Roger Wolcott Richardson 1930–1993

Roger Wolcott Richardson (1930–1993) was an American-born mathematician who studied at Harvard and the University of Michigan before holding posts at Princeton, the University of Washington, and Durham, eventually settling at the Australian National University in 1978. His most celebrated contribution, now known as the "Richardson orbit," concerns dense orbits of parabolic subgroups on unipotent radicals, and became a foundational tool in the classification of unipotent conjugacy classes in algebraic groups. Beyond this landmark result, his career spanned deformation theory of Lie algebras, geometric invariant theory, and – in his final years, with collaborator Mike Field – equivariant bifurcation theory, where their work disproved the influential Maximal Isotropy Subgroup Conjecture. Elected to the Australian Academy of Science in 1990, Richardson died in 1993 from a rare and difficult-to-diagnose lymphoma, at what colleagues described as a particularly productive point in his research career.

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About this memoir

This memoir was originally published in Historical Records of Australian Science, vol. 11(4), 1996. It was written by G.I. Lehrer, Centre for Mathematics and its Applications, Australian National University, A.C.T. 0200.