A characterization of the Browder spectrum

Author:
Norberto Salinas

Journal:
Proc. Amer. Math. Soc. **38** (1973), 369-373

MSC:
Primary 47A55

DOI:
https://doi.org/10.1090/S0002-9939-1973-0313852-4

MathSciNet review:
0313852

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Abstract: Several different notions of essential spectra are known. This paper is devoted to giving an equivalent definition of the *Browder* essential spectrum for bounded operators on Hilbert space. Also, it is shown that the set of all operators with essentially disconnected spectrum is a uniformly dense set.

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9939-1973-0313852-4

Keywords:
Compression to subspaces of finite codimension,
polynomial hull of the Browder spectrum

Article copyright:
© Copyright 1973
American Mathematical Society