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Related papers: Quantum dynamics as a pseudo-density matrix

200 papers

This paper aims at presenting a few models of quantum dynamics whose description involves the analysis of random unitary matrices for which dynamical localization has been proven to hold. Some models come from physical approximations…

Mathematical Physics · Physics 2011-05-03 Alain Joye

The Hermiticity condition in quantum mechanics required for the characterisation of (a) physical observables and (b) generators of unitary motions can be relaxed into a wider class of operators whose eigenvalues are real and whose…

Quantum Physics · Physics 2015-06-16 Dorje C. Brody

Non-relativistic quantum theory is derived from information codified into an appropriate statistical model. The basic assumption is that there is an irreducible uncertainty in the location of particles: positions constitute a configuration…

Quantum Physics · Physics 2015-05-13 Ariel Caticha

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

In usual quantum theory, the information available about a quantum system is defined in terms of the density matrix describing it on a spacelike surface. This definition must be generalized for extensions of quantum theory which do not have…

General Relativity and Quantum Cosmology · Physics 2009-10-22 James B. Hartle

In the geometry of quantum-mechanical processes, the time-varying curvature coefficient of a quantum evolution is specified by the magnitude squared of the covariant derivative of the tangent vector to the state vector. In particular, the…

Quantum Physics · Physics 2025-01-07 Carlo Cafaro , Leonardo Rossetti , Paul M. Alsing

The meaning of statistical experiments with single microsystems in quantum mechanics is discussed and a general model in the framework of non-relativistic quantum field theory is proposed, to describe both coherent and incoherent…

Quantum Physics · Physics 2009-10-30 L. Lanz , B. Vacchini

We present a theory for the dynamical evolution of a quantum system coupled to a complex many-body intrinsic system/environment. By modelling the intrinsic many-body system with parametric random matrices, we study the types of effective…

Nuclear Theory · Physics 2009-10-30 Aurel Bulgac , Gui DoDang , Dimitri Kusnezov

We study the dynamics of a particle in continuous time and space, the displacement of which is governed by an internal degree of freedom (spin). In one definite limit, the so-called quantum random walk is recovered but, although quite…

Quantum Physics · Physics 2009-11-10 Claude Aslangul

We show that the discrete-time evolution of an open quantum system generated by a single quantum channel $T$ can be embedded in the discrete-time evolution of an enlarged closed quantum system, i.e. we construct a unitary dilation of the…

Mathematical Physics · Physics 2020-08-17 Frederik vom Ende , Gunther Dirr

We analyze classical and quantum dynamics of a particle in 2d spacetimes with constant curvature which are locally isometric but globally different. We show that global symmetries of spacetime specify the symmetries of physical phase-space…

General Relativity and Quantum Cosmology · Physics 2009-10-31 George Jorjadze , Włodzimierz Piechocki

We study the emergence over time of a universal, uniform distribution of quantum states supported on a finite subsystem, induced by projectively measuring the rest of the system. Dubbed deep thermalization, this phenomenon represents a form…

Quantum Physics · Physics 2023-01-04 Matteo Ippoliti , Wen Wei Ho

By modelling quantum systems as emerging from a (classical) sub-quantum thermodynamics, the quantum mechanical "decay of the wave packet" is shown to simply result from sub-quantum diffusion with a specific diffusion coefficient varying in…

General Physics · Physics 2011-08-30 Gerhard Groessing , Siegfried Fussy , Johannes Mesa Pascasio , Herbert Schwabl

In previous work we discussed the quantization of paths in spacetime. Building on these ideas we have developed a mathematically coherent theory addressing a number of open questions concerning Loop Quantum Gravity. Our approach develops a…

General Relativity and Quantum Cosmology · Physics 2019-02-07 James Moffat , Charles H. -T. Wang

As time passes, once simple quantum states tend to become more complex. For strongly coupled k-local Hamiltonians, this growth of computational complexity has been conjectured to follow a distinctive and universal pattern. In this paper we…

High Energy Physics - Theory · Physics 2017-02-28 Adam R. Brown , Leonard Susskind , Ying Zhao

We propose an energy-driven stochastic master equation for the density matrix as a dynamical model for quantum state reduction. In contrast, most previous studies of state reduction have considered stochastic extensions of the Schr\"odinger…

Quantum Physics · Physics 2016-12-30 Dorje C. Brody , Lane P. Hughston

Quantum Darwinism extends the traditional formalism of decoherence to explain the emergence of classicality in a quantum universe. A classical description emerges when the environment tends to redundantly acquire information about the…

Quantum Physics · Physics 2020-04-09 Graeme Pleasance , Barry M. Garraway

We study thermalization in a one-dimensional quantum system consisting of a noninteracting fermionic chain with each site of the chain coupled to an additional bath site. Using a density matrix renormalization group algorithm we investigate…

Statistical Mechanics · Physics 2013-03-14 N. Sedlmayr , J. Ren , F. Gebhard , J. Sirker

In a differential approach elaborated, we study the evolution of the parameters of Gaussian, mixed, continuous variable density matrices, whose dynamics are given by Hermitian Hamiltonians expressed as quadratic forms of the position and…

Quantum Physics · Physics 2020-05-26 Julio A. López-Saldívar , Margarita A. Man'ko , Vladimir I. Man'ko

Entanglement is a quantum resource, in some ways analogous to randomness in classical computation. Inspired by recent work of Gheorghiu and Hoban, we define the notion of "pseudoentanglement'', a property exhibited by ensembles of…