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arXiv · 2603.19998

The log homotopy exact sequence

Mattia Talpo
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Abstract

We show exactness of the homotopy sequence for the logarithmic fundamental group in the case of log smooth, finitely presented, proper and saturated morphisms of fs log schemes over a field. This generalizes earlier results of Hoshi in the log regular case. In passing, we also construct a "log Stein factorization" in some particular cases.

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Mattia Talpo. 2026-03-20. The log homotopy exact sequence. https://arxiv.org/abs/2603.19998

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