Essential norms of composition operators between Bloch type spaces in the polydisk

摘要

In 2010, Ruhan Zhao obtained the essential norms of composition operators between Bloch type spaces in the disk by the nth power of the induced analytic function. This paper will generalize Zhao's results to the polydisk. Unlike the case of the composition operators on the unit disk, the essential norms are different for the cases p∈(0,1) and p ≥ 1.