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Related papers: Quantum smoothing for classical mixtures

200 papers

We review recent research on the transport properties of classical waves through chaotic systems with special emphasis on microwaves and sound waves. Inasmuch as these experiments use antennas or transducers to couple waves into or out of…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 U. Kuhl , H. -J. Stoeckmann , R. Weaver

Quantum state smoothing is a technique for assigning a valid quantum state to a partially observed dynamical system, using measurement records both prior and posterior to an estimation time. We show that the technique is greatly simplified…

Quantum Physics · Physics 2025-09-09 Kiarn T. Laverick , Areeya Chantasri , Howard M. Wiseman

We attempt to contribute some novel points of view to the "foundations of quantum mechanics", using mathematical tools from "quantum probability theory" (such as the theory of operator algebras). We first introduce an abstract algebraic…

Quantum Physics · Physics 2013-10-08 J. Fröhlich , B. Schubnel

What fundamental constraints characterize the relationship between a mixture $\rho = \sum_i p_i \rho_i$ of quantum states, the states $\rho_i$ being mixed, and the probabilities $p_i$? What fundamental constraints characterize the…

Quantum Physics · Physics 2009-11-06 M. A. Nielsen

Familiar formulations of classical and quantum mechanics are shown to follow from a general theory of mechanics based on pure states with an intrinsic probability structure. This theory is developed to the stage where theorems from quantum…

Quantum Physics · Physics 2018-06-26 Peter Taylor

A ubiquitous feature of quantum mechanical theories is the existence of states of superposition. This is expected to be no different for a quantum gravity theory. Guided by this consideration and others we consider a framework in which…

Quantum Physics · Physics 2023-12-22 Elliott Tammaro , Hunter Angle , Edmund Mbadu

Quantum-classical correspondence for the average shape of eigenfunctions and the local spectral density of states are well-known facts. In this paper, the fluctuations that quantum mechanical wave functions present around the classical…

Chaotic Dynamics · Physics 2008-11-26 L. Benet , J. Flores , H. Hernandez-Saldaña , F. M. Izrailev , F. Leyvraz , T. H. Seligman

What is the quantum state of the universe? Although there have been several interesting suggestions, the question remains open. In this paper, I consider a natural choice for the universal quantum state arising from the Past Hypothesis, a…

Quantum Physics · Physics 2019-01-25 Eddy Keming Chen

Measurement is one of the key concepts which discriminates classical and quantum physics. Unlike classical systems, a measurement on a quantum system typically alters it drastically as a result of wave function collapse. Here we suggest…

Quantum Physics · Physics 2018-07-18 Abolfazl Bayat , Bedoor Alkurtass , Pasquale Sodano , Henrik Johannesson , Sougato Bose

We generalize classical statistical mechanics to describe the kinematics and the dynamics of systems whose variables are constrained by a single quantum postulate (discreteness of the spectrum of values of at least one variable of the…

Quantum Physics · Physics 2009-10-31 Marcello Cini

We present a new interpretation of the terms superposition, entanglement, and measurement that appear in quantum mechanics. We hypothesize that the structure of the wave function for a quantum system at the sub-Planck scale has a…

Quantum Physics · Physics 2009-08-10 Rajendra K Bera , Vikram Menon

We define the model of quantum circuits with density matrices, where non-unitary gates are allowed. Measurements in the middle of the computation, noise and decoherence are implemented in a natural way in this model, which is shown to be…

Quantum Physics · Physics 2007-05-23 Dorit Aharonov , Alexei Kitaev , Noam Nisan

A motivation is given for expressing classical mechanics in terms of diagonal projection matrices and diagonal density matrices. Then quantum mechanics is seen to be a simple generalization in which one replaces the diagonal real matrices…

Quantum Physics · Physics 2009-11-05 Don N. Page

This paper presents a hybrid classical-quantum program for density estimation and supervised classification. The program is implemented as a quantum circuit in a high-dimensional quantum computer simulator. We show that the proposed quantum…

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

I provide a simple derivation of the Born rule as giving a classical probability, that is, the ratio of the measure of favorable states of the system to the measure of its total possible states. In classical systems, the probability is due…

Quantum Physics · Physics 2025-04-29 Ovidiu Cristinel Stoica

The choice of mathematical representation when describing physical systems is of great consequence, and this choice is usually determined by the properties of the problem at hand. Here we examine the little-known wave operator…

Quantum Physics · Physics 2024-01-26 Gerard McCaul , Dmitry V. Zhdanov , Denys I. Bondar

The probability representation of states in standard quantum mechanics where the quantum states are associated with fair probability distributions (instead of wave function or density matrix) is shortly commented and bibliography related to…

Quantum Physics · Physics 2007-05-23 V. I. Man'ko , O. V. Pilyavets , V. G. Zborovskii

One of the crucial differences between mathematical models of classical and quantum mechanics is the use of the tensor product of the state spaces of subsystems as the state space of the corresponding composite system. (To describe an…

General Physics · Physics 2010-08-03 Andrei Khrennikov

In classical stochastic theory, the joint probability distributions of a stochastic process obey by definition the Kolmogorov consistency conditions. Interpreting such a process as a sequence of physical measurements with probabilistic…

Quantum Physics · Physics 2023-12-12 Moritz F. Richter , Andrea Smirne , Walter T. Strunz , Dario Egloff