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arXiv · 2501.12091

F-Splittings of seminormal monoid algebras

Milena Hering·Kevin Tucker
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Abstract

We compute a number of invariants of singularities defined via the Frobenius morphism for seminormal affine toric varieties over fields of characteristic p > 0. Our main technical tool is a combinatorial description of the potential splittings of iterates of Frobenius for seminormal monoid algebras. This allows us to give an easy formula for the F-splitting ratio of such rings as well as to compute the ideals stable under the Cartier algebra, including the test ideal.

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Milena Hering, Kevin Tucker. 2025-01-21. F-Splittings of seminormal monoid algebras. https://arxiv.org/abs/2501.12091

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