A lower bound on entropy for some differmorphisms of the annulus
by
Thor Matison
Montana State University
Coauthors: Marcy Barge (Montana State University)

Let F be an orientation preserving diffeomorphism of the annulus A. Suppose that there exists a compact, connected F-invariant set \Delta subset \intA that irreducibly separates A into exactly two components, one containing the inner and the other containing the outer boundary circle of A. Further suppose that \Delta contains two periodic points, each having a stable manifold that meets both of the complementary components of \Delta. We give a lower bound on the topological entropy of F based on the rotation numbers of these periodic points.

Date received: February 26, 1997

Copyright © 1997 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # caam-20.