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arXiv · 2307.10516

On the geography of $3$-folds via asymptotic behavior of invariants

Yerko Torres-Nova
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Abstract

Roughly speaking, the problem of geography asks for the existence of varieties of general type after we fix some invariants. In dimension $1$, where we fix the genus, the geography question is trivial, but already in dimension $2$, it becomes a hard problem in general. In higher dimensions, this problem is essentially wide open. In this paper, we focus on geography in dimension $3$. We generalize the techniques which compare the geography of surfaces with the geography of arrangements of curves via asymptotic constructions. In dimension $2$ this involves resolutions of cyclic quotient singularities and a certain asymptotic behavior of the associated Dedekind sums and continued fractions. We discuss the general situation with emphasis on dimension $3$, analyzing the singularities and various resolutions that show up, and proving results about the asymptotic behavior of the invariants we fix.

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Yerko Torres-Nova. 2023-07-20. On the geography of $3$-folds via asymptotic behavior of invariants. https://arxiv.org/abs/2307.10516

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