Hostname: page-component-76fb5796d-qxdb6 Total loading time: 0 Render date: 2024-04-28T18:30:32.879Z Has data issue: false hasContentIssue false

ON WEYL AND BROWDER SPECTRA OF TENSOR PRODUCTS

Published online by Cambridge University Press:  01 May 2008

C. S. KUBRUSLY
Affiliation:
Catholic University of Rio de Janeiro, 22453-900, Rio de Janeiro, RJ, Brazil e-mail: carlos@ele.puc-rio.br
B. P. DUGGAL
Affiliation:
8 Redwood Grove, Northfields Avenue, Ealing, London W5 4SZ, England, U.K. e-mail: bpduggal@yahoo.co.uk
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Let A and B be Hilbert space operators. In this paper we explore the structure of parts of the spectrum of the tensor product AB, and conclude some properties that follow from such a structure. We give conditions on A and B ensuring that σw(AB) =σw(A)ċσ(B) ∪ σ(A)ċσw(B), where σ(ċ) and σw(ċ) stand for the spectrum and Weyl spectrum, respectively. We also investigate the problem of transferring Weyl and Browder's theorems from A and B to their tensor product AB.

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 2008

References

REFERENCES

1.Berberian, S. K.An extension of Weyl's theorem to a class of not necessarily normal operators, Michigan Math. J. 16 (1969), 273279.CrossRefGoogle Scholar
2.Berberian, S. K.The Weyl spectrum of an operator, Indiana Univ. Math. J. 20 (1971), 529544.CrossRefGoogle Scholar
3.Brown, A. and Pearcy, C.Spectra of tensor products of operators, Proc. Amer. Math. Soc. 17 (1966), 162166.CrossRefGoogle Scholar
4.Duggal, B. P., Browder–Weyl theorems, tensor products and multiplications, pre-print (2006).Google Scholar
5.Duggal, B. P. and Kubrusly, C. S.Weyl's theorem for direct sums, Studia Sci. Math. Hungar. 44 (2007), 275290.Google Scholar
6.Harte, R. and Lee, W. Y.Another note on Weyl's theorem, Trans. Amer. Math. Soc. 349 (1997), 21152124.CrossRefGoogle Scholar
7.Ichinose, T.Spectral properties of linear operators I, Trans. Amer. Math. Soc. 235 (1978), 75113.CrossRefGoogle Scholar
8.Kubrusly, C. S.Elements of operator theory, (Birkhäuser, 2001).CrossRefGoogle Scholar
9.Kubrusly, C. S.A concise introduction to tensor product, Far East J. Math. Sci. 22 (2006), 137174.Google Scholar
10.Song, Y.-M. and Kim, A.-H., Weyl's theorem for tensor products, Glasgow. Math. J. 46 (2004), 301304.CrossRefGoogle Scholar
11.Weidmann, J.Linear operators in Hilbert spaces, (Springer, Verlag, 1980).CrossRefGoogle Scholar