Irreducible geometric subgroups of classical algebraic groups

Abstract

Let $G$ be a simple classical algebraic group over an algebraically closed field $K$ of characteristic $p\ge 0$ with natural module $W$. Let $H$ be a closed subgroup of $G$ and let $V$ be a non-trivial irreducible tensor-indecomposable $p$-restricted rational $KG$-module such that the restriction of $V$ to $H$ is irreducible. In this paper we classify all such triples $(G,H,V)$, where $H$ is a maximal closed disconnected positive-dimensional subgroup of $G$, and $H$ preserves a natural geometric structure on $W$.

92 pages; to appear in Mem. Amer. Math. Soc