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arXiv · 2304.01135

Regular logarithmic connections

Piotr Achinger
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Abstract

We introduce the notion of a regular integrable connection on a smooth log scheme over $\mathbf{C}$ and construct an equivalence between the category of such connections and the category of integrable connections on its analytification, compatible with de Rham cohomology. This extends the work of Deligne (when the log structure is trivial), and combined with the work of Ogus yields a topological description of the category of regular connections in terms of certain constructible sheaves on the Kato--Nakayama space. The key ingredients are the notion of a canonical extension in this context and the existence of good compactifications of log schemes obtained recently by W{\l}odarczyk.

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Piotr Achinger. 2023-04-03. Regular logarithmic connections. https://arxiv.org/abs/2304.01135

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