Computing explicitly topological sequence entropy: the unimodal case

Computing the Topological Entropy of unimodal Maps

We derive an algorithm to determine recursively the lap number (minimal number of monotone pieces) of the iterates of unimodal maps of an interval with free end-points. The algorithm is obtained by the sign analysis of the itineraries of the critical point and of the boundary points of the interval map. We apply this algorithm to the estimation of the growth number and the topological entropy o...

Topological Sequence Entropy

Homoclinic Tangencies in Unimodal Families with Non-constant Topological Entropy

Let C r ((0; 1]) denote the metric space of C r self-maps of 0; 1] and C s;r ((0; 1]) denote the metric space of C s families of maps in C r ((0; 1]) with the parameter space 0; 1]. Let Hs;r be the unimodal families with non-constant topological entropy in C s;r ((0; 1]). We show that for s 0, r 2, there is an open and dense subset Gs;r of Hs;r such that each family in Gs;r has a map with a hom...

Explicitly Computing Modular Forms

This is a textbook about algorithms for computing with modular forms. It is nontraditional in that the primary focus is not on underlying theory; instead, it answers the question “how do you explicitly compute spaces of modular forms?”

Unimodal Category and Topological Statistics

We consider the problem of decomposing a compactly supported distribution f : Rn → [0,∞) into a minimal number of unimodal components by means of some convex operation (e.g., sum or sup). The resulting “unimodal category” of f is a topological invariant of the distribution which shares a number of properties with the Lusternik-Schnirelmann category of a topological space. This work introduces t...