Weyl Type Theorems for Unbounded Hyponormal Operators

If T is an unbounded hyponormal operator on an infinite dimensional complex Hilbert space H with rho(T) not equal phi, then it is shown that T satisfies Weyl's theorem, generalized Weyl's theorem, Browder's theorem and generalized Browder's theorem. The equivalence of generalized Weyl's theorem with generalized Browder's theorem, property (gw) with property (gb) and property (w) with property (b) have also been established. It is also shown that a-Browder's theorem holds for T as well as its adjoint T*.