-Whittaker vectors corresponding to a principal nilpotent orbit of a real reductive linear Lie group, and wave front sets
The study of diffeomorphism group actions requires methods of infinite dimensional analysis. Really convenient tools can be found in the Frölicher - Kriegl - Michor differentiation theory and its geometrical aspects. In terms of it we develop the calculus of various types of one parameter diffeomorphism groups in infinite dimensional spaces with smooth structure. Some spectral properties of the derivative of exponential mapping for manifolds are given.
We classify, up to conjugation, all subgroups of the semidirect products and . Our methods can also be applied to all Lie groups that are locally isomorphic to them.
Soit un corps local non archimédien de caractéristique résiduelle différente de et . Nous définissons strates semi-simples et caractères semi-simples pour le groupe exceptionnel à l’aide des objets analogues pour le groupe , des automorphismes de trialité et d’une correspondance de Glauberman. Nous construisons alors les types semi-simples associés et nous donnons des conditions suffisantes pour que ces types s’induisent irréductiblement, obtenant ainsi des représentations supercuspidales...
The main result of the present paper is an exact sequence which describes the group of central extensions of a connected infinite-dimensional Lie group by an abelian group whose identity component is a quotient of a vector space by a discrete subgroup. A major point of this result is that it is not restricted to smoothly paracompact groups and hence applies in particular to all Banach- and Fréchet-Lie groups. The exact sequence encodes in particular precise obstructions for a given Lie algebra...