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arXiv · 2410.15291

Liftings of ideals in positive characteristic to those in characteristic zero : Low dimension

Shihoko Ishii
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Abstract

We study a pair consisting of a smooth variety over a field of positive characteristic and a multi-ideal with a real exponent. We prove the finiteness of the set of minimal log discrepancies for a fixed exponent if the dimension is less than or equal to three. We also prove that the set of log canonical thresholds (lct for short) of ideals on a smooth variety in positive characteristic is contained in the set of lct's of ideals on a smooth variety over C, assuming the dimension is less than or equal to three. Under the same dimension assumption, it follows that the accumulation points of log canonical thresholds are rational. Our proofs also show the same statements for the higher dimensional case if all such pairs admit log resolutions by a composite of blow-ups by smooth centers.

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Shihoko Ishii. 2024-10-20. Liftings of ideals in positive characteristic to those in characteristic zero : Low dimension. https://arxiv.org/abs/2410.15291

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