October 22, 2012 ,14:00
Dr Itzhak Fouxon, Weizmann Institute
We consider elastic collisions of a small group of hard balls that are confined to a finite region of space. The history of the particle's motion consists of free motion intermitted by collisions with other particles. We study the temporal sequence of collisions of the particle. This sequence looks random because of chaoticity of collisions. We show that these random-looking sequences during long periods of time contain more collisions with certain particles and less with certain other particles. These consistent, stable, preferences can last for very long times, often for the whole time of the experiment, though eventually they do change. Thus the particles have collisional preferences due to chaos.