On $r$-Neutralized Entropy: Entropy Formula and Existence of Measures Attaining the Supremum

TL;DR

This paper introduces the concept of r-neutralized local entropy, derives related formulas, and proves the existence and non-uniqueness of measures that maximize this entropy in hyperbolic systems, with implications for rigidity.

Contribution

It defines r-neutralized local entropy, establishes entropy formulas, and proves the existence and non-uniqueness of maximizing measures in hyperbolic systems.

Findings

r-neutralized local entropy equals Brin-Katok entropy plus r times pointwise dimension

Existence of ergodic measures that maximize r-neutralized entropy

Construction of hyperbolic systems with non-unique maximizing measures

Abstract

In this article we study $r$-neutralized local entropy and derive some entropy formulas. For an ergodic hyperbolic measure of a smooth system, we show that the $r$-neutralized local entropy equals the Brin-Katok local entropy plus $r$ times the pointwise dimension of the measure. We further establish the existence of ergodic measures that maximize the $r$-neutralized entropy for certain hyperbolic systems. Moreover, we construct a uniformly hyperbolic system, for which such measures are not unique. Finally, we present some rigidity results related to these ergodic measures.