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arXiv · 1109.0236

Strictification of weakly equivariant Hopf algebras

Jennifer Maier·Thomas Nikolaus·Christoph Schweigert
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Abstract

A weakly equivariant Hopf algebra is a Hopf algebra A with an action of a finite group G up to inner automorphisms. We show that each weakly equivariant Hopf algebra can be replaced by a Morita equivalent algebra B with a strict action of G and with a coalgebra structure that leads to a tensor equivalent representation category. However, the coproduct of this strictification cannot, in general, be chosen to be unital, so that a strictification of the G-action can only be found on a weak Hopf algebra B.

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Jennifer Maier, Thomas Nikolaus, Christoph Schweigert. 2011-09-01. Strictification of weakly equivariant Hopf algebras. https://arxiv.org/abs/1109.0236

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