Weak Hyponomal Composition Operators Induced by a Tree

- Journal title : Kyungpook mathematical journal
- Volume 50, Issue 1, 2010, pp.89-100
- Publisher : Department of Mathematics, Kyungpook National University
- DOI : 10.5666/KMJ.2010.50.1.089

Title & Authors

Weak Hyponomal Composition Operators Induced by a Tree

Lee, Mi-Ryeong; Ahn, Hyo-Gun;

Lee, Mi-Ryeong; Ahn, Hyo-Gun;

Abstract

Let g = (V, E, ) be a weighted directed tree, where V is a vertex set, E is an edge set, and is -finite measure on V. The tree g induces a composition operator C on the Hilbert space (V). Hand-type directed trees are defined and characterized the weak hyponormalities of such C in this note. Also some additional related properties are discussed. In addition, some examples related to directed hand-type trees are provided to separate classes of weak-hyponormal operators.

Keywords

directed tree;composition operator;p-hyponormal;p-paranormal;

Language

English

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