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arXiv · 2604.17394

A criterion for log regularity via log Frobenius-Witt differentials

Ryoma Takeuchi
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Abstract

T. Saito introduced FW-derivations and the modules of FW-differentials. He gave a regularity criterion in terms of the modules of FW-differentials. In this paper, we introduce logarithmic analogues of FW-derivations and the modules of FW-differentials. We study basic properties of them and give a logarithmic regularity criterion in terms of the modules of logarithmic FW-differentials.

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Ryoma Takeuchi. 2026-04-19. A criterion for log regularity via log Frobenius-Witt differentials. https://arxiv.org/abs/2604.17394

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