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arXiv · 1610.01264

Koszul Factorization and the Cohen-Gabber Theorem

Chris Skalit
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Abstract

We present a sharpened version of the Cohen-Gabber theorem for equicharacteristic, complete local domains (A,m,k) with algebraically closed residue field and dimension d > 0. Namely, we show that for any prime number p, Spec(A) admits a dominant, finite map to Spec(k[[X_1,...,X_d]]) with generic degree relatively prime to p. Our result follows from Gabber's original theorem, elementary Hilbert-Samuel multiplicity theory, and a "factorization" of the map induced on the Grothendieck group G_0(A) by the Koszul complex.

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Chris Skalit. 2016-10-05. Koszul Factorization and the Cohen-Gabber Theorem. https://arxiv.org/abs/1610.01264

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