English

Smoothness of Markov Partitions for Expanding Toral Endomorphisms

Dynamical Systems 2026-04-02 v1

Abstract

We show that an expanding toral endomorphism in dimension 2 admits a smooth (in fact linear) Markov partition if and only if some power of the corresponding integer matrix is diagonalizable with integer eigenvalues. We exhibit examples of qualitatively different smoothness behavior, and highlight the existence of a hybrid type of smoothness in dimension 2. For dimension d, we show that expanding toral endomorphisms satisfying the eigenvalue condition above admit a linear Markov partition. Finally, we provide an estimate on the Hausdorff dimension of the boundary of a Markov partition using techniques from symbolic dynamics.

Keywords

Cite

@article{arxiv.2604.00257,
  title  = {Smoothness of Markov Partitions for Expanding Toral Endomorphisms},
  author = {Chayce Hughes and Huub de Jong},
  journal= {arXiv preprint arXiv:2604.00257},
  year   = {2026}
}