On the Torsion Subgroup of the Néron--Severi Group

Kaiyuan Gu

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arXiv · 2610.34115

On the Torsion Subgroup of the Néron--Severi Group

Kaiyuan Gu

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Abstract

We prove an explicit bound for the torsion subgroup of the Néron--Severi group of a smooth projective complex variety. The proof combines the Diophantine-approximation method of Ziyang Gao and the author (https://arxiv.org/abs/2608.22285) with Lefschetz fibrations. As an application, we deduce an explicit bound for the torsion sections of a traceless abelian scheme over a complex curve.

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Kaiyuan Gu. 2026-10-25. On the Torsion Subgroup of the Néron--Severi Group. https://arxiv.org/abs/2610.34115

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