Oct 17, 2009 - Claremont, Calif. -

Melvin Henriksen, professor of mathematics emeritus at Harvey Mudd College, passed away on Oct. 14 in Albuquerque, N.M., at the age of 82. A significant portion of his life was spent at Harvey Mudd College where he served as a professor of mathematics from 1969 to 1997. After retiring, he was a very active member of the HMC community.

“Mel was among the most published mathematicians in Claremont and had a wide array of international contacts and collaborators,” said Bob Cave, vice president for academic affairs and dean of faculty. “He did a wonderful job of raising the profile of mathematics at HMC. We will deeply miss the passion and care he continued to bring to his work each day throughout his career, as well as his sense of humor.”

Henriksen was well known in the mathematics community for his work on the study of rings of continuous functions, which involve the interplay of algebra and topology. As a major innovator in a part of topology developed mostly in the second half of the 20th century, his work on “rings of continuous functions” helped create a new field of mathematics that combines topology with modern algebra. This new mathematics started with a seminar he co-organized in 1954–55.

He’s been published in countless journals for his work on ordered rings and topology.

“Mel is just a grand old man of ordered rings,” said James Madden, Louisiana State University professor and a former student of Henriksen’s, at a Conference on Ordered Rings in 2007. “He’s dipped into every aspect of it. He’s responsible for a large research community—people who are pursuing questions he originally raised and developing ideas that hatched first in his brain.”

The conference also celebrated Henriksen’s 80th birthday.

During his diverse and varied career as a math professor, Henriksen also received recognition for his attempt to apply mathematics in order to reduce the amount of waiting time spent by citizens called for jury duty. Together with a group of six students from The Claremont Colleges and colleague George Orland, Henriksen devised a system for reducing waiting time for jurors for the Superior Court of Los Angeles County. Results from the Mathematics Clinic project boasted that their system would help save at least $73,000 a year in fees paid to jurors if it was implemented just in the Pomona Courthouse alone. They also made recommendations for further studies that could improve juror utilization.

“While most of us feel that jury duty is an obligation of citizenship, sitting in a jury waiting room day after day without even entering a courtroom is usually enough to dampen anyone’s civic ardor,” said Henriksen in the mid-1970’s.

Known for speaking his mind and articulating a clear argument, Henriksen was a staunch enforcer of having his math students write their answers in complete and logical sentences. On the first day of any class, he was sure to tell students, “I am more interested in how you arrive at answers to problems than I am in the answer itself.”

Henriksen is the unnamed third author on the well-known book Rings of Continuous Functions by Meyer Jerison and Leonard Gillman, past president of the Mathematical Association of America. Henriksen also wrote a paper with Gillman on “real closed fields” that Madden calls “an ancient monument in real algebraic geometry—Stonehenge for the discipline.” Additionally, Henriksen also helped write Single Variable Calculus with an Introduction to Numerical Methods, with M. Lees (1970), and participated in the film “Infinite Acres,” which was produced by the Mathematical Association of America in 1965.

Henriksen graduated from the City College of New York with a bachelor’s degree in mathematics in 1948. He received his master’s and Ph.D. at the University of Wisconsin in 1948 and 1951. While serving as a faculty member at HMC, Henriksen also served briefly as a visiting professor in the department of mathematics at Wesleyan University. Before coming to Mudd, he taught math at Case Western, Purdue University, Wayne State University, University of Alabama and the University of Wisconsin.

Henriksen belonged to the American Mathematical Society, the Mathematical Association of America and the National Association of Mathematics. He also directed 11 Ph.D. dissertations, seven at Purdue University, one at Case Western University and three at Claremont Graduate University.

Henriksen was an avid history buff and enjoyed traveling to collaborate with mathematicians around the world.