Hierarchical Methods for the N-Body Problem

The n-body problem is the problem of predicting the individual motions of a group of celestial objects interacting with each other gravitationally. It has been motivated by the desire to understand the motions of the Sun, Moon, planets, and stars. The two-body problem has been solved, as well as the restricted three-body problem, but the general problem is more difficult due to time and space distortions.