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arXiv · 1410.1665

On positive definiteness over locally compact quantum groups

Volker Runde·Ami Viselter
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Abstract

The notion of positive-definite functions over locally compact quantum groups was recently introduced and studied by Daws and Salmi. Based on this work, we generalize various well-known results about positive-definite functions over groups to the quantum framework. Among these are theorems on "square roots" of positive-definite functions, comparison of various topologies, positive-definite measures and characterizations of amenability, and the separation property with respect to compact quantum subgroups.

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Volker Runde, Ami Viselter. 2014-10-07. On positive definiteness over locally compact quantum groups. https://doi.org/10.4153/cjm-2015-019-0

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