Celebratio Mathematica

Thomas Milton Liggett

A tribute to my advisor Thomas M. Liggett

by Paul Jung

Remembering Tom

Early in the year 2000, I was ex­cited to start read­ing re­search pa­pers in the area of Har­mon­ic Ana­lys­is for my thes­is, when my good friend Sun­eal sug­ges­ted that I sit in one of Tom Lig­gett’s lec­tures in gradu­ate prob­ab­il­ity the­ory. I told him that it was already the second week of classes out of ten (UCLA is on a quarter sys­tem), and to be hon­est, I had no in­terest in prob­ab­il­ity. Sun­eal in­sisted that Tom was the best lec­turer he had seen in a long time, and nagged me to sit in just one class, and so I did. After that class, I agreed that Tom was an in­spir­ing lec­turer. Just like his books and re­search pa­pers, Tom’s teach­ing was crys­tal clear. When ex­plain­ing a proof, he ef­fort­lessly poin­ted out how each as­sump­tion in the the­or­em played its role. After sit­ting in a couple more classes, I en­rolled in the course. A year later, I was study­ing un­der Tom’s guid­ance for my Ph.D. thes­is.

I was Tom Lig­gett’s eighth and pen­ul­tim­ate stu­dent. Tom was a won­der­ful ad­visor for a stub­born gradu­ate stu­dent like me. He was ever un­der­stand­ing and for­giv­ing of my brash­ness, and his guid­ance was poin­tedly thought­ful — know­ing ex­actly when to nudge, when to gently ad­mon­ish, and when and how to en­cour­age. He re­mained an al­ways will­ing and open ment­or for al­most two dec­ades after his ad­vising du­ties were of­fi­cially over.

My in­ter­ac­tions with Tom over the years taught me many les­sons, whose im­port­ance tran­scen­ded math­em­at­ics. For in­stance, by be­ing gra­cious to me, he taught me to be gra­cious to oth­ers. He also taught me by ex­ample to be self­less as an edu­cat­or and teach­er.

I al­ways en­joyed spend­ing time with Tom, and made it a point to vis­it him whenev­er I was in Los Angeles. Con­ver­sa­tions with him were both fun and en­light­en­ing. In the months since he passed away, I have some­times found my­self smil­ing in memory of a com­ment he once made or a story he once told me, and at oth­er times pon­der­ing how Tom might ap­proach a prob­lem when I’ve seem­ingly ex­hausted all my op­tions. Tom touched the people around him deeply, and while his per­son may be gone, his in­flu­ence and spir­it live on vividly in our memor­ies.

Paul Jung is a Pro­fess­or in the De­part­ment of Math­em­at­ic­al Sci­ences at the Korea Ad­vanced In­sti­tute of Sci­ence and Tech­no­logy (KAIST) in South Korea.