Sur les composantes exotiques des espaces d'actions de groupes de surfaces sur le plan hyperbolique
Auteur / Autrice : | Maxime Wolff |
Direction : | Louis Funar |
Type : | Thèse de doctorat |
Discipline(s) : | Mathématiques |
Date : | Soutenance en 2007 |
Etablissement(s) : | Université Joseph Fourier (Grenoble ; 1971-2015) |
Mots clés
Mots clés contrôlés
Mots clés libres
Résumé
Let R,. Denote the space of representations of a surface group of genus g in PSL(2,R). By a theorem of W. Goldman, the space R,. Has 4g-3 connected components, indexed by the Euler class e:Rg-> Z, which satisties the Milnor-Wood inequality. The quotient space Rg/PSL(2,R) has the name number of connected components, two of which are identitied with the Teichmüller space of the surface. These two connected components i consist of ail the faithful and discrete representations. We tirst prove that the set of non-injective representations is dense in ail the other connected components, and that the set of representations wbich are discrete or elementary is closed and nowhere dense in these exotic components. Then we consider the Bestvina-Paulin compactification of the space Rg/PSL(2,R), which generalizes the Thurston compactification of Teichmüller spaces. We show that tbis compactification is very degenrated, and we show that it is much more natural to consider another compactitication, which takes into account the orientation of the plane.