Kleinian groups | Conjectures that have been proved | Theorems in analysis

Ahlfors measure conjecture

In mathematics, the Ahlfors conjecture, now a theorem, states that the limit set of a finitely-generated Kleinian group is either the whole Riemann sphere, or has measure 0. The conjecture was introduced by Ahlfors, who proved it in the case that the Kleinian group has a fundamental domain with a finite number of sides. proved the Ahlfors conjecture for topologically tame groups, by showing that a topologically tame Kleinian group is geometrically tame, so the Ahlfors conjecture follows from Marden's tameness conjecture that hyperbolic 3-manifolds with finitely generated fundamental groups are topologically tame (homeomorphic to the interior of compact 3-manifolds). This latter conjecture was proved, independently, by and by . also showed that in the case when the limit set is the whole sphere, the action of the Kleinian group on the limit set is ergodic. (Wikipedia).

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Related pages

Riemann sphere | Kleinian group | Mathematics | Fundamental domain | Hyperbolic 3-manifold | Limit set