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arXiv · 2111.13056

Lattices with skew-Hermitian forms over division algebras and unlikely intersections

Abstract

This paper has two objectives. First, we study lattices with skew-Hermitian forms over division algebras with positive involutions. For division algebras of Albert types I and II, we show that such a lattice contains an "orthogonal" basis for a sublattice of effectively bounded index. Second, we apply this result to obtain new results in the field of unlikely intersections. More specifically, we prove the Zilber-Pink conjecture for the intersection of curves with special subvarieties of simple PEL type I and II under a large Galois orbits conjecture. We also prove this Galois orbits conjecture for certain cases of type II.

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BibTeXRIS

Christopher Daw, Martin Orr. 2023-05-15. Lattices with skew-Hermitian forms over division algebras and unlikely intersections. https://doi.org/10.5802/jep.240

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