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Related papers: Quantum smoothing

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This survey gives a comprehensive account of quantum correlations understood as a phenomenon stemming from the rules of quantization. Centered on quantum probability it describes the physical concepts related to correlations (both classical…

Quantum Physics · Physics 2015-05-22 W. A. Majewski

In this paper, we present a thought experiment that demonstrates that the equivalence of quantum reduced states and statistical mixed states of ensembles is not merely a simple mathematical formulation in quantum mechanics, but rather…

Quantum Physics · Physics 2025-04-18 Zhihong Zuo

Quantum Theory is one of the pillars of modern science developed over the last hundred years. In this review paper we introduce, step by step, the quantum theory understood as a mathematical model describing quantum experiments. We start…

Quantum Physics · Physics 2015-05-13 Teiko Heinosaari , Mario Ziman

Quantum entanglement is at the heart of many tasks in quantum information. Apart from simple cases (low dimensions, few particles, pure states), however, the mathematical structure of entanglement is not yet fully understood. This tutorial…

Quantum Physics · Physics 2015-06-26 Dagmar Bruss

Amount of entanglement carried by a quantum bipartite state is usually evaluated in terms of concurrence (see Ref. 1). We give a physical interpretation of concurrence that reveals a way of its direct measurement and discuss possible…

Quantum Physics · Physics 2016-08-16 Alexander Klyachko , Barış Öztop , Alexander S. Shumovsky

We propose a new measure of quantum entanglement. Our measure is defined in terms of conditional information transmission for a Quantum Bayesian Net. We show that our measure is identically equal to the Entanglement of Formation in the case…

Quantum Physics · Physics 2007-05-23 Robert R. Tucci

We present a concise introduction to quantum entanglement. Concentrating on bipartite systems we review the separability criteria and measures of entanglement. We focus our attention on geometry of the sets of separable and maximally…

Quantum Physics · Physics 2007-05-23 Karol Zyczkowski , Ingemar Bengtsson

Tracking the dynamics of a quantum system is conventionally achieved by monitoring the system continuously in time and filtering the information contained in measurement records via the causal quantum trajectory approach. However, in…

The frame of classical probability theory can be generalized by enlarging the usual family of random variables in order to encompass nondeterministic ones: this leads to a frame in which two kinds of correlations emerge: the classical…

Quantum Physics · Physics 2007-05-23 E. G. Beltrametti , S. Bugajski

Quantum metrology holds the promise of an early practical application of quantum technologies, in which measurements of physical quantities can be made with much greater precision than what is achievable with classical technologies. In this…

Quantum Physics · Physics 2021-01-27 Jasminder S. Sidhu , Pieter Kok

Interaction with environment may lead to the transition of quantum system from pure state to the mixed one. In this case, the problem of definition of entanglement may arise. In particular, quantitative measure of entanglement concurrence…

Quantum Physics · Physics 2008-09-16 Levan Chotorlishvili

We study entanglement-assisted quantum and classical communication over a single use of a quantum channel, which itself can correspond to a finite number of uses of a channel with arbitrarily correlated noise. We obtain characterizations of…

Quantum Physics · Physics 2013-06-20 Nilanjana Datta , Min-Hsiu Hsieh

Quantum entanglement is a unique correlation phenomenon in quantum mechanics, and the measurement of quantum entanglement plays an important role in quantum computing and quantum communication. Many mainstream entanglement criteria and…

Quantum Physics · Physics 2024-11-12 Hao-Nan Qiang , Jing-Ling Chen

Smoothing is a technique that estimates the state of a system using measurement information both prior and posterior to the estimation time. Two notable examples of this technique are the Rauch-Tung-Striebel and Mayne-Fraser-Potter…

Quantum Physics · Physics 2021-09-24 Kiarn T. Laverick

Unlike the classical smoothing theory, it is well known that quantum smoothers are, in general, not well--defined by the quantum conditional expectation. The purpose of this paper is to propose a new quantum smoothing theory based on the…

Quantum Physics · Physics 2021-12-28 Kentaro Ohki

We consider a quantum state shared between many distant locations, and define a quantum information processing primitive, state merging, that optimally merges the state into one location. As announced in [Horodecki, Oppenheim, Winter,…

Quantum Physics · Physics 2008-06-12 Michal Horodecki , Jonathan Oppenheim , Andreas Winter

Quantifying unknown quantum entanglement experimentally is a difficult task, but also becomes more and more necessary because of the fast development of quantum engineering. Machine learning provides practical solutions to this fundamental…

Quantum Physics · Physics 2023-06-21 Xiaodie Lin , Zhenyu Chen , Zhaohui Wei

Quantum annealing is a generic algorithm using quantum-mechanical fluctuations to search for the solution of an optimization problem. The present paper first reviews the fundamentals of quantum annealing and then reports on preliminary…

Disordered Systems and Neural Networks · Physics 2010-06-10 Masayuki Ohzeki , Hidetoshi Nishimori

Quantum entanglement is usually revealed via a well aligned, carefully chosen set of measurements. Yet, under a number of experimental conditions, for example in communication within multiparty quantum networks, noise along the channels or…

In the discussion about the quantumness of NMR computation a conclusion is done that computational states are separable and therefore can not be entangled. This conclusion is based on the assumption that the initial density matrix of an…

Quantum Physics · Physics 2007-05-23 Alexander R. Kessel , Vladimir L. Ermakov