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arXiv · 1812.06343

On C*-completions of discrete quantum group rings

Martijn Caspers·Adam Skalski
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Abstract

We discuss just infiniteness of C*-algebras associated to discrete quantum groups and relate it to the C*-uniqueness of the quantum groups in question, i.e. to the uniqueness of a C*-completion of the underlying Hopf *-algebra. It is shown that duals of q-deformations of simply connected semisimple compact Lie groups are never C*-unique. On the other hand we present an example of a discrete quantum group which is not locally finite and yet is C*-unique.

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Martijn Caspers, Adam Skalski. 2018-12-15. On C*-completions of discrete quantum group rings. https://doi.org/10.1112/blms.12267

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