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Coefficient fields and scalar extension in positive characteristic

M. Fernandez-Lebron·L. Narvaez-Macarro
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Abstract

Let k be a perfect field of positive characteristic, k(t)_{per} the perfect closure of k(t) and A=k[[X_1,...,X_n]]. We show that for any maximal ideal N of A'=k(t)_{per}\otimes_k A, the elements in \hat{A'_N} which are annihilated by the "Taylor" Hasse-Schmidt derivations with respect to the X_i form a coefficient field of \hat{A'_N}.

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BibTeXRIS

M. Fernandez-Lebron, L. Narvaez-Macarro. 2005-05-19. Coefficient fields and scalar extension in positive characteristic. https://doi.org/10.1016/j.jalgebra.2004.11.009

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