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arXiv · 2304.14711

Non-commutative resolutions of linearly reductive quotient singularities

Christian Liedtke·Takehiko Yasuda
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Abstract

We prove existence of non-commutative crepant resolutions (in the sense of van den Bergh) of quotient singularities by finite and linearly reductive group schemes in positive characteristic. In dimension two, we relate these to resolutions of singularities provided by G-Hilbert schemes and F-blowups. As an application, we establish and recover results concerning resolutions for toric singularities, as well as canonical, log terminal, and F-regular singularities in dimension 2.

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Christian Liedtke, Takehiko Yasuda. 2023-04-28. Non-commutative resolutions of linearly reductive quotient singularities. https://doi.org/10.1093/qmath/haae033

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