RELATIVE CHAOS IN GRAVITATING SYSTEMS WITH MASSIVE CENTER

A geometric method, namely the Ricci curvature criterion, is used to s tudy the relative instability of evolving N-body gravitating systems w ith massive centres. The performed numerical experiments show that the Ricci curvature decreases with the increase in central concentration, thus indicating an increasing instability for systems with massive ce ntre - either in the form of a point mass or a core formed during the evolution of single and multimass systems. Simulations of such systems do indeed suggest that they have faster gravothermal evolution than l ess concentrated ones. (C) 1998 Elsevier Science B.V.