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arXiv · 1107.6010

Polynomials of almost-normal arguments in $C^*$-algebras

Nikolay Filonov·Ilya Kachkovskiy
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Abstract

The functional calculus for normal elements in $C^*$-algebras is an important tool of analysis. We consider polynomials $p(a,a^*)$ for elements $a$ with small self-commutator norm $\|[a,a^*]\| \le δ$ and show that many properties of the functional calculus are retained modulo an error of order $δ$.

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Nikolay Filonov, Ilya Kachkovskiy. 2012-02-10. Polynomials of almost-normal arguments in $C^*$-algebras. https://arxiv.org/abs/1107.6010

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