English

Equivariant embedding of finite-dimensional dynamical systems

Dynamical Systems 2024-07-03 v4 General Topology

Abstract

We prove an equivariant version of the classical Menger-Nobeling theorem regarding topological embeddings: Whenever a group GG acts on a finite-dimensional compact metric space XX, a generic continuous equivariant function from XX into ([0,1]r)G([0,1]^r)^G is a topological embedding, provided that for every positive integer NN the space of points in XX with orbit size at most NN has topological dimension strictly less than rN2\frac{rN}{2}. We emphasize that the result imposes no restrictions whatsoever on the acting group GG (beyond the existence of an action on a finite-dimensional space). Moreover, if GG is finitely generated then there exists a finite subset FGF\subset G so that for a generic continuous map h:X[0,1]rh:X\to [0,1]^{r}, the map hF:X([0,1]r)Fh^{F}:X\to ([0,1]^{r})^{F} given by x(f(gx))gFx\mapsto (f(gx))_{g\in F} is an embedding. This constitutes a generalization of the Takens delay embedding theorem into the topological category.

Keywords

Cite

@article{arxiv.2305.17717,
  title  = {Equivariant embedding of finite-dimensional dynamical systems},
  author = {Yonatan Gutman and Michael Levin and Tom Meyerovitch},
  journal= {arXiv preprint arXiv:2305.17717},
  year   = {2024}
}

Comments

23 pages. Minor corrections to proof of Theorem 1.6

R2 v1 2026-06-28T10:48:41.589Z