Obituary: Gregory Kriegsmann

It is with great sadness that we note the passing of mathematician Gregory Anthony Kriegsmann in May 2018.

Greg was born in 1946 and grew up in Chicago, Ill., as one of two sons of a sheet metal worker and a homemaker. He earned a B.S. in electrical engineering at Marquette University; an M.S. in both electrical engineering and mathematics from the University of California, Los Angeles (UCLA); and a Ph.D. in mathematics under the supervision of Charles Lange, also from UCLA. Greg traveled to Los Angeles as a Hughes Master Fellow, which allowed him to obtain his master’s degrees while working part-time at Hughes Aircraft Company.

Greg had an abiding affection for the Midwest and all things related to electromagnetism, wave propagation, and applied mathematics. His early interest in electrical engineering persisted, and time away from work often involved studying or building electrical circuits and practicing his skills with amateur/ham radio. “Greg doesn’t need to take vacations,” his wife Barbara quipped, as work and play were the same to him. Nathaniel (Nick) Grossmann, a professor at UCLA, remembers working with Greg to solve problems—for fun—from SIAM Review’s “Problems” section.

Upon graduating from UCLA in 1974, Greg—along with his wife and their two sons—moved east and became an instructor at New York University’s Courant Institute of Mathematical Sciences. While at Courant, he worked with Cathleen Morawetz and initiated a long-term collaboration with Edward Reiss. Greg then returned to Hughes Aircraft for one year before taking positions in the University of Nebraska-Lincoln’s Department of Mathematics (1977-1980)—where he received tenure—and Northwestern University’s Department of Engineering Sciences and Applied Mathematics (1980-1990). Following this, he became Foundation Chair and Distinguished Professor of Mathematics at the New Jersey Institute of Technology (NJIT), where he also served as department chair from 1992 to 1996.

At NJIT, Greg worked with Daljit Ahluwalia and Robert Miura to attract, employ, and support a number of new faculty hires. One cannot overstate the thought, support, and mentoring advice that he offered, especially to young faculty.

Greg’s research centered primarily on wave propagation and scattering for acoustic and electromagnetic fields. The main tools of his craft were asymptotic, perturbation, and computational methods. A hallmark of Greg’s work was his formulation and reduction of a complex and apparently-intractable problem to a simpler form that was more amenable to analysis but still retained the original’s essence.

Greg published work both independently and with co-authors from a broad representation of fields. His publications—well over 100—have appeared in a wide variety of well-respected applied mathematics and disciplinary journals. Noteworthy among them are the SIAM Journal on Applied Mathematics, the SIAM Journal on Scientific and Statistical Computing (as it was then known), Physics of Fluids, the Journal of Physical Oceanography, IEEE Transactions on Antennas and Propagation, the Journal of the Acoustical Society of America, the Journal of Elasticity, IEEE Transactions on Circuit Theory, Communications on Pure and Applied Mathematics, and the Journal of Computational Physics.

Greg advised or co-advised a total of 18 Ph.D. students, 11 at Northwestern and seven at NJIT. He served on editorial boards of a number of journals, including the SIAM Journal on Applied Mathematics, the IMA Journal of Applied Mathematics, the Journal of Engineering Mathematics, the Journal of Analysis and Applications, the Journal of Electromagnetic Waves and Applications, and Wave Motion.

From 1998 to 2002, Greg was editor-in-chief of the SIAM Journal on Applied Mathematics. A stint as SIAM Vice President for Publications soon followed. He was a member of SIAM’s inaugural class of fellows, as well as a fellow of the Institute for Mathematics and its Applications (U.K.), the Acoustical Society of America, and the Electromagnetics Academy.

Greg is survived by his wife Barbara, their sons Karl and James (and their families), and his brother John Kenneth. He will be sorely missed by his many friends, colleagues, collaborators, students, and mentees.