Epimorphic subgroups of algebraic groups

Michel Brion (1)

1 IF - Institut Fourier

In this note, we show that the epimorphic subgroups of an algebraic group are exactly the pull-backs of the epimorphic subgroups of its affinization. We also obtain epimorphicity criteria for subgroups of affine algebraic groups, which generalize a result of Bien and Borel. Moreover, we extend the affinization theorem for algebraic groups to homogeneous spaces.

Domaines: Mathématiques [math]

Michel Brion. Epimorphic subgroups of algebraic groups. Mathematical Research Letters, 2017, 24 (6), pp.1649-1665. ⟨hal-02020792⟩