DOI QR코드

DOI QR Code

SPECTRAL PROPERTIES OF k-QUASI-2-ISOMETRIC OPERATORS

SHEN, JUNKI;ZUO, FEI

  • Received : 2015.07.04
  • Accepted : 2015.07.14
  • Published : 2015.08.31

Abstract

Let T be a bounded linear operator on a complex Hilbert space H. For a positive integer k, an operator T is said to be a k-quasi-2-isometric operator if T∗k(T∗2T2 − 2TT + I)Tk = 0, which is a generalization of 2-isometric operator. In this paper, we consider basic structural properties of k-quasi-2-isometric operators. Moreover, we give some examples of k-quasi-2-isometric operators. Finally, we prove that generalized Weyl’s theorem holds for polynomially k-quasi-2-isometric operators.

Keywords

k-quasi-2-isometric operator;polaroid;generalized Weyl’s theorem.

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