An excellent $F$-pure ring of prime characteristic has a big tight closure test element
نویسندگان
چکیده
منابع مشابه
The Root Closure of a Ring of Mixed Characteristic
We define a closure operation for rings of mixed characteristic and verify that the closure is a ring. We then show that this closure produces a ring with good properties with respect to its Fontaine ring and give an example to show that rings that are not closed in this sense do not satisfy these properties.
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 2010
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-10-05166-4