When does the F-signature exist?

Ian M. Aberbach; Florian Enescu

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arXiv · math/0502351

When does the F-signature exist?

Ian M. Aberbach·Florian Enescu

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Abstract

We show that the F-signature of an F-finite local ring R of characteristic p >0 exists when R is either the localization of an $\mathbf{N}$-graded ring at its irrelevant ideal or $\mathbf{Q}$-Gorenstein on its punctured spectrum. This extends results by Huneke, Leuschke, Yao and Singh and proves the existence of the F-signature in the cases where weak F-regularity is known to be equivalent to strong F-regularity.

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Ian M. Aberbach, Florian Enescu. 2005-02-16. When does the F-signature exist?. https://arxiv.org/abs/math/0502351

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