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arXiv · 1109.3522

Maximal varieties and the local Langlands correspondence for GL(n)

Mitya Boyarchenko·Jared Weinstein
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Abstract

The cohomology of the Lubin-Tate tower is known to realize the local Langlands correspondence for GL(n) over a nonarchimedean local field. In this article we make progress towards a purely local proof of this fact. To wit, we find a family of open affinoid subsets of Lubin-Tate space at infinite level, whose cohomology realizes the local Langlands correspondence for a broad class of supercuspidals (those whose Weil parameters are induced from an unramified degree n extension). A key role is played by a certain variety X, defined over a finite field, which is "maximal" in the sense that the number of rational points of X is the largest possible among varieties with the same Betti numbers as X. The variety X is derived from a certain unipotent algebraic group, in an analogous manner as Deligne-Lusztig varieties are derived from reductive algebraic groups.

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Mitya Boyarchenko, Jared Weinstein. 2011-09-16. Maximal varieties and the local Langlands correspondence for GL(n). https://arxiv.org/abs/1109.3522

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