English

Canonically Codable Points and Irreducible Codings

Dynamical Systems 2019-04-24 v2

Abstract

MM is a cpt. Riemannian manifold without boundary, fDiff1+β(M)f\in\mathrm{Diff}^{1+\beta}(M). In [Sarig13], for all χ>0\chi>0, for every small enough ϵ>0\epsilon>0, Sarig had first constructed a coding π^:Σ^M\widehat{\pi}:\widehat{\Sigma}\rightarrow M which covers the set of all Lyapunov regular χ\chi-hyperbolic points when dimM=2\mathrm{dim}M=2, where Σ^\widehat{\Sigma} is a topological Markov shift over a locally-finite and countable directed graph. π^\widehat{\pi} is H\"older continuous, and is finite-to-one on Σ^#:={uΣ^:v,w s.t. #{i0:ui=v}=,#{i0:ui=w}=}\widehat{\Sigma}^\#:=\{\underline{u}\in\widehat{\Sigma}:\exists v,w\text{ s.t. }\#\{i\geq0:u_i=v\}=\infty, \#\{i\leq0:u_i=w\}=\infty\}; and π^[Σ^#]{Lyapunov regular and temperable χ-hyperbolic points}\widehat{\pi}[\widehat{\Sigma}^\#]\supseteq \{\text{Lyapunov regular and temperable }\chi\text{-hyperbolic points}\}. We later extended Sarig's result for the case dimM2\mathrm{dim}M\geq2 in [BO18]. In this work, we offer an improved construction for [BO18] such that (ϵ>0\forall\epsilon>0 small enough) we could identify canonically the set π^[Σ^#]\widehat{\pi}[\widehat{\Sigma}^\#]. We introduce the notions of χ\chi-summable, and ϵ\epsilon-weakly temperable points. In [BCS], the authors show that for each homoclinic class of a periodic hyperbolic point pp, there exists a maximal irreducible component Σ~Σ^\widetilde{\Sigma}\subseteq\widehat{\Sigma} s.t. all invariant ergodic probability χ\chi-hyperbolic measures which are carried by the homoclinic class of pp can be lifted to Σ~\widetilde{\Sigma}. We use their construction in the context of ergodic homoclinic classes, to show the stronger claim, π^[Σ~Σ^#]=H(p)\widehat{\pi}[\widetilde{\Sigma}\cap\widehat{\Sigma}^\#]=H(p) modulo all conservative (possibly infinite) measures (dimM2\mathrm{dim}M\geq2); where H(p)H(p) is the ergodic homoclinic class of pp, as defined in [RHRHTU11], with the (canonically identified) recurrently-codable points replacing the Lyapunov regular points in the definition in [RHRHTU11].

Keywords

Cite

@article{arxiv.1904.01391,
  title  = {Canonically Codable Points and Irreducible Codings},
  author = {Snir Ben Ovadia},
  journal= {arXiv preprint arXiv:1904.01391},
  year   = {2019}
}

Comments

A few typos corrected, clarified abstract

R2 v1 2026-06-23T08:26:47.949Z