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arXiv · 0906.2362

A New Characterisation of Idempotent States on Finite and Compact Quantum Groups

Uwe Franz·Adam Skalski
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Abstract

We show that idempotent states on finite quantum groups correspond to pre-subgroups in the sense of Baaj, Blanchard, and Skandalis. It follows that the lattices formed by the idempotent states on a finite quantum group and by its coidalgebras are isomorphic. We show furthermore that these lattices are also isomorphic for compact quantum groups, if one restricts to expected coidalgebras.

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Uwe Franz, Adam Skalski. 2009-06-12. A New Characterisation of Idempotent States on Finite and Compact Quantum Groups. https://doi.org/10.1016/j.crma.2009.06.015

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