A characterization of the Browder spectrum

Salinas, Norberto

doi:10.1090/S0002-9939-1973-0313852-4

A characterization of the Browder spectrum
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Proc. Amer. Math. Soc. 38 (1973), 369-373 Request permission

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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