Fedder-type criterion for quasi-F^e-splitting and quasi-F-regularity

2025/05/13 by Yoshikawa, Shou · 1 citation
#Algebraic Geometry (math.AG) #Commutative Algebra (math.AC) #FOS: Mathematics

paper · doi:10.48550/arxiv.2505.09015

Abstract

We study quasi-F^e-split and quasi-F-regular singularities, which generalize Yobuko's quasi-F-splitting. We establish Fedder type criteria that characterize these properties for hypersurfaces. These criteria offer explicit tools for computation and verification. As an application, we construct a counterexample to the inversion of adjunction for quasi-F-regularity and compute the quasi-F-split threshold of the cone over the ordinary cusp.

Citations

• Quasi-F-splittings in birational geometry III
• Quasi-F^e-splittings and quasi-F-regularity
• Quasi-F-splittings in birational geometry

Cited by

• Graded perfectoid rings

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• Quasi-F^e-splittings and quasi-F-regularity
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• Quasi-F-splittings in birational geometry III