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arXiv · 1808.03056

Applications of the Growth Characteristics Induced by the Spectral Distance

Rudi Brits
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Abstract

Let $A$ be a complex unital Banach algebra. Using a connection between the spectral distance and the growth characteristics of a certain entire map into $A$, we derive a generalization of Gelfand's famous Power Boundedness Theorem. Elaborating on these ideas, with the help of a Phragm\'{e}n-Lindel\"{o}f device for subharmonic functions, it is then shown, as the main result, that two normal elements of a $C^*$-algebra are equal if and only if they are quasinilpotent equivalent.

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Rudi Brits. 2018-08-09. Applications of the Growth Characteristics Induced by the Spectral Distance. https://arxiv.org/abs/1808.03056

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