Lower Bound For Dilatations

Abstract

We prove a new lower bound for the dilatation of an arbitrary pseudo-Anosov map on a surface of genus g with n punctures. Our bound improves the former super-exponential dependence on the genus by a polynomial dependence.

arXiv commentAccepted for publication by the Journal of Topology, 14 pages, Exposition improved, preliminaries and an appendix are added