English

Lowering topological entropy over subsets

Dynamical Systems 2011-07-06 v2 General Topology

Abstract

Let (X,T)(X, T) be a topological dynamical system (TDS), and h(T,K)h (T, K) the topological entropy of a subset KK of XX. (X,T)(X, T) is {\it lowerable} if for each 0hh(T,X)0\le h\le h (T, X) there is a non-empty compact subset with entropy hh; is {\it hereditarily lowerable} if each non-empty compact subset is lowerable; is {\it hereditarily uniformly lowerable} if for each non-empty compact subset KK and each 0hh(T,K)0\le h\le h (T, K) there is a non-empty compact subset KhKK_h\subseteq K with h(T,Kh)=hh (T, K_h)= h and KhK_h has at most one limit point. It is shown that each TDS with finite entropy is lowerable, and that a TDS (X,T)(X, T) is hereditarily uniformly lowerable if and only if it is asymptotically hh-expansive.

Keywords

Cite

@article{arxiv.0811.4230,
  title  = {Lowering topological entropy over subsets},
  author = {Wen Huang and Xiangdong Ye and Guohua Zhang},
  journal= {arXiv preprint arXiv:0811.4230},
  year   = {2011}
}

Comments

All comments are welcome. Ergodic Theory and Dynamical Systems, to appear

R2 v1 2026-06-21T11:45:24.091Z