Simple and efficient algorithm for large scale molecular dynamics simulation in hard disk system

A simple and efficient algorithm of the molecular-dynamics simulation of the hard disk system based on the Event-Driven method is developed. From the analysis of algorithm, the complexity is O(log N) per 1 event, and the constant coefficient of the complexity is smaller than conventional efficient algorithm based on the concept of Cell-Crossing Event. The maximum performance of more than 460 millions of collisions per CPU-hour on the Alpha600 compatible in a 2500 particle system is achieved. An extension to the infinite-space system based on this algorithm is also proposed.