In Memoriam: Patrick Ahern

Patrick Ahern died on September 26, 2023.  He was an emeritus professor of our department, serving as a faculty member from 1966-2006.

Pat was born in Albert Lea Minnesota in 1936, to Garrett Patrick and Marion Dorothy (Doran) Ahern. He graduated from Albert Lea high school, where his father was a math teacher and football coach and Pat excelled at math and football, as well as other classes and sports. He promptly earned bachelor’s, master’s, and Ph.D. degrees in math from the University of Minnesota. His studies were supported with a National Science Foundation Graduate Fellowship, awarded in 1960.

After Pat earned tenure in 1970, he took the family for a year’s sabbatical to Pisa, Italy, the first of many international trips for the Ahern family. At various times over the years Pat was fluent in Spanish, French, Italian, and Serbo-Croatian, and conversational in other languages. Prominent mathematicians from around the world knew him as a co-author, mentor, and friend. The life he shared with his family was rich with explorations, adventures, cultures, and cuisines.

During his 42-year career at the University of Wisconsin-Madison he instructed thousands of undergraduates, mentored dozens of graduate students, collaborated with colleagues, and produced a steady stream of innovative research. Pat’s area was analysis, the complexity of which is reflected in the title of his most cited paper according to Web of Science: “A theorem of Brown-Halmos type for Bergman space Toeplitz operators.” He built elegant, symbolic models in pursuit of math’s most elusive secrets, exercises in thought every bit as long, difficult, and lonely as one of his epic and grueling bike rides through the rolling hills of Southern Wisconsin. Time vanquished Pat’s ability to continue these pursuits, but in his prime he thought astoundingly deeply, and could climb impressive heights with enviable strength.

Pat will be remembered fondly by his family, colleagues, collaborators, friends, and students. In lieu of flowers, the family welcomes donations in Pat’s name to Agrace hospice in Madison, WI, or to the Alzheimer’s Association.