[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.4134/JKMS.2007.44.1.025

ON A CLASS OF OPERATORS RELATED TO PARANORMAL OPERATORS

Lee, Mi-Young (Department of Mathematics College of Natural Science Kyungpook National University)
Lee, Sang-Hun (Department of Mathematics College of Natural Science Kyungpook National University)

Publication Information

Journal of the Korean Mathematical Society / v.44, no.1, 2007 , pp. 25-34 More about this Journal

Abstract

An operator $T{\in}L(H)$ is said to be p-paranormal if $\parallel{\mid}T\mid^pU{\mid}T\mid^px{\parallel}x\parallel\geq\parallel{\mid}T\mid^px\parallel^2$ for all $x{\in}H$ and p > 0, where $T=U{\mid}T\mid$ is the polar decomposition of T. It is easy that every 1-paranormal operator is paranormal, and every p-paranormal operator is paranormal for 0 < p < 1. In this note, we discuss some properties for p-paranormal operators.

Keywords

paranormal; p-paranormal; polar decomposition;

Citations & Related Records

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