📝 SummarXiv

Abstract

We describe the boundary of chaos separating regions of parameter space with positive topological entropy from those with zero topological entropy for a class of piecewise smooth maps. This coincides with the boundary of positive Hausdorff dimension for the survivor sets of a class of open maps. There are precisely two types of codimension one transitions across the boundaries. One of these involves heteroclinic connections, and in this case there is a finite number of periodic orbits at the transition point. The other involves an infinite cascade of bifurcations creating infinitely many periodic orbits on the boundary in a sequence called the anharmonic cascade.