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arXiv · 1811.05824

Rigidity and unlikely intersections for formal groups

Laurent Berger
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Abstract

Let K be a p-adic field and let F and G be two formal groups over O_K. We prove that if F and G have infinitely many torsion points in common, then F=G. This follows from a rigidity result: any bounded power series that sends infinitely many torsion points of F to torsion points of F is an endomorphism of F.

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Laurent Berger. 2019-01-14. Rigidity and unlikely intersections for formal groups. https://arxiv.org/abs/1811.05824

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