Korean J. Math. Vol. 23 No. 4 (2015) pp.601-605
DOI: https://doi.org/10.11568/kjm.2015.23.4.601

A note on spectral continuity

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Published: Dec 30, 2015
Keywords:
spectral continuity, biquasitriangular
Mathematics Subject Classification:
47A10, 47A53, 47B20

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In Ho Jeon
Department of Mathematics Education Seoul National University of Education Seoul 137-742, Korea
In Hyoun Kim
Department of Mathematics Incheon National University Incheon 406-772, Korea

Abstract

In the present note, provided $T\in\mathscr{L(H)}$ is biquasitriangular and Browder's theorem hold for $T$, we show that the spectrum $\sigma$ is continuous at $T$ if and only if the essential spectrum $\sigma_{e}$ is continuous at $T$.


Article Details

Supporting Agencies

This work was supported by the Incheon National University Research Grant in 2013

References

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