MSCS Graduate Student Seminar
Fall 2000
September 22
SPEAKER: Howard Masur
TITLE: Arithmetic failure of ergodicity in billiards
ABSTRACT: Billiards give important examples of dynamical systems and
ergodicity is a major issue in the subject. I will give an introduction
to the dynamics of billiards and talk about the recent Ph.D. dissertaion
of my student, Yitwah Cheung, who studied ergodicity of billiards in
rectangles with barriers and related it to some basic number theory. As
part of this talk I will introduce the notion
of the Hausdorff dimension of a set of real numbers.