Essential spectra of quasisimilar
-quasihyponormal operators
- An-Hyun Kim1Email author and
- In Hyoun Kim2
https://doi.org/10.1155/JIA/2006/72641
© A.-H. Kim and I. H. Kim 2006
Received: 1 July 2005
Accepted: 20 September 2005
Published: 20 April 2006
Abstract
It is shown that if
is an
upper-triangular operator matrix acting on the Hilbert space
and if
denotes the essential spectrum, then the passage from
to
is accomplished by removing certain open subsets of
from the former. Using this result we establish that quasisimilar
-quasihyponormal operators have equal spectra and essential spectra.
Keywords
Authors’ Affiliations
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