English

A smooth zero-entropy diffeomorphism whose product with itself is loosely Bernoulli

Dynamical Systems 2018-03-07 v1

Abstract

Let MM be a smooth compact connected manifold of dimension d2d\geq 2, possibly with boundary, that admits a smooth effective T2\mathbb{T}^2-action S={Sα,β}(α,β)T2\mathcal{S}=\left\{S_{\alpha,\beta}\right\}_{(\alpha,\beta) \in \mathbb{T}^2} preserving a smooth volume ν\nu, and let B\mathcal{B} be the CC^{\infty} closure of {hSα,βh1  :  hDiff(M,ν),(α,β)T2}\left\{h \circ S_{\alpha,\beta} \circ h^{-1} \;:\;h \in \text{Diff}^{\infty}\left(M,\nu\right), (\alpha,\beta) \in \mathbb{T}^2\right\}. We construct a CC^{\infty} diffeomorphism TBT \in \mathcal{B} with topological entropy 00 such that T×TT \times T is loosely Bernoulli. Moreover, we show that the set of such TBT \in \mathcal{B} contains a dense GδG_{\delta} subset of B\mathcal{B}. The proofs are based on a two-dimensional version of the approximation-by-conjugation method.

Keywords

Cite

@article{arxiv.1803.01926,
  title  = {A smooth zero-entropy diffeomorphism whose product with itself is loosely Bernoulli},
  author = {Marlies Gerber and Philipp Kunde},
  journal= {arXiv preprint arXiv:1803.01926},
  year   = {2018}
}

Comments

52 pages, 8 figures

R2 v1 2026-06-23T00:43:04.130Z