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arXiv · 2304.05937

Group coactions on two-dimensional Artin-Schelter regular algebras

Simon Crawford
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Abstract

We describe all possible coactions of finite groups (equivalently, all group gradings) on two-dimensional Artin-Schelter regular algebras. We give necessary and sufficient conditions for the associated Auslander map to be an isomorphism, and determine precisely when the invariant ring for the coaction is Artin-Schelter regular. The proofs of our results are combinatorial and exploit the structure of the McKay quiver associated to the coaction.

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Simon Crawford. 2023-04-12. Group coactions on two-dimensional Artin-Schelter regular algebras. https://arxiv.org/abs/2304.05937

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