✦ LIBER ✦

On Classes of non-Hyponormal Operators

✍ Scribed by S. M. Patel

Publisher: John Wiley and Sons
Year: 1976
Tongue: English
Weight: 230 KB
Volume: 73
Category: Article
ISSN: 0025-584X
DOI: 10.1002/mana.19760730111

No coin nor oath required. For personal study only.

✦ Synopsis

T . Clearly, for such operators, T*kTk= (T*T)k for all k z 2 . This fact provides a motivation to generalize the class of quasi-normal operators as follows: An operator T is defined to be of class

Obviously ( M ; 2 ) contains hyponormal operators. However, we shall show that the class ( M ; k ) , k > 2 , does not include all hyponormal operators. Therefore the thrust of the conclusions that we obtain will be to show that the class ( M ; k), k -2 , possesses some properties distinct from those of the class of hyponormal operators.

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