Topological entropy of homoclinic closures

Abstract

In this paper we study the topological entropy of certain invariant sets of diffeomorphisms, namely the closure of the set of transverse homoclinic points associated with a hyperbolic periodic point, in terms of the growth rate of homoclinic orbits. First we study homoclinic closures which are hyperbolic in n n -dimensional compact manifolds. Using the pseudo-orbit shadowing property of basic sets we prove a formula similar to Bowen’s one on the growth of periodic points. For the nonuniformly hyperbolic case we restrict our attention to compact surfaces.