Unipotent representations as a categorical centre

G. Lusztig

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arXiv · 1401.2889

Unipotent representations as a categorical centre

G. Lusztig

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Abstract

Let G(F_q) be the group of rational points of a split connected reductive group G defined over the finite field F_q. In this paper we show that the category of representations of G(F_q) which are finite direct sums of unipotent representations in a fixed two-sided cell is equivalent to the centre of a certain monoidal category of sheaves on the product of two copies of the flag manifold of G. We also consider a version of this for nonsplit groups.

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BibTeX RIS

G. Lusztig. 2014-01-13. Unipotent representations as a categorical centre. https://arxiv.org/abs/1401.2889

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