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Related papers: Classical and Quantum Parts of the Quantum Dynamic…

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We study a class of theories in which space-time is treated classically, while interacting with quantum fields. These circumvent various no-go theorems and the pathologies of semi-classical gravity, by being linear in the density matrix and…

High Energy Physics - Theory · Physics 2022-02-15 Jonathan Oppenheim , Zachary Weller-Davies

Just like decent classical difference-difference systems define symplectic maps on suitable phase spaces, their counterparts with properly ordered noncommutative entries come as Heisenberg equations of motion for corresponding quantum…

High Energy Physics - Theory · Physics 2007-05-23 L. D. Faddeev , A. Yu. Volkov

A formalism is developed for describing approximate classical behaviour in finite (but possibly large) quantum systems. This is done in terms of a structure common to classical and quantum mechanics, viz. a Poisson space with a transition…

Quantum Physics · Physics 2015-06-26 N. P. Landsman

We compute numerically the time evolution of simple semiclassical states describing homogeneous and isotropic spatial geometries in quantum-reduced loop gravity under a deparametrized formulation of the dynamics, in which a reference matter…

General Relativity and Quantum Cosmology · Physics 2026-04-02 Ilkka Mäkinen

We propose a system of equations to describe the interaction of a quasiclassical variable $X$ with a set of quantum variables $x$ that goes beyond the usual mean field approximation. The idea is to regard the quantum system as continuously…

Quantum Physics · Physics 2009-10-30 L. Diosi , J. J. Halliwell

Semiclassical techniques have proven to be a very powerful method to extract physical effects from different quantum theories. Therefore, it is expected that in the near future they will play a very prominent role in the context of quantum…

General Relativity and Quantum Cosmology · Physics 2014-12-17 David Brizuela

An ensemble of classical subsystems interacting with surrounding particles has been considered. In general case, a phase volume of the subsystems ensemble was shown to be a function of time. The evolutional equations of the ensemble are…

Statistical Mechanics · Physics 2015-06-24 S. R. Sharov

We investigate the classical limit of non-Hermitian quantum dynamics arising from a coherent state approximation, and show that the resulting classical phase space dynamics can be described by generalised "canonical" equations of motion,…

Quantum Physics · Physics 2010-02-08 Eva-Maria Graefe , Michael Hoening , Hans Juergen Korsch

We numerically analyze the dynamical generation of quantum entanglement in a system of 2 interacting particles, started in a coherent separable state, for decreasing values of $\hbar$. As $\hbar\to 0$ the entanglement entropy, computed at…

Quantum Physics · Physics 2015-05-30 Giulio Casati , Italo Guarneri , Jose Reslen

In this paper we study the Hilbert space structure underlying the Koopman-von Neumann (KvN) operatorial formulation of classical mechanics. KvN limited themselves to study the Hilbert space of zero-forms that are the square integrable…

Quantum Physics · Physics 2009-11-07 E. Deotto , E. Gozzi , D. Mauro

This paper introduces several new classes of mathematical structures that have close connections with physics and with the theory of dynamical systems. The most general of these structures, called indivisible stochastic processes,…

Quantum Physics · Physics 2026-02-09 Jacob A. Barandes

Classical electrodynamics is reformulated in terms of wave functions in the classical phase space of electrodynamics, following the Koopman-von Neumann-Sudarshan prescription for classical mechanics on Hilbert spaces {\em sans} the…

Quantum Physics · Physics 2014-11-25 A. K. Rajagopal , Partha Ghose

In this paper a formalism for studying the dynamics of quantum systems coupled to classical spin environments is reviewed. The theory is based on generalized antisymmetric brackets and naturally predicts open-path off-diagonal geometric…

Quantum Physics · Physics 2016-10-21 Alessandro Sergi

Algorithmic approach is based on the assumption that any quantum evolution of many particle system can be simulated on a classical computer with the polynomial time and memory cost. Algorithms play the central role here but not the…

Quantum Physics · Physics 2007-05-23 Yuri Ozhigov

The measuring process is an external intervention in the dynamics of a quantum system. It involves a unitary interaction of that system with a measuring apparatus, a further interaction of both with an unknown environment causing…

Quantum Physics · Physics 2009-10-31 Asher Peres

We discuss the classical and quantum mechanical evolution of systems described by a Hamiltonian that is a function of a solvable one, both classically and quantum mechanically. The case in which the solvable Hamiltonian corresponds to the…

Quantum Physics · Physics 2015-05-13 J. Fernando Barbero G. , Iñaki Garay , Eduardo J. S. Villaseñor

We consider quantum systems which interact strongly with a rapidly varying environment and derive a Schrodinger-like equation which describes the time evolution of the average wave function. We show that the corresponding Hamiltonian can be…

General Physics · Physics 2009-11-07 R. Huerta , J. Wudka

The evolution of a quantum system interacting with an environment can be described as a unitary process acting on both the system and the environment. In this framework, the system's evolution can be predicted by tracing out the…

An extended variational principle providing the equations of motion for a system consisting of interacting classical, quasiclassical and quantum components is presented, and applied to the model of bilinear coupling. The relevant dynamical…

Quantum Physics · Physics 2009-11-13 M. Grigorescu

Classically, one could imagine a completely static space, thus without time. As is known, this picture is unconceivable in quantum physics due to vacuum fluctuations. The fundamental difference between the two frameworks is that classical…

High Energy Physics - Theory · Physics 2019-10-31 Roberto Longo