On the dynamics of subcontinua of a tree
MYKOLA MATVIICHUKGiven a tree map f : T → T , we study the dynamics of subcontinua of T under action of f . In particular, we prove that a subcontinuum of T is either asymptotically periodic or asymptotically degenerate. As an application of this result, we show that zero topological entropy of the system (T, f ) implies zero topological entropy of its functional envelope (endowed with the Hausdorff metric).