by Shannon Starr
I am grateful to be able to recall fond memories of time I spent at UCLA when I got to know Tom Liggett. I was a visiting research assistant professor in 2005 and 2006. I interacted with the probability group led by Tom, Marek Biskup, Lincoln Chayes and Roberto Schonmann. The postdocs in the group were Yevgeniy Kovchegov and Noam Berger.
Tom was the undergraduate vice-chair and gave much good advice in teaching. I remember he mentioned that he taught during the Vietnam War, and if he would not bend the rules for grading then, students could be assured that he would not do it any time else. I remember that Tom disliked the idea of a draft for the military in America. At that time, some folks thought the idea of a draft would make Americans take their entanglements in wars more seriously. But Tom thought the idea was unethical.
I remember that I was interested in B. F. Skinner at that time. Tom noted that many people had been interested in him, but many years earlier.
Tom was one of the most decent people I had the pleasure of meeting. His son was a school teacher at the time. His daughter was an ordained minister. He invited the group to his house for a party and I had a wonderful conversation with her.
Tom gave a course on interacting particle processes. At the end Lincoln suggested we all bring in our textbooks and Tom would sign them. I still have mine. It is a cherished possession.
I saw Tom after those years, too. He described his work with Pietro Caputo and Thomas Richthammer on a proof of an interesting conjecture by David Aldous for the spectral gap of the simple exclusion process on any finite graph. He said the collaboration was like the Borromean rings: if you remove the contribution of any one, the other two would not hold together. It was an essential combination of all three together.
Shannon Starr is Associate Professor of Mathematics at the University of Alabama.
