{ "id": "0903.2419", "version": "v1", "published": "2009-03-13T16:10:58.000Z", "updated": "2009-03-13T16:10:58.000Z", "title": "Flows, Fixed Points and Rigidity for Kleinian Groups", "authors": [ "Kingshook Biswas" ], "categories": [ "math.GT", "math.DS" ], "abstract": "We study the closed group of homeomorphisms of the boundary of real hyperbolic space generated by a cocompact Kleinian group $G_1$ and a quasiconformal conjugate $h^{-1}G_2 h$ of a cocompact group $G_2$. We show that if the conjugacy $h$ is not conformal then this group contains a non-trivial one parameter subgroup. This leads to rigidity results; for example, Mostow rigidity is an immediate consequence. We are also able to prove a relative version of Mostow rigidity, called pattern rigidity. For a cocompact group $G$, by a $G$-invariant pattern we mean a $G$-invariant collection of closed proper subsets of the boundary of hyperbolic space which is discrete in the space of compact subsets minus singletons. Such a pattern arises for example as the collection of translates of limit sets of finitely many infinite index quasiconvex subgroups of $G$. We prove that (in dimension at least three) for $G_1, G_2$ cocompact Kleinian groups, any quasiconformal map pairing a $G_1$-invariant pattern to a $G_2$-invariant pattern must be conformal. This generalizes a previous result of Schwartz who proved rigidity in the case of limit sets of cyclic subgroups, and Biswas-Mj who proved rigidity for Poincare Duality subgroups.", "revisions": [ { "version": "v1", "updated": "2009-03-13T16:10:58.000Z" } ], "analyses": { "subjects": [ "57M50" ], "keywords": [ "fixed points", "cocompact kleinian group", "invariant pattern", "compact subsets minus singletons", "cocompact group" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0903.2419B" } } }