k-TH ROOTS OF p-HYPONORMAL OPERATORS

DUGGAL BHAGWATI P.; JEON IN Ho; KO AND EUNGIL

doi:10.4134/BKMS.2005.42.3.571

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k-TH ROOTS OF p-HYPONORMAL OPERATORS

Journal title : Bulletin of the Korean Mathematical Society
Volume 42, Issue 3, 2005, pp.571-577
Publisher : The Korean Mathematical Society
DOI : 10.4134/BKMS.2005.42.3.571

Title & Authors

k-TH ROOTS OF p-HYPONORMAL OPERATORS
DUGGAL BHAGWATI P.; JEON IN Ho; KO AND EUNGIL;

Abstract

In this paper we prove that if T is a k-th root of a phyponormal operator when T is compact or T ${$^{n}$}$ is normal for some integer n > k, then T is (generalized) scalar, and that if T is a k-th root of a semi-hyponormal operator and have the property ${$\sigma$}$ (T) is contained in an angle < 2 ${$\pi$}$ /k with vertex in the origin, then T is subscalar.

Keywords

k-th roots of p-hyponormal operator;subscalar operator;

Language

English

Cited by

References

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