Bounded point evaluations for cyclic operators and local spectra

Bourhim, A.; Chidume, C.; Zerouali, E.

doi:10.1090/S0002-9939-01-06102-0

Bounded point evaluations for cyclic operators and local spectra
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by A. Bourhim, C. E. Chidume and E. H. Zerouali PDF

Proc. Amer. Math. Soc. 130 (2002), 543-548 Request permission

Abstract:

In this paper we study the concept of bounded point evaluations for cyclic operators. We give a negative answer to a question of L.R. Williams, Dynamic Systems and Applications 3 (1994), 103-112. Furthermore, we generalize some results of Williams and give a simple proof that nonnormal hyponormal weighted shifts have fat local spectra.

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