Distortion and the automorphism group of a shift

Autor: Bryna Kra, John Franks, Van Cyr, Samuel Petite
Přispěvatelé: Bucknell University Departement of Mathematics, Umicore Coating Services, Department of Mathematics, Northwestern University, Northwestern University, Laboratoire Amiénois de Mathématique Fondamentale et Appliquée - UMR CNRS 7352 (LAMFA), Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)
Rok vydání: 2018
Předmět:
Zdroj: Journal of modern dynamics
Journal of modern dynamics, American Institute of Mathematical Sciences, 2018, 13 (1), pp.147-161. ⟨10.3934/jmd.2018015⟩
ISSN: 1930-532X
1930-5311
DOI: 10.3934/jmd.2018015
Popis: The set of automorphisms of a one-dimensional subshift \begin{document} $(X, σ)$ \end{document} forms a countable, but often very complicated, group. For zero entropy shifts, it has recently been shown that the automorphism group is more tame. We provide the first examples of countable groups that cannot embed into the automorphism group of any zero entropy subshift. In particular, we show that the Baumslag-Solitar groups \begin{document} ${\rm BS}(1,n)$ \end{document} and all other groups that contain exponentially distorted elements cannot embed into \begin{document} ${\rm Aut}(X)$ \end{document} when \begin{document} $h_{{\rm top}}(X) = 0$ \end{document} . We further show that distortion in nilpotent groups gives a nontrivial obstruction to embedding such a group in any low complexity shift.
Databáze: OpenAIRE