Entropy Scales in Topological Dynamical Systems

Abstract

Motivated by Helfter's notion of scaling, we define Bowen, upper capacity, and local measure-theoretic entropy scales. Under a controlled decay condition, we establish a variational principle on compact subsets by combining a Billingsley-type theorem with a Frostman-type construction. We also prove factor inequalities for upper capacity entropy scales on compact sets and for Bowen entropy scales on arbitrary subsets. For induced systems on spaces of probability measures, we give sufficient conditions for the preservation of zero upper capacity entropy scales and show, under an additional comparison condition, that positivity for the original system forces the induced entropy scale to be infinite. Finally, we define upper capacity entropy scales along prescribed observation times and establish the corresponding zero-level equivalence for induced systems.