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Proceedings of the American Mathematical Society
Proceedings of the American Mathematical Society
ISSN 1088-6826(e) ISSN 0002-9939(p)

     

On the Helton class of -hyponormal operators

Author(s): Yoenha Kim; Eungil Ko; Ji Eun Lee
Journal: Proc. Amer. Math. Soc. 135 (2007), 2113-2120.
MSC (2000): Primary 47B20; Secondary 47A10
Posted: February 28, 2007
MathSciNet review: 2299488
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Abstract | References | Similar articles | Additional information

Abstract: In this paper we show that the Helton class of -hyponormal operators has scalar extensions. As a corollary we get that each operator in the Helton class of $ p$-hyponormal operators has a nontrivial invariant subspace if its spectrum has its interior in the plane.


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Additional Information:

Yoenha Kim
Affiliation: Department of Mathematics, Ewha Women's University, Seoul 120-750, Korea
Email: yoenha@ewhain.net

Eungil Ko
Affiliation: Department of Mathematics, Ewha Women's University, Seoul 120-750, Korea
Email: eiko@ewha.ac.kr

Ji Eun Lee
Affiliation: Department of Mathematics, Ewha Women's University, Seoul 120-750, Korea
Email: jieun7@ewhain.net

DOI: 10.1090/S0002-9939-07-08708-4
PII: S 0002-9939(07)08708-4
Received by editor(s): December 14, 2004
Received by editor(s) in revised form: March 13, 2006
Posted: February 28, 2007
Additional Notes: This work was supported by a grant (R14-2003-006-01000-0) from the Korea Research Foundation.
Communicated by: Joseph A. Ball
Copyright of article: Copyright 2007, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.




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