Non-existence de certains polygones généralisés, I.
Non-existence de certains polygones généralisés. II.
Normale Einbettungen von G..U .
Normalizers and self-normalizing subgroups II
Let be a field, G a reductive algebraic -group, and G 1 ≤ G a reductive subgroup. For G 1 ≤ G, the corresponding groups of -points, we study the normalizer N = N G(G 1). In particular, for a standard embedding of the odd orthogonal group G 1 = SO(m, ) in G = SL(m, ) we have N ≅ G 1 ⋊ µm(), the semidirect product of G 1 by the group of m-th roots of unity in . The normalizers of the even orthogonal and symplectic subgroup of SL(2n, ) were computed in [Širola B., Normalizers and self-normalizing...
Observable radizielle Untergruppen von halbeinfachen algebraischen Gruppen.
On a class of groups with strongly embedded subgroup.
On certain algebraic groups attached to local number-fields.
On complete orbit spaces of SL(2) actions
On complete orbit spaces of SL(2) actions, II
The aim of this paper is to extend the results of [BB-Ś2] concerning geometric quotients of actions of SL(2) to the case of good quotients. Thus the results of the present paper can be applied to any action of SL(2) on a complete smooth algebraic variety, while the theorems proved in [BB-Ś2] concerned only special situations.
On cyclic subgroups of the group .
On finite same-invariant linear groups.
On groups with root system of type .
On maximal subgroups of the general linear group over the field of rational functions.
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 quasihomogeneous manifolds – via Brion-Luna-Vust theorem
We consider a smooth projective variety on which a simple algebraic group acts with an open orbit. We discuss a theorem of Brion-Luna-Vust in order to relate the action of with the induced action of on the normal bundle of a closed orbit of the action. We get effective results in case and .
On reducible and decomposable representations of orders.
On some geometric aspects of Bruhat orderings. I. A finer decomposition of Bruhat cells.
On some reductive group actions on affine space II.
On Structure of Weyl Modules.
On the composition factors of Weyl modules.