English

Hybrid Conjecture in a Mixed Shimura variety

Number Theory 2026-04-28 v1 Algebraic Geometry

Abstract

The authors previously formulated the hybrid conjecture, unifying Andr\'e-Pink-Zannier and Andr\'e-Oort conjectures, and proved it in Shimura varieties of abelian type. We study its analogue for mixed Shimura varieties, and consider the prime example, the universal abelian scheme AgAg\mathcal{A}_g\to \mathbb{A}_g. In a radical departure from the Pila-Zannier strategy, typically applied to such questions, we employ instead a combination of equidistribution and o-minimality Our main result strictly includes the following: the Hybrid Conjecture, in particular the Andr\'e-Pink-Zannier and Andr\'e-Oort conjectures, for Ag\mathbb{A}_g; the mixed Andr\'e-Oort conjecture for Ag\mathcal{A}_g; and Manin-Mumford conjecture for arbitrary abelian varieties. It also yields an analogue of the ``Manin-Mumford in arithmetic pencil", a result of Baldi-Richard-Ullmo, for abelian schemes over a variety. The mixed hybrid conjecture in Ag\mathcal{A}_g also encompasses the Mordell-Lang conjecture. We actually reduce the mixed hybrid conjecture for Ag\mathbb{A}_g to its "mordellic" part. We also prove, Galois-theoretic results: uniform variants on the Ribet's Kummer theory of Abelian varieties, and Serre's theorem on Lang's conjecture.

Keywords

Cite

@article{arxiv.2604.23376,
  title  = {Hybrid Conjecture in a Mixed Shimura variety},
  author = {Rodolphe Richard and Andrei Yafaev},
  journal= {arXiv preprint arXiv:2604.23376},
  year   = {2026}
}
R2 v1 2026-07-01T12:35:14.163Z