Periodic billiard trajectories in smooth convex bodies
arXiv:0905.1761 · doi:10.1007/s00039-009-0009-3
Abstract
We consider billiard trajectories in a smooth convex body in and estimate the number of distinct periodic trajectories that make exactly reflections per period at the boundary of the body. In the case of prime we obtain the lower bound , which is much better than the previous estimates.