Triangular extension spectrum of weighted shifts
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- by Zhidong Pan PDF
- Proc. Amer. Math. Soc. 126 (1998), 3293-3298 Request permission
Abstract:
A necessary and sufficient condition for a complex number to be in the triangular extension spectrum of a weighted backward shift is obtained. It is shown that the triangular extension spectrum of a weighted backward shift is always a closed annulus when it is not empty. Moreover, for any given closed annulus, there exists a weighted backward shift with the annulus as its triangular extension spectrum.References
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Additional Information
- Zhidong Pan
- Affiliation: Department of Mathematics, Saginaw Valley State University, University Center, Michigan 48710
- Email: pan@tardis.svsu.edu
- Additional Notes: This work was supported in part by a research release time award from Saginaw Valley State University
- Communicated by: Palle E. T. Jorgensen
- © Copyright 1998 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 126 (1998), 3293-3298
- MSC (1991): Primary 47A15, 47A45, 47C05
- DOI: https://doi.org/10.1090/S0002-9939-98-04692-9
- MathSciNet review: 1476383