Some consequences of shadowing and entropy-expansiveness
Noriaki Kawaguchi
TL;DR
This work analyzes how shadowing and $h$-expansiveness constrain uniformly rigid behavior on compact metric spaces. It proves that any non-empty uniformly rigid subset under such a map $f$ must be zero-dimensional, which in turn forces the periodic-point set $Per(f)$ to be zero-dimensional when non-empty. The key method is a contradiction argument built from $\,\delta$-pseudo orbits and a symbolic shift factor, leading to a violation of $h$-expansiveness unless the uniformly rigid set is totally disconnected. The paper clarifies the interplay between rigidity, shadowing, and entropy-like constraints, and it provides several illustrative examples (Cantor-set identities, odometers, and shifts) highlighting the scope and limits of the results.
Abstract
We show that if a continuous self-map of a compact metric space is h-expansive and satisfies the shadowing property, then every non-empty uniformly rigid subset is zero-dimensional, and hence the set of periodic points is also zero-dimensional if it is not empty.
