On the infinitesimal orbit type of maximal dimensional orbits

Autor: D. Szeghy
Rok vydání: 2014
Předmět:
Zdroj: Differential Geometry and its Applications. 35:86-105
ISSN: 0926-2245
DOI: 10.1016/j.difgeo.2014.04.013
Popis: We prove that in the case of an isometric action α : G × M → M of a Lie group G on a semi-Riemannian manifold M the union of the maximal dimensional orbits is an open and dense set in M. Moreover, if M is a Lorentz manifold and α is an isometric action on it, then in the set of the maximal dimensional orbits local stability and normalizability are equivalent, and there is no open invariant set U ⊂ M such that all the orbits G ( x ) ⊂ U are non-normalizable and have the same infinitesimal type. These results are useful in the extension of the principal orbit type theorem.
Databáze: OpenAIRE