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arXiv · 2603.29104

Regular rings over valuation rings

Shiji Lyu
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Abstract

Bertin (1972) defined regularity for coherent local rings, and Knaf (2004) studied the property for a local ring $A$ essentially finitely presented over a valuation ring $V$. We discuss several properties of this notion of regularity for such $A$, obtaining results parallel to results for regularity of Noetherian local rings. We include classical and modern topics: openness of loci, perfectoid big Cohen--Macaulay algebras, and cotangent complexes. We also give an application to Noetherian rings, showing a version of Kodaira's vanishing theorem in large enough residue characteristics.

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Shiji Lyu. 2026-03-31. Regular rings over valuation rings. https://arxiv.org/abs/2603.29104

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