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arXiv · 1004.1377

A note on discreteness of $F$-jumping numbers

Karl Schwede
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Abstract

Suppose that $R$ is a ring essentially of finite type over a perfect field of characteristic $p > 0$ and that $a \subseteq R$ is an ideal. We prove that the set of $F$-jumping numbers of $τ_b(R; a^t)$ has no limit points under the assumption that $R$ is normal and $Q$-Gorenstein -- we do \emph{not} assume that the $Q$-Gorenstein index is not divisible by $p$. Furthermore, we also show that the $F$-jumping numbers of $τ_b(R; Δ, a^t)$ are discrete under the more general assumption that $K_R + Δ$ is $\bR$-Cartier.

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Karl Schwede. 2010-12-11. A note on discreteness of $F$-jumping numbers. https://arxiv.org/abs/1004.1377

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