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arXiv · 2301.13423

Analysis for idempotent states on quantum permutation groups

J. P. McCarthy
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Abstract

Woronowicz proved the existence of the Haar state for compact quantum groups under a separability assumption later removed by Van Daele in a new existence proof. A minor adaptation of Van Daele's proof yields an idempotent state in any non-empty weak*-compact convolution-closed convex subset of the state space. Such subsets, and their associated idempotent states, are studied in the case of quantum permutation groups.

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J. P. McCarthy. 2023-01-31. Analysis for idempotent states on quantum permutation groups. https://arxiv.org/abs/2301.13423

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