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arXiv · 1101.3009

On $q$-normal operators and quantum complex plane

Jaka Cimpric·Yurii Savchuk·Konrad Schmüdgen
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Abstract

For $q>0$ let $\cA$ denote the unital $\ast$-algebra with generator $x$ and defining relation $xx^\ast=qxx^\ast$. Based on this algebra we study $q$-normal operators, the complex $q$-moment problem, positive elements and sums of squares.

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Jaka Cimpric, Yurii Savchuk, Konrad Schmüdgen. 2011-01-20. On $q$-normal operators and quantum complex plane. https://doi.org/10.1090/s0002-9947-2013-05733-9

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