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arXiv · 1708.01351

Local heuristics and an exact formula for abelian varieties of odd prime dimension over finite fields

Jonathan Gerhard·Cassie Williams
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Abstract

Consider a $q$-Weil polynomial $f$ of degree $2g$. Using an equidistribution assumption that is too strong to be true, we define and compute a product of local relative densities of matrices in $\rm{GSp}_{2g}(\mathbb{F}_\ell)$ with characteristic polynomial $f\mod\ell$ when $g$ is an odd prime. This infinite product is closely related to a ratio of class numbers. When $g=3$ we conjecture that the product gives the size of an isogeny class of principally polarized abelian threefolds.

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Jonathan Gerhard, Cassie Williams. 2017-08-04. Local heuristics and an exact formula for abelian varieties of odd prime dimension over finite fields. https://arxiv.org/abs/1708.01351

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