English
Related papers

Related papers: Statistics and Nos\'e formalism for Ehrenfest dyna…

200 papers

The Ehrenfest theorem and the Robertson uncertainty relation are well-known basic equations in quantum mechanics. However, there exist problematic cases, where the Ehrenfest theorem and the Robertson uncertainty relation are not correct.…

Quantum Physics · Physics 2019-09-24 Klaus Renziehausen , Ingo Barth

Mixed quantum-classical methods, such as surface hopping and Ehrenfest dynamics, have proven useful for describing molecular processes involving multiple electronic states. These methods require propagating many independent trajectories,…

Chemical Physics · Physics 2025-08-15 Alan Scheidegger , Jiří J. L. Vaníček

On the basis of the non-commutative q-calculus, we investigate a q-deformation of the classical Poisson bracket in order to formulate a generalized q-deformed dynamics in the classical regime. The obtained q-deformed Poisson bracket appears…

Quantum Physics · Physics 2009-01-07 A. Lavagno , A. M. Scarfone , P. Narayana Swamy

Stochastic evolution underpins several approaches to the dynamics of open quantum systems, such as random modulation of Hamiltonian parameters, the stochastic Schrodinger equation (SSE), and the stochastic Liouville equation (SLE). These…

Quantum Physics · Physics 2026-01-22 Pietro De Checchi , Federico Gallina , Barbara Fresch , Giulio G. Giusteri

Quantum Field Theory (QFT) makes predictions by combining two sets of assumptions: (1) quantum dynamics, such as a Schrodinger or Liouville equation; (2) quantum measurement, such as stochastic collapse to an eigenfunction of a measurement…

Quantum Physics · Physics 2007-05-23 Paul J. Werbos , Ludmila Dolmatova Werbos

Imagine a freely rotating rigid body. The body has three principal axes of rotation. It follows from mathematical analysis of the evolution equations that pure rotations around the major and minor axes are stable while rotation around the…

Computational Physics · Physics 2019-08-27 Michal Pavelka , Vaclav Klika , Miroslav Grmela

A recent proposal for mixed dynamics of classical and quantum ensembles is shown, in contrast to other proposals, to satisfy the minimal algebraic requirements proposed by Salcedo for any consistent formulation of such dynamics. Generalised…

Quantum Physics · Physics 2008-10-09 Michael J. W. Hall

Einstein conjectured long ago that much of quantum mechanics might be derived as a statistical formalism describing the dynamics of classical systems. Bell's Theorem experiments have ruled out complete equivalence between quantum field…

Quantum Physics · Physics 2007-05-23 Paul J. Werbos

We consider an Ehrenfest approximation for a particle in a double-well potential in the presence of an external environment schematized as a finite resource heat bath. This allows us to explore how the limitations in the applicability of…

Quantum Physics · Physics 2015-10-09 Stephen Choi , Roberto Onofrio , Bala Sundaram

We apply a variant of the Nose-Hoover thermostat to derive the Hamiltonian of a nonextensive system that is compatible with the canonical ensemble of the generalized thermostatistics of Tsallis. This microdynamical approach provides a…

Statistical Mechanics · Physics 2009-11-07 J. S. Andrade , M. P. Almeida , A. A. Moreira , G. A. Farias

Hamilton variational principle for special type of statistical ensemble of deterministic dynamical systems is derived. Thie form of variational principle allows one to describe the statistical ensemble in terms of wave functions and…

Mathematical Physics · Physics 2007-05-23 Yuri A. Rylov

We consider a coupled system of Schr\"odinger equations, arising in quantum mechanics via the so-called time-dependent self-consistent field method. Using Wigner transformation techniques we study the corresponding classical limit dynamics…

Analysis of PDEs · Mathematics 2014-06-17 Shi Jin , Christof Sparber , Zhennan Zhou

The two-dimensional electron-nuclear Schr\"odinger equation using soft-core Coulomb potentials has been a cornerstone for modeling and predicting the behavior of one-active-electron diatomic molecules, particularly for processes where both…

Chemical Physics · Physics 2020-07-01 Bo Y. Chang , Seokmin Shin , Vladimir S. Malinovsky , Ignacio R. Sola

We have developed a method for complementing an arbitrary classical dynamical system to a quantum system using the Lorenz and R\"ossler systems as examples. The Schr\"odinger equation for the corresponding quantum statistical ensemble is…

Chaotic Dynamics · Physics 2014-12-30 Yu. I. Bogdanov , N. A. Bogdanova

In closed quantum systems, wavepackets can spread exponentially in time due to chaos, forming long-range superpositions in just seconds for ordinary macroscopic systems. A weakly coupled environment is conjectured to decohere the system and…

Quantum Physics · Physics 2025-05-20 Felipe Hernández , Daniel Ranard , C. Jess Riedel

We study the classical mechanics and dynamics of particles that retains some memory of quantum statistics. Our work builds on earlier work on the statistical mechanics and thermodynamics of such particles. Starting from the effective…

Quantum Physics · Physics 2025-11-21 Varsha Subramanyan , T. H. Hansson , Smitha Vishveshwara

We investigate detailed balance for a quantum system interacting with thermal radiation within mixed quantum-classical theory. For a two-level system coupled to classical radiation fields, three semiclassical methods are benchmarked: (1)…

Chemical Physics · Physics 2019-07-17 Hsing-Ta Chen , Tao E. Li , Abraham Nitzan , Joseph E. Subotnik

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

Relaxation dynamics of complex quantum systems with strong interactions towards the steady state is a fundamental problem in statistical mechanics. The steady state of subsystems weakly interacting with their environment is described by the…

Statistical Mechanics · Physics 2016-06-22 Alexey M. Shakirov , Yulia E. Shchadilova , Alexey N. Rubtsov

Due to the exponential growth of the state space of coupled quantum systems it is not possible, in general, to numerically store the state of a very large number of quantum systems within a classical computer. We demonstrate a method for…

Quantum Physics · Physics 2017-02-07 J. J. Bowen , V. M. Dwyer , I. W. Phillips , M. J. Everitt