2001/01/30 by Jochen Gemmer, A. F. Otte, Alexander Otte +2 · 1 citation
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Quantum Mechanics and Applications #Statistical Mechanics and Entropy #quant-ph
paper · pdf · doi:10.1103/physrevlett.86.1927
4 pages. Accepted for publication in Phys. Rev. Lett
arxiv created 2001/01/30 · openalex publication_date 2001/03/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We reinterpret the microcanonical conditions in the quantum domain as constraints for the interaction of the "gas subsystem" under consideration and its environment ("container"). The time average of a purity measure is found to equal the average over the respective path in Hilbert space. We then show that for typical (degenerate or nondegenerate) thermodynamical systems almost all states within the allowed region of Hilbert space have a local von Neumann entropy S close to the maximum and a purity P close to its minimum, respectively. Typically, thermodynamical systems should obey the second law.