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arXiv · 2409.03442

A criterion for $p$-closedness of derivations in dimension two

Kentaro Mitsui·Nobuo Sato
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Abstract

Jacobson developed a counterpart of Galois theory for purely inseparable field extensions in positive characteristic. In his theory, a certain type of derivations replace the role of the generators of Galois groups. This article provides a convenient criterion for determining such derivations in dimension two. We also present examples demonstrating the efficiency of our criterion.

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Kentaro Mitsui, Nobuo Sato. 2024-09-05. A criterion for $p$-closedness of derivations in dimension two. https://arxiv.org/abs/2409.03442

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