Treecode2: the power of pluralism – I. Static tests

ABSTRACT I describe an ‘oct-tree’ N-body code that randomly shifts, reorients, and resizes the root cell at each time-step. Averaging over a plurality of root cell positions and orientations statistically restores translational and rotational invariance. The potentials and forces that result can be much more accurate than those obtained from a single force calculation. In this paper, the principle of averaging is tested on static configurations. The next paper will show how this technique can substantially improve global energy, momentum, and angular momentum conservation at a negligible computational cost.