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arXiv · 2610.09269

Fundamental groups of Calabi-Yau spaces

Xin Fu·Bin Guo·Jian Song·Juanyong Wang
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Abstract

We study the fundamental groups of a normal projective Calabi-Yau variety $X$ with klt singularities and of its regular locus $X_{reg}$. We prove that both groups are almost abelian, and that their ranks are determined by the irregularities of finite etale and quasi-etale covers, respectively. Our approach is differential geometric, and relies on recent advances in the geometric theory of complex Monge-Ampere equations.

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Xin Fu, Bin Guo, Jian Song, Juanyong Wang. 2026-10-07. Fundamental groups of Calabi-Yau spaces. https://arxiv.org/abs/2610.09269

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