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arXiv · 1510.08836

The Galois action on geometric lattices and the mod-$\ell$ I/OM

Adam Topaz
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Abstract

This paper studies the Galois action on a special lattice of geometric origin, which is related to mod-$\ell$ abelian-by-central quotients of geometric fundamental groups of varieties. As a consequence, we formulate and prove the mod-$\ell$ abelian-by-central variant/strengthening of a conjecture due to Ihara/Oda-Matsumoto.

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Adam Topaz. 2015-10-29. The Galois action on geometric lattices and the mod-$\ell$ I/OM. https://arxiv.org/abs/1510.08836

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