Periodic Orbits for Billiards on an Equilateral Triangle
Periodic Orbits for Billiards on an Equilateral Triangle
1. INTRODUCTION. The trajectory of a billiard ball in motion on a frictionless billiards table is completely determined by its initial position, direction, and speed. When the ball strikes a bumper, we assume that the angle of incidence equals the angle of reflection. Once released, the ball continues indefinitely along …