Pure subrings of regular rings are pseudo-rational

Schoutens, Hans

doi:10.1090/S0002-9947-07-04134-7

Pure subrings of regular rings are pseudo-rational
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Trans. Amer. Math. Soc. 360 (2008), 609-627 Request permission

Abstract:

We prove a generalization conjectured by Aschenbrenner and Schoutens (2003) of the Hochster-Roberts-Boutot-Kawamata Theorem: let $R\to S$ be a pure homomorphism of equicharacteristic zero Noetherian local rings. If $S$ is regular, then $R$ is pseudo-rational, and if $R$ is moreover $\mathbb Q$-Gorenstein, then it is pseudo-log-terminal.

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