A torsion property of the zero of Kodaira-Spencer over $\mathbb{P}^1$ removing four points

Xiaojin Lin; Mao Sheng; Jianping Wang

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arXiv · 2212.02038

A torsion property of the zero of Kodaira-Spencer over $\mathbb{P}^1$ removing four points

Xiaojin Lin·Mao Sheng·Jianping Wang

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Abstract

We establish a torsion theorem to the effect that the unique zero of the Kodaira-Spencer map attached to a certain quasi-semistable family of complex projective varieties over the complex projective line is the image of a torsion point of an elliptic curve under the natural projection. The proof is a mod $p$ argument and requires a density one set of primes. There are three essential ingredients in the proof: a solution to the conjecture of Sun-Yang-Zuo, which constitutes the principal part of the paper, Pink's theorem, and Higgs periodicity theorem.

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Xiaojin Lin, Mao Sheng, Jianping Wang. 2023-05-10. A torsion property of the zero of Kodaira-Spencer over $\mathbb{P}^1$ removing four points. https://arxiv.org/abs/2212.02038

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