INVARIANT SUBSPACES OF THE MULTIPLICATION OPERATOR ON HILBERTFUNCTION SPACES

under some conditions on a Hilbert space H of analytic fuctions on the open unit disc we will show that for every nontrivial invariant subspace M of H, there exists a unique nonconstant immer function φ such that M = @H. This extends ۱.he Beurling s Theorem.

Keywords:

Invariant subspaces , reproducing kernels , inner functions , multipliers.