On the connectedness of Deligne-Lusztig varieties

Görtz, Ulrich

doi:10.1090/S1088-4165-09-00344-6

On the connectedness of Deligne-Lusztig varieties

Author: Ulrich Görtz
Journal: Represent. Theory 13 (2009), 1-7
MSC (2000): Primary 14L35; Secondary 20G40
DOI: https://doi.org/10.1090/S1088-4165-09-00344-6
Published electronically: January 21, 2009
MathSciNet review: 2471197
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Abstract: We give a criterion which determines when a union of one-dimensional Deligne-Lusztig varieties has a connected closure. We obtain a new, short proof of the connectedness criterion for Deligne-Lusztig varieties due to Lusztig.

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