Chaos, Regularity, and Noise in Self-Gravitating Systems
Abstract
Description
This paper summarises a number of new, potentially significant, results, obtained recently by the author and his collaborators, which impact on various issues related to the gravitational N-body problem, both Newtonianly and in the context of general relativity. Topics addressed include: (1) direct N-body simulations and their interpretation, with reference to the observed exponential instability towards small changes in initial conditions and the phenomenon of ``nonviolent relaxation;'' (2) the Hamiltonian structure of the collisionless Boltzmann equation of general relativity, i.e., the Vlasov-Einstein system; (3) ``transient ensemble dynamics,'' i.e.,,the short time statistical characterisation of collections of orbits in nonintegrable mean field potentials; and (4) the structural stability of the smooth potential approximation typically used in galactic dynamics.
19 pages, LaTeX, Invited plenary talk at the Seventh Marcel Grossmann Meeting July 1994
19 pages, LaTeX, Invited plenary talk at the Seventh Marcel Grossmann Meeting July 1994