On the existence of birational maximal Cohen-Macaulay modules over biradical extensions in mixed characteristic
نویسندگان
چکیده
Let S be an unramified regular local ring of mixed characteristic p≥3 and Sp the subring obtained by lifting to image Frobenius map on S/pS. R integral closure in a biradical extension degree p2 its quotient field adjoining p-th roots sufficiently general square free elements f,g∈Sp. We show that admits birational maximal Cohen-Macaulay module. It is noted not automatically Cohen-Macaulay.
منابع مشابه
ON THE EXISTENCE OF MAXIMAL COHEN-MACAULAY MODULES OVER p th ROOT EXTENSIONS
Let S be an unramified regular local ring having mixed characteristic p > 0 and R the integral closure of S in a pth root extension of its quotient field. We show that R admits a finite, birational module M such that depth(M) = dim(R). In other words, R admits a maximal Cohen-Macaulay module.
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ژورنال
عنوان ژورنال: Journal of Pure and Applied Algebra
سال: 2021
ISSN: ['1873-1376', '0022-4049']
DOI: https://doi.org/10.1016/j.jpaa.2021.106790