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arXiv · 2607.20296

Effective characterization of semi-abelian varieties

Jefferson Baudin·Sofia Tirabassi
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Abstract

We obtain effective characterizations of complex semi-abelian varieties in arbitrary dimension in terms of logarithmic irregularity and the first two logarithmic plurigenera, among varieties of maximal Albanese dimension, and among varieties whose compactification has large irregularity (these hypotheses are sharp). To the authors' knowledge, this is the first result in this direction for quasi-projective varieties in arbitrary dimension.

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Jefferson Baudin, Sofia Tirabassi. 2026-07-22. Effective characterization of semi-abelian varieties. https://arxiv.org/abs/2607.20296

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