Related Experiment Video
Updated: May 11, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Generic features of the dynamics of complex open quantum systems: statistical approach based on averages over the
Manuel Gessner1, Heinz-Peter Breuer
1Physikalisches Institut, Universität Freiburg, Hermann-Herder-Strasse 3, D-79104 Freiburg, Germany. manuel.gessner@physik.uni-freiburg.de
Abstract:
We obtain exact analytic expressions for a class of functions expressed as integrals over the Haar measure of the unitary group in d dimensions. Based on these general mathematical results, we investigate generic dynamical properties of complex open quantum systems, employing arguments from ensemble theory. We further generalize these results to arbitrary eigenvalue distributions, allowing a detailed comparison of typical regular and chaotic systems with the help of concepts from random matrix theory. To illustrate the physical relevance and the general applicability of our results we present a series of examples related to the fields of open quantum systems and nonequilibrium quantum thermodynamics. These include the effect of initial correlations, the average quantum dynamical maps, the generic dynamics of system-environment pure state entanglement and, finally, the equilibration of generic open and closed quantum systems.
Related Concept Videos
Dimensionless Groups in Fluid Mechanics
Reaction Mechanisms: The Steady-State Approximation
State Space Representation
Consider an RLC circuit, a...
Complexation Equilibria: Overview
The equilibrium constant of the complexation reaction is represented as the formation constant...
First Law: Particles in One-dimensional Equilibrium
Free Energy Changes for Nonstandard States
