# ON RANK ONE PERTURBATIONS OF THE UNILATERAL SHIFT

• Ko, Eung-Il (DEPARTMENT OF MATHEMATICS EWHA WOMEN'S UNIVERSITY) ;
• Lee, Ji-Eun (DEPARTMENT OF MATHEMATICS KYUNG HEE UNIVERSITY, INSTITUTE OF MATHEMATICAL SCIENCES EWHA WOMEN'S UNIVERSITY)
• Published : 2011.01.31

#### Abstract

In this paper we study some properties of rank one perturbations of the unilateral shift operators $T=S+u{\otimes}{\upsilon}$. In particular, we give some criteria for eigenvalues of T. Also we characterize some conditions for T to be hyponormal.

#### Acknowledgement

Supported by : Korea Research Foundation

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