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A Hilbert-Kunz criterion for solid closure in dimension two (characteristic zero)

Holger Brenner
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Abstract

Let I denote a homogeneous R_+-primary ideal in a two-dimensional normal standard-graded domain over an algebraically closed field of characteristic zero. We show that a homogeneous element f belongs to the solid closure I^* if and only if e_{HK}(I) = e_{HK}((I,f)), where e_{HK} denotes the (characteristic zero) Hilbert-Kunz multiplicity of an ideal. This provides a version in characteristic zero of the well-known Hilbert-Kunz criterion for tight closure in positive characteristic.

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BibTeXRIS

Holger Brenner. 2004-03-17. A Hilbert-Kunz criterion for solid closure in dimension two (characteristic zero). https://arxiv.org/abs/math/0403285

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