Group theory
Projective modules in the intersection cohomology of Deligne–Lusztig varieties
[Modules projectifs dans la cohomologie d'intersection des variétiés de Deligne–Lusztig]
Comptes Rendus. Mathématique, Tome 352 (2014) no. 6, pp. 467-471.

Nous formulons une conjecture de positivité sur le dual d'Alvis–Curtis du caractère obtenu à partir de la cohomologie d'intersection d'une variété de Deligne–Lusztig. Cette conjecture se révèle être un outil puissant pour déterminer les nombres de décompositions des -blocs unipotents des groupes réductifs finis.

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 -blocks of finite reductive groups.

Reçu le :
Accepté le :
Publié le :
DOI : 10.1016/j.crma.2014.03.011
Dudas, Olivier 1 ; Malle, Gunter 2

1 Université Paris-Diderot, UFR de mathématiques, bâtiment Sophie-Germain, 5, rue Thomas-Mann, 75205 Paris cedex 13, France
2 FB Mathematik, TU Kaiserslautern, Postfach 3049, 67653 Kaiserslautern, Germany
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Dudas, Olivier; Malle, Gunter. Projective modules in the intersection cohomology of Deligne–Lusztig varieties. Comptes Rendus. Mathématique, Tome 352 (2014) no. 6, pp. 467-471. doi : 10.1016/j.crma.2014.03.011. http://www.numdam.org/articles/10.1016/j.crma.2014.03.011/

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