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arXiv · 2412.12078

The many faces of a logarithmic scheme

Thibault Poiret·Dhruv Ranganathan
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Abstract

A standard assumption in the study of logarithmic structures is "fineness", but this assumption is not preserved by intersections, fiber products, and more general limits. We explain how a coherent logarithmic scheme $X$ has a natural decomposition into "fine faces" -- a collection of fine logarithmic subschemes. This allows for importation of the techniques of tropical geometry into the study of more general logarithmic schemes. We explain the relevance of the construction in enumerative geometry and moduli via a range of examples. Techniques developed in the study of binomial schemes lead to effective algorithms for computing the fine faces.

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Thibault Poiret, Dhruv Ranganathan. 2024-12-16. The many faces of a logarithmic scheme. https://arxiv.org/abs/2412.12078

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