Prof. Nikolaus Vonessen received his Ph.D. from MIT in 1988. His general research interests lie in ring theory, division algebras, and invariant theory. Much progress has been made in recent decades in understanding the structure of noncommutative rings and algebras. This makes it possible to study group actions and related invariant-theoretic questions in this setting. Prof. Vonessen's work in this direction is based on two different developments: first on the deep and well-understood commutative invariant theory, classical and geometric; and second, on the theory of finite group actions on noncommutative rings, which attracted much attention during the seventies and early eighties. In his research, he has been primarily concerned with actions of linear algebraic groups; one can call this area of research noncommutative invariant theory.

Prof. Vonessen is also interested in studying the structure of non-commutative rings and algebras. In particular, he has investigated the structure of polynomial identity rings, and studied (jointly with Prof. Braun of the University of Haifa, Israel) the concept of integrality for extensions of such rings; this extends work by Krull in the commutative setting. In recent years he has also studied, together with Prof. Reichstein of the University of British Columbia, division algebras, and actions of algebraic groups on division algebras and central simple algebras.