English

Sensitivity, proximal extension and higher order almost automorphy

Dynamical Systems 2016-11-09 v2

Abstract

Let (X,T)(X,T) be a topological dynamical system, and F\mathcal{F} be a family of subsets of Z+\mathbb{Z}_+. (X,T)(X,T) is strongly F\mathcal{F}-sensitive, if there is δ>0\delta>0 such that for each non-empty open subset UU, there are x,yUx,y\in U with {nZ+:d(Tnx,Tny)>δ}F\{n\in\mathbb{Z}_+: d(T^nx,T^ny)>\delta\}\in\mathcal{F}. Let Ft\mathcal{F}_t (resp. Fip\mathcal{F}_{ip}, Ffip\mathcal{F}_{fip}) be consisting of thick sets (resp. IP-sets, subsets containing arbitrarily long finite IP-sets). The following Auslander-Yorke's type dichotomy theorems are obtained: (1) a minimal system is either strongly Ffip\mathcal{F}_{fip}-sensitive or an almost one-to-one extension of its \infty-step nilfactor. (2) a minimal system is either strongly Fip\mathcal{F}_{ip}-sensitive or an almost one-to-one extension of its maximal distal factor. (3) a minimal system is either strongly Ft\mathcal{F}_{t}-sensitive or a proximal extension of its maximal distal factor.

Keywords

Cite

@article{arxiv.1605.01119,
  title  = {Sensitivity, proximal extension and higher order almost automorphy},
  author = {Xiangdong Ye and Tao Yu},
  journal= {arXiv preprint arXiv:1605.01119},
  year   = {2016}
}

Comments

24 pages, revised version following referees' reports. To appear in Transactions of the AMS

R2 v1 2026-06-22T13:52:45.775Z