On the Torsion Subgroup of the Néron--Severi Group

Source 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.