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

Main Article Content

In Ho Jeon
In Hyoun Kim


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 $T$.

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Supporting Agencies

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


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