Gravitational Thermodynamics

Abstract

The gravitational N-body problem, for $N>2$, is the oldest unsolved problem in mathematical physics. Some of the most ideal examples that can be found in nature are globular star clusters, with $N\sim 10^6$. In this overview, I discuss six types of fundamental sources of unpredictability, each of which poses a different challenge to attempts to determine the long-term behavior of these systems, governed by a peculiar type of thermodynamics.

19 pages, 5 included figures, Tex, uses psfig.tex. To appear in `Complexity', as part of the Proceedings of the Workshop on Fundamental Sources of Unpredictability, held at the Santa Fe Institute, March 28-30, 1996, eds. James Hartle, Piet Hut, and Joseph Traub