English

On the support of measures of large entropy for polynomial-like maps

Dynamical Systems 2024-09-04 v1 Complex Variables

Abstract

Let ff be a polynomial-like map with dominant topological degree dt2d_t\geq 2 and let dk1<dtd_{k-1}<d_t be its dynamical degree of order k1k-1. We show that the support of every ergodic measure whose measure-theoretic entropy is strictly larger than logdk1dt\log \sqrt{d_{k-1} d_t} is supported on the Julia set, i.e., the support of the unique measure of maximal entropy μ\mu. The proof is based on the exponential speed of convergence of the measures dtn(fn)δad_t^{-n}(f^n)^*\delta_a towards μ\mu, which is valid for a generic point aa and with a controlled error bound depending on aa. Our proof also gives a new proof of the same statement in the setting of endomorphisms of Pk(C)\mathbb P^k(\mathbb C) - a result due to de Th\'elin and Dinh - which does not rely on the existence of a Green current.

Keywords

Cite

@article{arxiv.2409.02039,
  title  = {On the support of measures of large entropy for polynomial-like maps},
  author = {Sardor Bazarbaev and Fabrizio Bianchi and Karim Rakhimov},
  journal= {arXiv preprint arXiv:2409.02039},
  year   = {2024}
}