2005/09/26 by Atsushi Taruya, Masa-aki Sakagami, M. Sakagami · 1 citation
Economics, Econometrics and Finance · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Complex Systems and Time Series Analysis #Statistical Mechanics and Entropy #astro-ph #cond-mat.stat-mech #gr-qc
paper · pdf · doi:10.1111/j.1365-2966.2005.09635.x
published as Mon.Not.Roy.Astron.Soc.364:990-1010,2005 · 26 pages, 26 figures, accepted for publication in MNRAS
arxiv created 2005/09/26 · openalex publication_date 2005/11/07 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this paper, a quantitative characterization of the evolutionary sequence of a stellar self-gravitating system is investigated, focusing on the pre-collapse stage of the long-term dynamical evolution. In particular, we consider the quasi-equilibrium behaviour of N-body systems in the setup of the so-called Antonov problem, i.e. a self-gravitating N-body system confined within an adiabatic wall, and try to seek a possible connection with the thermostatistics of self-gravitating systems. For this purpose, a series of long-term N-body simulations with various initial conditions are performed. We found that a quasi-equilibrium sequence away from thermal equilibrium can be characterized by a one-parameter family of stellar models. Especially, a stellar polytropic distribution satisfying the effective equation of state P∝ρ1+1/n provides an excellent approximation to the evolutionary sequence of the N-body system. Based on the numerical results, we discuss the link between the quasi-equilibrium state and the generalized thermostatistics by means of the non-extensive entropy.