Harold Widom

Widom died from complications of COVID-19 at his home in Santa Cruz, California, on January 20, 2021, at age 88.

Widom was appointed in the Department of Mathematics at the University of California, Santa Cruz, and became professor emeritus in 1994. His research areas were in integral equations and operator theory, in particular the determination of the spectra of a semi-infinite Toeplitz matrix and Wiener-Hopf operators, and the asymptotic behavior of the spectra of various classes of operators. The latter was looked at from the point of view of pseudodifferential operators (which generalize both integral and partial differential operators) on manifolds.

Widom was born in Newark, New Jersey. He studied at Stuyvesant High School, graduating in 1949, and was a member of the school's math team along with his brother Benjamin Widom (1944, 1948). Widom attended City College of New York until 1951, during which he was one of the winners of the William Lowell Putnam Mathematical Competition (1951). At the University of Chicago he obtained an M.S. (1952) and Ph.D., the latter on a thesis Embedding of AW*-algebras advised by Irving Kaplansky (1955). He taught mathematics at Cornell University (1955–68) where he started his work on Toeplitz and Wiener-Hopf operators, partly inspired by Mark Kac.

Harold Widom (September 23, 1932 – January 20, 2021) was an American mathematician best known for his contributions to operator theory and random matrices. He was appointed to the Department of Mathematics at the University of California, Santa Cruz in 1968 and became professor emeritus in 1994.