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arXiv · 0909.4806

On the reduction of points on abelian varieties and tori

Antonella Perucca
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Abstract

Let G be the product of an abelian variety and a torus defined over a number field K. Let R_1,..., R_n be points in G(K). Let l be a rational prime and let a_1,..., a_n be non-negative integers. Consider the set of primes p of K satisfying the following condition: the l-adic valuation of the order of (R_i mod p) equals a_i for every i=1,...,n. We show that this set has a natural density and we characterize the n-tuples a_1,..., a_n for which the density is positive. More generally, we study the l-part of the reduction of the points.

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Antonella Perucca. 2009-09-25. On the reduction of points on abelian varieties and tori. https://arxiv.org/abs/0909.4806

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