2/22: GaYee Park – Billiards on square-tiled surfaces

This Wednesday, 2/22, GaYee Park will give a Math Club talk about billiards on square-tiled surfaces. We meet as usual in LGRT 1528 from 5-6 pm, with pizza and soda provided. Here’s GaYee’s abstract:

Billiards on square-tiled surfaces:

If we shoot a ball from a point at a 45-degree angle on any flat bounded
surface, how does its path look like? Will the path return to its original
point? How long is each path? We already know for an n x m rectangular
surface, many properties of the path depend on the gcd (n,m) and lcm (n,m). We extend this question to other surfaces such as the Möbius strip, cylinder, Klein bottle, and others.