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arXiv · 2210.14001

The Hilbert symbol in the Hodge standard conjecture

Giuseppe Ancona·Adriano Marmora
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Abstract

We study the Hodge standard conjecture for varieties over finite fields admitting a CM lifting, such as abelian varieties or products of K3 surfaces. For those varieties we show that the signature predicted by the conjecture holds true modulo $4$. This amounts to determining the discriminant and the Hilbert symbol of the intersection product. The first is obtained by $\ell$-adic arguments whereas the second needs a careful computation in $p$-adic Hodge theory.

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Giuseppe Ancona, Adriano Marmora. 2022-10-25. The Hilbert symbol in the Hodge standard conjecture. https://arxiv.org/abs/2210.14001

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