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arXiv · 1606.08428

Rigidity of down-up algebras with respect to finite group coactions

J. Chen·E. Kirkman·J. J. Zhang
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Abstract

If a nontrivial finite group coacts on a graded noetherian down-up algebra $A$ inner faithfully and homogeneously, then the fixed subring is not isomorphic to $A$. Therefore graded noetherian down-up algebras are rigid with respect to finite group coactions, in the sense of Alev-Polo. An example is given to show that this rigidity under group coactions does not have all the same consequences as the rigidity under group actions.

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J. Chen, E. Kirkman, J. J. Zhang. 2016-06-27. Rigidity of down-up algebras with respect to finite group coactions. https://arxiv.org/abs/1606.08428

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