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arXiv · 1402.3431

A positivity conjecture for the Alvis-Curtis dual of the intersection cohomology of a Deligne-Lusztig variety

Olivier Dudas·Gunter Malle
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Abstract

We formulate a strong positivity conjecture on characters afforded by the Alvis-Curtis dual of the intersection cohomology of Deligne-Lusztig varieties. This conjecture provides a powerful tool to determine decomposition numbers of unipotent $\ell$-blocks of finite reductive groups.

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BibTeXRIS

Olivier Dudas, Gunter Malle. 2014-02-14. A positivity conjecture for the Alvis-Curtis dual of the intersection cohomology of a Deligne-Lusztig variety. https://arxiv.org/abs/1402.3431

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