A note on multivariate diam mean equicontinuity and frequent stability
Abstract
Let be a topological dynamical system, given by the action of a is a countable discrete infinite group on a compact metric space . We prove that if is minimal, then it is either diam-mean -equicontinuious or diam-mean -sensitive. Similarly, is either frequently -stable or strongly -spreading. Further, when is abelian (or, more generally, virtually nilpotent), then the following statements are equivalent: is a regular -to-one extension of its maximal equicontinuous factor; is diam-mean -equicontinuious, and not diam mean -equicontinuious; is not diam-mean -sensitive, but diam mean -sensitive; has an essential weakly mean sensitive -tuple but no essential weakly mean sensitive -tuple. This provides a {\em \enquote*{local}} characterisation of -regularity and mean -sensitivity vial weakly mean sensitive tuples. The same result holds when is amenable and satisfies the local Bronstein condition.
Cite
@article{arxiv.2506.23313,
title = {A note on multivariate diam mean equicontinuity and frequent stability},
author = {Lino Haupt and Tobias Jäger and Chunlin Liu},
journal= {arXiv preprint arXiv:2506.23313},
year = {2025}
}