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arXiv · 2305.05905

Crepant resolution of $\mathbb{A}^4/A_4$ in characteristic 2

Linghu Fan
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Abstract

In this paper, we construct a crepant resolution for the quotient singularity $\mathbb{A}^4/A_4$ in characteristic 2, where $A_4$ is the alternating group of degree 4 with permutation action on $\mathbb{A}^4$. By computing the Euler number of the crepant resolution, we obtain a new counterexample to an analogous statement of McKay correspondence in positive characteristic.

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Linghu Fan. 2023-05-10. Crepant resolution of $\mathbb{A}^4/A_4$ in characteristic 2. https://doi.org/10.3792/pjaa.99.014

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