Equality of essential spectra of certain quasisimilar seminormal operators

Williams, L. R.

doi:10.1090/S0002-9939-1980-0550494-3

Equality of essential spectra of certain quasisimilar seminormal operators
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Proc. Amer. Math. Soc. 78 (1980), 203-209 Request permission

Abstract:

Let A and B be quasisimilar seminormal operators on a separable, infinite dimensional complex Hilbert space. Several conditions which imply that A and B have equal essential spectra are presented. For example, if A and B are both biquasitriangular then A and B have equal essential spectra.

References

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