Weyl Type Theorems for Unbounded Hyponormal Operators

• Journal title : Kyungpook mathematical journal
• Volume 55, Issue 3,  2015, pp.531-540
• Publisher : Department of Mathematics, Kyungpook National University
• DOI : 10.5666/KMJ.2015.55.3.531
Title & Authors
Weyl Type Theorems for Unbounded Hyponormal Operators

Abstract
If T is an unbounded hyponormal operator on an infinite dimensional complex Hilbert space H with $\small{{\rho}(T){\neq}{\phi}}$, 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 $\small{T^*}$.
Keywords
Unbounded hyponormal operators;Weyl-type theorems;property (w);property (b);
Language
English
Cited by
1.
Weyl type theorems for unbounded class- $$\mathcal {A}$$ A operators, Afrika Matematika, 2017, 28, 5-6, 745
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