English

On the representation of measurable and continuous dynamical systems by Lipschitz functions

Dynamical Systems 2026-04-02 v2

Abstract

Two representations theorems are presented: 1. Any Borel action of a second countable locally compact group GG on a standard Borel space XX admits an injective GG-equivariant Borel map into the shift space of 11-Lipschitz functions from GG to the unit interval Lip1(G)Lip_1(G). 2. Any continuous action of Rk\mathbb{R}^k (kNk\in \mathbb{N}) on a metrizable compact space XX admits an injective GG-equivariant continuous map into Lip1(Rk)Lip_1(\mathbb{R}^k) if the fixed point set Fix(X,Rk)Fix(X,\mathbb{R}^k) embeds into [0,1][0,1] and (X,Rk)(X,\mathbb{R}^k) is \textit{weakly locally free}, that is Rk\mathbb{R}^k acts freely outside the fixed point set. The first theorem generalizes a theorem from 1973 by Eberlein for R\mathbb{R}-flows. The second theorem generalizes a Lipschitz refinement of the Bebutov-Kakutani theorem proven by Gutman, Jin and Tsukamoto in 2019.

Keywords

Cite

@article{arxiv.2505.14653,
  title  = {On the representation of measurable and continuous dynamical systems by Lipschitz functions},
  author = {Yonatan Gutman and Qiang Huo},
  journal= {arXiv preprint arXiv:2505.14653},
  year   = {2026}
}