Hang Fred Fung , Kiyoshi Tamaki , Bing Qi , Hoi-Kwong Lo , Xiongfeng Ma

The quantum description of the microscopic world is incompatible with the classical description of the macroscopic world, both mathematically and conceptually. Nevertheless, it is generally accepted that classical mechanics emerges from…

Quantum Physics · Physics 2025-08-11 Miguel Gallego , Borivoje Dakić

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…

A reduction mechanism resulting directly from the basic principles of quantum mechanics is proposed, inseparably from decoherence. A rather consistent theory of this effect is given and the next problems it raises are indicated.

Quantum Physics · Physics 2007-05-23 Roland Omnes

The existence of incompatible measurements, i.e. measurements which cannot be performed simultaneously on a single copy of a quantum state, constitutes an important distinction between quantum mechanics and classical theories. While…

Quantum Physics · Physics 2022-06-22 Krzysztof Mordasewicz , Jędrzej Kaniewski

It is well-known that no local model - in theory - can simulate the outcome statistics of a Bell-type experiment as long as the detection efficiency is higher than a threshold value. For the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality…

Quantum Physics · Physics 2023-02-14 Shihan Sajeed , Nigar Sultana , Charles Ci Wen Lim , Vadim Makarov

The main goal of this paper is to show that if a real valued function defined on a groupoid satisfies a certain Levi--Civita-type functional equation, then it also fulfills a Cauchy--Schwarz-type functional inequality. In particular, if the…

Rings and Algebras · Mathematics 2024-02-14 Zsolt Páles , Mahmood Kamil Shihab

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

We present new generalizations of Cauchy-Schwarz (CS) inequalities to multiple vectors and use them to derive multi-operator quantum uncertainty relations and propose multi-operator squeezing.

Quantum Physics · Physics 2026-02-24 Samuel R. Hedemann

We present generic Bell inequalities for multipartite multi-dimensional systems. The inequalities that any local realistic theories must obey are violated by quantum mechanics for even-dimensional multipartite systems. A large set of…

Quantum Physics · Physics 2009-11-11 W. Son , Jinhyoung Lee , M. S. Kim

Since the experimental observation of the violation of the Bell-CHSH inequalities, much has been said about the non-local and contextual character of the underlying system. But the hypothesis from which Bell's inequalities are derived…

Quantum Physics · Physics 2021-07-09 Aldo F. G. Solis-Labastida , Melina Gastelum , Jorge G. Hirsch

This work is divided into two parts. The first examines recent proposals for "witnessing" quantum gravity via entanglement from the point of view of Bronstein's original objection to a quantization of gravity. Using techniques from open…

General Relativity and Quantum Cosmology · Physics 2023-11-17 Giorgio Torrieri