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arXiv · 2002.00242

Stability and deformation of F-singularities

Alessandro De Stefani·Ilya Smirnov
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Abstract

We study the problem of $\mathfrak{m}$-adic stability of F-singularities, that is, whether the property that a quotient of a local ring $(R,\mathfrak{m})$ by a non-zero divisor $x \in \mathfrak{m}$ has good F-singularities is preserved in a sufficiently small $\mathfrak{m}$-adic neighborhood of $x$. We show that $\mathfrak{m}$-adic stability holds for F-rationality in full generality, and for F-injectivity, F-purity and strong F-regularity under certain assumptions. We show that strong F-regularity and F-purity are not stable in general. Moreover, we exhibit strong connections between stability and deformation phenomena, which hold in great generality.

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Alessandro De Stefani, Ilya Smirnov. 2020-02-01. Stability and deformation of F-singularities. https://arxiv.org/abs/2002.00242

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