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arXiv · 1904.07755

A transformation rule for natural multiplicities

Jack Jeffries·Ilya Smirnov
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Abstract

For multiplicities arising from a family of ideals we provide a general approach to transformation rules for a ring extension étale in codimension one. Our result can be applied to bound the size of the local étale fundamental group of a singularity in terms of F-signature, recovering a recent result of Carvajal-Rojas, Schwede, and Tucker, and differential signature, providing the first characteristic-free effective bound.

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Jack Jeffries, Ilya Smirnov. 2020-02-25. A transformation rule for natural multiplicities. https://arxiv.org/abs/1904.07755

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