Outer billiards and the plaid model
Professor Richard Schwartz
Brown University
Outer billiards is a dynamical system that involves a point circulating around the outside of a convex shape in the plane sort of like the earth orbiting around the sum. The name comes from the fact that the rules for the system resemble the rules for ordinary billiards. I show some computer pictures and demonstrations of outer billiards, and then narrow the focus and explain how I figured out a combinatorial model (which I call the plaid model) for what happens when the convex shape is a kite.
Rich Schwartz got his Ph.D. in math from Princeton in 1991 and since then has had a number of university jobs, the last one being the Chancellor’s Professor of Mathematics at Brown University. In his spare time, Rich enjoys drawing, listening to music, computer programming, cycling, walking on the beach, and working out at the gym.
