The Bruck–Ryser–Chowla theorem stands as a fundamental result in the field of combinatorics, identifying conditions under which certain finite projective planes cannot exist. Herbert John Ryser, a United States mathematician, developed this and other significant analytical tools throughout a career centered on combinatorial designs, finite set systems, and the theory surrounding the permanent of a matrix.
Academic Foundation
Born in Milwaukee in 1923, Ryser pursued his higher education at the University of Wisconsin–Madison. He completed his Bachelor of Arts in 1945, followed by a Master of Arts in 1947. In 1948, he earned his doctorate with a thesis titled Rational Vector Spaces, supervised by Cornelius Joseph Everett, Jr. and Cyrus C. MacDuffee.
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Following his doctoral work, Ryser spent a year at the Institute for Advanced Study in Princeton. He subsequently held faculty positions at Ohio State University before moving to Syracuse University in 1962. His career culminated in 1967 when he joined the faculty at the California Institute of Technology. Throughout his tenure, he mentored several doctoral students, including Richard A. Brualdi, Clement W. H. Lam, and Marion Tinsley.
Research and Editorial Contributions
Ryser’s scholarship focused on combinatorial matrix theory and combinatorial functions. His 1963 book, Combinatorial Mathematics, published by the Mathematical Association of America, served as the fourteenth volume in the Carus Mathematical Monographs series. Additionally, he served as an editor for professional journals, including the Journal of Combinatorial Theory, the Journal of Algebra, and Linear and Multilinear Algebra.
Legacy
Ryser died in 1985 in Pasadena. Following his death, the Journal of Combinatorial Theory, Series A published a two-part memorial issue in his honor. His estate established the H. J. Ryser Scholarships at the California Institute of Technology to support undergraduate mathematics students. In 1991, a volume titled Combinatorial matrix theory was published, co-authored by Richard A. Brualdi and Ryser.
Fast facts
- Born: 1923, Milwaukee
- Died: 1985, Pasadena
- Citizenship: United States
- Alma Mater: University of Wisconsin–Madison
- Key Field: Combinatorics
- Major Work: Combinatorial Mathematics (1963)
- Professional Affiliation: California Institute of Technology
Questions readers ask
What is Ryser's formula?
It is a mathematical method used for the computation of the permanent of a matrix.
Where did Herbert John Ryser teach?
He held academic positions at Ohio State University, Syracuse University, and the California Institute of Technology.
Achievements
- Held posts at California Institute of Technology and Syracuse University
- Fields: combinatorics and mathematics
