Richard Albert Dean (BS '45), a professor of mathematics at Caltech from 1955 to 1987, passed away on January 27, 2022, at the age of 97.

Dean was born in 1924 in Columbus, Ohio. He earned an undergraduate degree from Caltech in 1945 and a PhD from Ohio State University in 1953. He taught mathematics at Middlebury College in Vermont in 1947. Dean returned to Caltech in 1954 as the Harry Bateman Research Fellow before joining the faculty as an assistant professor in 1955. Dean was named associate professor in 1959, professor in 1966, and professor emeritus in 1987.

Dean's achievements in mathematics include showing that the word problem in a finite presented lattice (a certain type of algebraic structure coming from order theory) is

solvable. He later applied lattice theory to problems in economics. He authored two algebra textbooks, Elements of Abstract Algebra (1966) and Classical Abstract Algebra (1990), and co-authored the high school algebra textbook Arithmetic and Calculators: How to Deal with Arithmetic in the Calculator Age (1978).

Dean served as a lieutenant in the United States Navy from 1943 to 1946, and 1952 to 1954, and as a consultant for the National Security Agency from 1955 to 1963. He was a member of the American Mathematical Society and the Mathematics Association of America. He earned an honorary doctorate of science from Denison University in Ohio in 1973.

Dean also served as an admissions officer at Caltech. "This was very important to him, because he felt that he was able to give a chance to students who didn't necessarily 'check all the boxes' but showed great drive," says Jason Dean, Richard's son, who is now a researcher in sociology at the University of Strasbourg in France.

In addition to his son, Dean is survived by his second wife, Carol K. Dean, formerly of Pasadena City College; four grandchildren; and four great-grandchildren.

Written by Whitney Clavin