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arXiv · 1601.06170

Further counterexamples to the integral Hodge conjecture

Arnav Tripathy
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Abstract

We study the integral Hodge conjecture in complex codimension $2$ and $3$ for approximations to the classifying space of groups of type A. In degree two, we prove a conjecture of Ben Antieau, extending his two counterexamples to a general family of groups. In particular, when reduced to a finite field, these spaces extend Antieau's counterexamples to the integral $\ell$-adic Tate conjecture from the cases $\ell = 2, 3$ to all primes $\ell$.

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Arnav Tripathy. 2016-01-22. Further counterexamples to the integral Hodge conjecture. https://arxiv.org/abs/1601.06170

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