University of Minnesota math professor Donald Kahn died Friday evening at age 79.

Kahn was the husband of state representative Phyllis Kahn.  She represents District 60B which includes the University of Minnesota and the surrounding area. The two met at Cornell University and were married for 58 years according to the Star Tribune.

“He was a good political strategist — he always helped Phyllis on all of her campaigns,” attorney Brian Rice, a family friend who has worked on Phyllis Kahn’s campaigns told the Star Tribune.  “He was so supportive of everything she did.”

Kahn was also a photographer and cellist.  He earned a Ph.D in mathematics from Yale Univeristy in 1961. Before teaching a the University of Minnesota, he also taught at Columbia University.