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arXiv · 2003.07827

Extensions in the cohomology of Hilbert modular varieties

Cosmin Davidescu·Anthony J. Scholl
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Abstract

We describe extension classes arising in the $\ell$-adic and Hodge cohomology of Hilbert modular varieties, generalising results of Caspar to arbitrary dimensions. We show that this description is consistent with the "plectic conjectures" of Nekovář and the second author.

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Cosmin Davidescu, Anthony J. Scholl. 2020-03-17. Extensions in the cohomology of Hilbert modular varieties. https://arxiv.org/abs/2003.07827

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