2019/05/22 by Liu, Kairan
#Dynamical Systems (math.DS) #FOS: Mathematics
paper · doi:10.48550/arxiv.1905.08934
The notion of Δ-weakly mixing subsets is introduced for countable torsion-free discrete group actions. It is shown that for a finitely generated torsion-free discrete nilpotent group action, positive topological entropy implies the existence of Δ-weakly mixing subsets, and while there exists a finitely generated torsion-free discrete solvable group action which has positive topological entropy but without any Δ-weakly mixing subsets.