Statistical mechanics of violent relaxation in stellar systems
| dc.creator | Chavanis, P. H. | |
| dc.date | 2002-12-09 | |
| dc.date.accessioned | 2026-07-07T02:06:47Z | |
| dc.date.available | 2026-07-07T02:06:47Z | |
| dc.description | We discuss the statistical mechanics of violent relaxation in stellar systems following the pioneering work of Lynden-Bell (1967). The solutions of the gravitational Vlasov-Poisson system develop finer and finer filaments so that a statistical description is appropriate to smooth out the small-scales and describe the ``coarse-grained'' dynamics. In a coarse-grained sense, the system is expected to reach an equilibrium state of a Fermi-Dirac type within a few dynamical times. We describe in detail the equilibrium phase diagram and the nature of phase transitions which occur in self-gravitating systems. Then, we introduce a small-scale parametrization of the Vlasov equation and propose a set of relaxation equations for the coarse-grained dynamics. These relaxation equations, of a generalized Fokker-Planck type, are derived from a Maximum Entropy Production Principle (MEPP). We make a link with the quasilinear theory of the Vlasov-Poisson system and derive a truncated model appropriate to collisionless systems subject to tidal forces. With the aid of this kinetic theory, we qualitatively discuss the concept of ``incomplete relaxation'' and the limitations of Lynden-Bell's theory. | |
| dc.description | In Proceedings of the Conference on Multiscale Problems in Science and Technology, edited by N. Antonic, C.J. van Duijn, W. Jager, and A. Mikelic (Springer, Berlin, 2002) | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0212205 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0212205 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/5484 | |
| dc.subject | Astrophysics | |
| dc.title | Statistical mechanics of violent relaxation in stellar systems | |
| dc.type | text |