Canonical big Cohen-Macaulay algebras and rational singularities
نویسندگان
چکیده
منابع مشابه
Canonical Big Cohen-macaulay Algebras and Rational Singularities
We give a canonical construction of a balanced big Cohen-Macaulay algebra for a domain of finite type over C by taking ultraproducts of absolute integral closures in positive characteristic. This yields a new tight closure characterization of rational singularities in characteristic zero.
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ژورنال
عنوان ژورنال: Illinois Journal of Mathematics
سال: 2004
ISSN: 0019-2082
DOI: 10.1215/ijm/1258136178