Double coset density in classical algebraic groups

Brundan, Jonathan

doi:10.1090/S0002-9947-99-02258-8

Double coset density in classical algebraic groups
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Trans. Amer. Math. Soc. 352 (2000), 1405-1436 Request permission

Abstract:

We classify all pairs of reductive maximal connected subgroups of a classical algebraic group $G$ that have a dense double coset in $G$. Using this, we show that for an arbitrary pair $(H, K)$ of reductive subgroups of a reductive group $G$ satisfying a certain mild technical condition, there is a dense $H, K$-double coset in $G$ precisely when $G = HK$ is a factorization.

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