# k-TH ROOTS OF p-HYPONORMAL OPERATORS

• DUGGAL BHAGWATI P. (REDWOOD GROVE) ;
• JEON IN Ho (DEPARTMENT OF MATHMATHICS, EWHA WOMEN'S UNIVERSITY) ;
• KO AND EUNGIL (DEPARTMENT OF MATHMATHICS, EWHA WOMEN'S UNIVERSITY)
• Published : 2005.08.01

#### 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.

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