Robert Edward Welsh, 91, died on September 10, 2024. Born and raised in Pittsburgh, Pennsylvania, Bob graduated from Georgetown University and received his Ph.D. in Physics from Penn State. He served in the US Air Force from 1955-1957 as a nuclear weapons officer, after which he completed a post-doctoral fellowship at Carnegie Institute of Technology (now Carnegie Mellon University). As a professor in the William and Mary Physics Department from 1963 to 2007, Bob’s research focused on experimental particle physics, about which he published numerous articles based on research at a variety of laboratories, both national and international. In collaboration with colleagues from the W&M Biology Department, he also studied the use of nuclear physics in biological/medical applications. He taught undergraduate and graduate classes, and supervised postdoctoral fellows, graduate and undergraduate students. Bob served as chair of the Physics Department from 1988 to 1991 and received the Thomas Jefferson Award for Outstanding Faculty in 1985. He also served as the Director of the Student Affairs Office at Jefferson Laboratory from 1997 to 2007.

Bob brought to his hobbies the same passion, precision, and patience that he inspired in his professional colleagues and students.  Just as he found in the subatomic word a marvelous challenge to human ingenuity, he loved to pit his wits against more ordinary mysteries.  Cryptography, the science of codes and cyphers, with particular emphasis on the WWII Enigma machine, was  the subject of many of his lectures to lay audiences.  How Things Work, the title of a freshman course he taught for years, aptly sums up Bob’s infectious curiosity.

He is survived by his wife of thirty-six years, Karen Rose; sons, Patrick (Amber), Richard (Leah), Edward (Beth); daughters, Maia and Robin; and grandchildren, Dalia and Micah. He was preceded in death by his wife, Rita (Varnes), his parents, Maurice and Mary Regina (Jacob), his sister, Dorothy (Aiken) and his brother, Maurice.

The family wishes to thank the staff at Amedisys Hospice and the Williamsburg Landing Health and Rehabilitation Center for their care and support during Bob’s last weeks.