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arXiv · 1902.04847

Noncommutative cyclic isolated singularities

Kenneth Chan·Alexander Young·James Zhang
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Abstract

The question of whether a noncommutative graded quotient singularity $A^G$ is isolated depends on a subtle invariant of the $G$-action on $A$, called the pertinency. We prove a partial dichotomy theorem for isolatedness, which applies to a family of noncommutative quotient singularities arising from a graded cyclic action on the $(-1)$-skew polynomial ring. Our results generalize and extend some results of Bao, He and the third-named author and results of Gaddis, Kirkman, Moore and Won.

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Kenneth Chan, Alexander Young, James Zhang. 2019-02-13. Noncommutative cyclic isolated singularities. https://arxiv.org/abs/1902.04847

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