Block diagonalization in Banach algebras
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- by Robin Harte PDF
- Proc. Amer. Math. Soc. 129 (2001), 181-190 Request permission
Abstract:
“Reduction" of linear operators is effected by commuting projections; the spectrum of the operator is then the union of the spectra of its range and null space restrictions. Disjointness of these partial spectra implies that the projection “double commutes" with the operator, which in turn can be recognised as a curious kind of “exactness". Variants of this exactness correspond to various kinds of disjointness between the partial spectra.References
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Additional Information
- Robin Harte
- Affiliation: School of Mathematics, Trinity College, Dublin 2, Ireland
- Email: rharte@maths.tcd.ie
- Received by editor(s): December 15, 1997
- Received by editor(s) in revised form: March 10, 1998, October 6, 1998, and March 31, 1999
- Published electronically: August 17, 2000
- Communicated by: David R. Larson
- © Copyright 2000 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 129 (2001), 181-190
- MSC (1991): Primary 47A13; Secondary 15A21, 15A18
- DOI: https://doi.org/10.1090/S0002-9939-00-05884-6
- MathSciNet review: 1784022