On irreducible sl (2, R) - modules and sl 2-triples.
On normal abelian subgroups in parabolic groups
Let be a reductive algebraic group, a parabolic subgroup of with unipotent radical , and a closed connected subgroup of which is normalized by . We show that acts on with finitely many orbits provided is abelian. This generalizes a well-known finiteness result, namely the case when is central in . We also obtain an analogous result for the adjoint action of on invariant linear subspaces of the Lie algebra of which are abelian Lie algebras. Finally, we discuss a connection...
On spherical nilpotent orbits and beyond
We continue investigations that are concerned with the complexity of nilpotent orbits in semisimple Lie algebras. We give a characterization of the spherical nilpotent orbits in terms of minimal Levi subalgebras intersecting them. This provides a kind of canonical form for such orbits. A description minimal non-spherical orbits in all simple Lie algebras is obtained. The theory developed for the adjoint representation is then extended to Vinberg’s -groups. This yields a description of spherical...
On the Cartan subalgebras of Lie algebras over small fields.
On the complicatedness of the pair (g,K).
On the principal bundles over a flag manifold.
Orbites d'un groupe algébrique dans l'espace des idéaux rationnels d'une algèbre enveloppante