Wandering subspaces and the Beurling type theorem, III

Abstract

Let H²(D²) be the Hardy space over the bidisk. Let {φ_n(z)}_{n ≥ 0} and {ψ_n(w)}_{n ≥ 0} be sequences of one variable inner functions satisfying some additinal conditions. Associated with them, we have a Rudin type invariant subspace M of H²(D²). We study the Beurling type theorem for the fringe operator F_w on M $¥ominus$ zM.