### Memorial resolution for Clarence Wilkerson

**01-10-2020**

Clarence Wilkerson, Professor Emeritus of Mathematics, died on August 17, 2019 in College Station, TX.

Clarence was born to Clarence Sr. and Dorthea Wilkerson in Laredo, TX and was later raised in Donna, TX. As a young man, Clarence was active in the Boy Scouts of America, achieving the rank of Eagle. At the age of 16 he received the Carnegie Medal for Heroism. He attended Rice University on a National Merit Scholarship, earning a B.A. with honors in Mathematics in 1966. He earned his Ph.D., also at Rice, in 1970, with support from an NSF Predoctoral Fellowship.

Professor Wilkerson began his academic career at the University of Hawaii, where he was Assistant Professor from 1970-72. He then held two one-year postdoctoral fellowships, first at the ETH in Zurich and then at Carleton University in Ottawa, Ontario. He held faculty appointments at the University of Pennsylvania (1974-77) and then at Wayne State University (1977-89), where he advanced to the rank of Professor and served for two years as Chair of the Mathematics Department. In the spring of 1980, Professor Wilkerson was a member of the Institute for Advanced Studies in Princeton, and in 1982, he was an invited member of the Institute for Advanced Studies of Hebrew University. He was also a Visiting Professor at Notre Dame, Cornell, the University of Chicago, and the University of Rochester, and was invited for extended visits to universities in England, France, Spain, Germany, Mexico, and Switzerland. In 1989, Clarence was appointed Professor of Mathematics at Purdue.

Clarence’s research was in algebraic topology. He was particularly well known for his work with William Dwyer of Notre Dame on a classification and tools related to H-spaces. These spaces are the algebraic topological analogs of Lie groups, which are of fundamental importance in diverse fields such as quantum mechanics, number theory, and algebraic geometry. However, Lie groups are defined geometrically in way that is somewhat rigid, while H-spaces are defined with more flexible topological ideas. A central question in this field was the relationship between H-spaces and Lie groups and exactly what H-spaces actually exist. The work of Wilkerson and Dwyer led to a complete classification of H-spaces, a problem that was open for almost 60 years, and to the solution of a wide range of other problems related to H-spaces.

Professor Wilkerson received a Sloan Research Fellowship in 1978. He gave over 150 invited talks at regional, national, and international conferences and meetings, and was invited twice to give one-hour addresses to regional American Mathematical Society meetings. In 2013 he was inducted into the inaugural class of Fellows of the American Mathematical Society. He was well-known by his colleagues not only for his intellect, but also for his sharp wit and sarcastic sense of humor.

Clarence retired from Purdue in 2010 and was named Professor Emeritus. At that time, he and his wife returned to Texas where he continued to teach Mathematics at Texas A&M.

Clarence is survived by Sharon, his wife of 53 years; his two sons, Wendell and Christopher; his brother, Michael; and his two grandchildren, Taylor and Alex.