Actions of discrete groups on stationary Lorentz manifolds
نویسندگان
چکیده
منابع مشابه
Actions of Discrete Groups on Stationary Lorentz Manifolds
We study the geometry of compact Lorentzian manifolds that admit a somewhere timelike Killing vector field, and whose isometry group has infinitely many connected components. Up to a finite cover, such manifolds are products (or amalgamated products) of a flat Lorentzian torus and a compact Riemannian (resp., lightlike) manifold.
متن کاملIsometric actions of Heisenberg groups on compact Lorentz manifolds
We prove results toward classifying compact Lorentz manifolds on which Heisenberg groups act isometrically. We give a general construction, leading to a new example, of codimension-one actions—those for which the dimension of the Heisenberg group is one less than the dimension of the manifold. The main result is a classification of codimension-one actions, under the assumption they are real-ana...
متن کاملIsometry Groups and Geodesic Foliations of Lorentz Manifolds. Part Ii: Geometry of Analytic Lorentz Manifolds with Large Isometry Groups
This is part II of a series on noncompact isometry groups of Lorentz manifolds. We have introduced in part I, a compactification of these isometry groups, and called “bipolarized” those Lorentz manifolds having a “trivial ” compactification. Here we show a geometric rigidity of non-bipolarized Lorentz manifolds; that is, they are (at least locally) warped products of constant curvature Lorentz ...
متن کاملSome Examples of Discrete Group Actions on Aspherical Manifolds
We construct two classes of examples of a virtually torsionfree group G acting properly and cocompactly on a contractible manifold X. In the first class of examples the universal space for proper actions, EG, has no model with finitely many orbits of cells. The reason is that the centralizers of certain finite subgroups of G will not have finitetype classifying spaces. In the second class of ex...
متن کاملProper Actions of High-Dimensional Groups on Complex Manifolds
We explicitly classify all pairs (M,G), where M is a connected complex manifold of dimension n ≥ 2 and G is a connected Lie group acting properly and effectively on M by holomorphic transformations and having dimension dG satisfying n 2 + 2 ≤ dG < n 2 + 2n. These results extend – in the complex case – the classical description of manifolds admitting proper actions of groups of sufficiently high...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Ergodic Theory and Dynamical Systems
سال: 2013
ISSN: 0143-3857,1469-4417
DOI: 10.1017/etds.2013.17