Bishop’s property, Weyl’s Theorem and Riesz idempotent
Keywords:
Weyl’s Theorem, Isoloid operators, Bishop’s property, Riesz idempotent.Abstract
Important fundamental and spectral properties of the classes of quasi n-normal and k-quasi n-normal operators defined on a separable complex Hilbert space constitute the aim of the present paper. We prove that the considered operators satisfy Bishop’s property (β) and that are polaroid, subscalar and decomposable. It’s also proved that a k-quasi n- normal operator has a non trivial invariant subspace and Weyl’s theorem holds for this operator. Other results related to the Riesz idempotent of elements of these classes are also established.
References
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