Flag varieties as equivariant compactifications of G_a^n

Abstract

Let G be a semisimple affine algebraic group and P a parabolic subgroup of G. We classify all flag varieties G/P which admit an action of the commutative unipotent group G_a^n with an open orbit.

4 pages, small corrections

Cited by in corpus (2)

• Degenerate flag varieties of type A: Frobenius splitting and BW theorem
• ${\mathbb{G}}_a^M$ degeneration of flag varieties