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Updated: May 24, 2026
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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Entropy production and equilibration in Yang-Mills quantum mechanics
Hung-Ming Tsai1, Berndt Müller
1Department of Physics, Duke University, Durham, North Carolina 27708, USA.
Summary
We developed a method to track quantum system entropy using the Husimi distribution. This approach shows coarse-grained entropy saturates to microcanonical entropy for isolated systems.
Area of Science:
- Quantum mechanics
- Statistical mechanics
- Quantum information theory
Background:
- The Husimi distribution offers a coarse-grained view of quantum system phase-space distributions.
- It is a valuable tool for analyzing the evolution of system entropy.
- Understanding entropy growth is crucial for characterizing quantum systems.
Purpose of the Study:
- To present a general method for solving the Husimi equation of motion for isolated quantum systems.
- To construct a conserved coarse-grained Hamiltonian.
- To numerically investigate the entropy evolution in a specific quantum system.
Main Methods:
- Developing a systematic approach to solve the Husimi equation.
- Constructing a coarse-grained Hamiltonian with a conserved expectation value.
- Numerical simulation of the Husimi equation for 2D Yang-Mills quantum mechanics (x-y model).
Main Results:
- The proposed method successfully solves the Husimi equation for isolated systems.
- The coarse-grained entropy of a highly excited state in the x-y model was calculated.
- The study demonstrates that coarse-grained entropy saturates to the microcanonical entropy.
Conclusions:
- The developed method provides a robust way to study entropy in quantum systems.
- The saturation of coarse-grained entropy to microcanonical entropy is confirmed numerically.
- This work offers insights into the statistical properties of quantum systems.
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