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arXiv · 0710.1521

Algebraic quantum permutation groups

Julien Bichon
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Abstract

We discuss some algebraic aspects of quantum permutation groups, working over arbitrary fields. If $K$ is any characteristic zero field, we show that there exists a universal cosemisimple Hopf algebra coacting on the diagonal algebra $K^n$: this is a refinement of Wang's universality theorem for the (compact) quantum permutation group. We also prove a structural result for Hopf algebras having a non-ergodic coaction on the diagonal algebra $K^n$, on which we determine the possible group gradings when $K$ is algebraically closed and has characteristic zero.

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Julien Bichon. 2007-10-08. Algebraic quantum permutation groups. https://arxiv.org/abs/0710.1521

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