2006/11/02 by Marco Frasca
Mathematics · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Quantum many-body systems #Statistical Mechanics and Entropy #cond-mat.other #math-ph #math.MP #quant-ph
paper · pdf · doi:10.1088/1742-6596/67/1/012026
published as Journal of Physics: Conference Series 67 (2007) 012026 · 5 pages, no figures. Contribution to proceedings of DICE 2006 (Piombino, Italy, September 11-15, 2006)
arxiv created 2006/11/02 · openalex publication_date 2007/05/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
Time evolution operator in quantum mechanics can be changed into a statistical operator by a Wick rotation. This strict relation between statistical mechanics and quantum evolution can reveal deep results when the thermodynamic limit is considered. These results translate in a set of theorems proving that these effects can be effectively at work producing an emerging classical world without recurring to any external entity that in some cases cannot be properly defined. For a many-body system it has been recently shown that Gaussian decay of the coherence is the rule with a duration of recurrence more and more small as the number of particles increases. This effect has been observed experimentally. More generally, a theorem about coherence of bulk matter can be proved. All this takes us to the conclusion that a well defined boundary for the quantum to classical world does exist and that can be drawn by the thermodynamic limit, extending in this way the deep link between statistical mechanics and quantum evolution to a high degree.