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arXiv · 1507.04766

Lattices in the cohomology of $U(3)$ arithmetic manifolds

Daniel Le
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Abstract

Under hypotheses required for the Taylor-Wiles method, we prove for forms of $U(3)$ which are compact at infinity that the lattice structure on upper alcove algebraic vectors or on principal series types given by the $\lambda$-isotypic part of completed cohomology is a local invariant of the Galois representation attached to $\lambda$ when this Galois representation is residually irreducible locally at places dividing $p$. As a crucial input, we establish corresponding mod $p$ multiplicity one results. Our main innovation is the combination of integral Hecke theory and the Taylor--Wiles method.

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Daniel Le. 2015-07-16. Lattices in the cohomology of $U(3)$ arithmetic manifolds. https://arxiv.org/abs/1507.04766

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