2017/10/10 by Cohen, David Bruce
#20F65 #37B50 #Dynamical Systems (math.DS) #FOS: Mathematics #Group Theory (math.GR)
paper · doi:10.48550/arxiv.1710.03707
Let A be a finite set and G a group. A closed subset X of AG is called a subshift if the action of G on AG preserves X. If K is a closed subset of AG such that membership in K is determined by looking at a fixed finite set of coordinates, and X is the intersection of all translates of K under the action of G, then X is called a subshift of finite type (SFT). If an SFT is nonempty and contains no finite G-orbits, it is said to be weakly aperiodic. A virtually cyclic group has no weakly aperiodic SFT, and Carroll and Penland have conjectured that a group with no weakly aperiodic SFT must be virtually cyclic. Answering a question of Jeandel, we show that lamplighters always admit weakly aperiodic SFTs.