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| Content Provider | Springer Nature Link |
|---|---|
| Author | Zeghib, Abdelghani Dumitrescu, Sorin |
| Copyright Year | 2010 |
| Abstract | We classify three-dimensional Lorentz homogeneous spaces G/I having a compact manifold locally modeled on them. We prove a completeness result: any compact locally homogeneous Lorentz threefold M is isometric to a quotient of a Lorentz homogeneous space G/I by a discrete subgroup Γ of G acting properly and freely on G/I. Moreover, if I is noncompact, G/I is isometric to a Lie group L endowed with a left invariant Lorentz metric, where L is isomorphic to one of the following Lie groups: $${\bf R}^3, \widetilde{SL(2, {\bf R})}, He\,is \,{\rm or}\, SOL.$$ If L is not $${\widetilde{SL(2, {\bf R})}}$$ , then M admits a finite cover which is a quotient of L by a lattice.Nous classifions les géométries lorentziennes de dimension trois qui admettent des réalisations compactes. Nous démontrons un résultat de complétude : toute variété lorentzienne localement homogène compacte de dimension trois est isométrique au quotient (à gauche) d’un espace homogène lorentzien G/I de dimension trois par un sous-groupe discret Γ de G agissant proprement et librement. Si, de plus, le groupe d’isotropie locale de la métrique lorentzienne est supposé non compact, le revêtement universel de la variété est isométrique à un groupe de Lie L muni d’une métrique lorentzienne invariante par translation à gauche et L est isomorphe à l’un des groupes suivants : $${{\bf R}^3, \widetilde{SL(2, {\bf R})}, He\,is}$$ ou SOL. Si L n’est pas $${\widetilde{SL(2, {\bf R})}}$$ , alors la variété admet un revêtement fini qui est isométrique à un quotient de L par un réseau. |
| Ending Page | 273 |
| Page Count | 31 |
| Starting Page | 243 |
| File Format | |
| ISSN | 00465755 |
| e-ISSN | 15729168 |
| Journal | Geometriae Dedicata |
| Issue Number | 1 |
| Volume Number | 149 |
| Language | English |
| Publisher | Springer Netherlands |
| Publisher Date | 2010-03-05 |
| Publisher Place | Dordrecht |
| Access Restriction | One Nation One Subscription (ONOS) |
| Subject Keyword | Geometry Lorentz metrics, indefinite metrics Locally homogenous Lorentz manifolds Transitive Killing Lie algebras Geodesics Lorentz manifolds, manifolds with indefinite metrics Completeness of (G, X)-structures |
| Content Type | Text |
| Resource Type | Article |
| Subject | Geometry and Topology |
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