Computer simulations of rotating systems of few particles bound by gravitation

Abstract

The shapes of rotating drops of liquid bound by gravitation is a classical subject of study. Inspired by this classical theory, we have simulated numerically a related problem, the rotating rigid configurations of a finite number of point particles. Two particles at a distance [Formula: see text] have a long range attractive potential [Formula: see text] and a short range repulsive potential [Formula: see text] preventing collapse. We take the angular momentum to be conserved, but not the energy.This system has a variable density, unlike the classical liquid drops. When the number of particles is small, it is more rigid than a liquid drop, implying that many different stable equilibrium configurations may exist with the same angular momentum but different energies. When the number of particles becomes large, our system should resemble a self-gravitating polytropic gas.We present here the results of a preliminary study with only 3, 4, and 5 particles. The methods used could be applied to the study of rotating molecules.