Homomorphisms from aperiodic subshifts to subshifts with the finite extension property

Abstract

Given a countable group $G$ and two subshifts $X$ and $Y$ over $G$, a continuous, shift-commuting map $\varphi :X\to Y$ is called a homomorphism. Our main result states that if every finitely generated subgroup of $G$ has polynomial growth, $X$ is aperiodic, and $Y$ has the finite extension property (FEP), then there exists a homomorphism $\varphi :X\to Y$. By combining this theorem with a previous result of Bland, we obtain that if the same conditions hold, and if additionally the topological entropy of $X$ is less than the topological entropy of $Y$ and $Y$ has no global period, then $X$ embeds into $Y$. We also establish some facts about subshifts with the FEP that may be of independent interest.

References in corpus (5)

• Subsystem entropies of shifts of finite type and sofic shifts on countable amenable groups
• Expansive actions with specification of sofic groups, strong topological Markov property, and surjunctivity
• An embedding theorem for subshifts over amenable groups with the comparison property
• Ubiquity of entropies of intermediate factors
• An embedding theorem for multidimensional subshifts