Serge Lang was a frequent visitor to our department. He spent many summers in Berkeley and often gave lectures to the Math Undergraduate Student Association (MUSA) after students returned to campus at the end of August. Each year from 1999 to 2005, Serge gave a MUSA lecture at 4PM on the first day of classes. MUSA and the Department of Mathematics continue the tradition by hosting a Serge Lang Undergraduate Lecture each fall (or occasionally spring).
The 2026 Serge Lang Undergraduate Lecture will be given on Thursday September 17th by Professor Colin Defant - Harvard University
Room 129 - Undergrad Academic Building (UAB), 4 p.m. - 5 p.m.
Title: Combinatorial Billiards
Abstract: Billiards is a broad subject concerning trajectories of (idealized) light beams that move through a space, occasionally changing direction when they encounter certain obstructions. Combinatorial billiards focuses on billiard trajectories that are so rigid that they can be modeled using combinatorics, algebra, or probability. I will discuss multiple combinatorial billiard systems, each with a distinct flavor. The talk will mention several open problems and will encourage the audience to ponder new questions.
Past Serge Lang Undergraduate Lecturers
2025-26 Federico Ardila-Mantilla
2024-25 Stefan Steinerberger
2023-24 Ken Ono
2022-23 Jeffrey Lagarias
2021-22 Stephon Alexander
2020-21 Steven Strogatz
2019-20 Persi Diaconis
2018-19 Helene Barcelo
2017-18 Keith Devlin
2016-17 Ravi Vakil
2015-16 Brian Conrad
2014-15 Tony DeRose
2013-14 Bjorn Poonen
2012-13 John Baez
2011-12 Jordan Ellenberg
2010-11 Andrew Granville
2009-10 Benedict H. (Dick) Gross
2008-09 Peter W. Jones
2007-08 John H. Conway
2006-07 William Stein