Separable integral extensions and plus closure

2002/10/07 by Anurag K. Singh
Mathematics · #math.AC #msc:13C14 #msc:13A35 #msc:13H10

paper · pdf

published as Manuscripta Mathematica 98 (1999) 497-506

arxiv created 2002/10/07 · arxiv updated 2009/11/30

Abstract

Let R be an excellent local domain of positive characteristic, and R⁺ denote the integral closure of R in an algebraic closure of its fraction field. Hochster and Huneke proved that R⁺ is a big Cohen-Macaulay algebra for R, and asked if there is a smaller R-algebra with the Cohen-Macaulay property. In this paper we establish the existence of a smaller big Cohen-Macaulay algebra which is, moreover, a separable extension.

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