立石萌 氏
2022年11月24日(木) 13時30分
総合研究10号館317号室 / Zoom会議 (ハイブリッド)
A billiard system deals with the motion of a ball (point mass) on a billiard table (two-dimensional domain), which moves straight and changes its direction at the boundary so that the angle of reflection is equal to one of incidence. In this system, a map from one collision point to the next on the boundary is an area-preserving map under an appropriate coordinate, and we can show the non-existence of invariant curves under some assumption. In this talk, I will talk about one of the sufficient conditions for the non-existence of invariant curves of some billiard systems.