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arXiv · 2008.04728

Frobenius-Witt differentials and regularity

Takeshi Saito
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Abstract

T. Dupuy, E. Katz, J. Rabinoff, D. Zureick-Brown introduced the module of total $p$-differentials for a ring over $Z/p^2Z$. We study the same construction for a ring over $Z_{(p)}$ and prove a regularity criterion. For a local ring, the tensor product with the residue field is constructed in a different way by O. Gabber, L. Ramero. In another article arXiv:2006.00448, we use the sheaf of FW-differentials to define the cotangent bundle and the micro-support of an etale sheaf.

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Takeshi Saito. 2020-08-10. Frobenius-Witt differentials and regularity. https://doi.org/10.2140/ant.2022.16.369

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