On the Connectedness of Deligne-lusztig Varieties
نویسنده
چکیده
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.
منابع مشابه
Affine Deligne–lusztig Varieties at Infinite Level (preliminary Version)
Part 1. Two analogues of Deligne–Lusztig varieties for p-adic groups 5 2. Affine Deligne–Lusztig varieties at infinite level 5 2.1. Preliminaries 5 2.2. Deligne–Lusztig sets/varieties 7 2.3. Affine Deligne–Lusztig varieties and covers 8 2.4. Scheme structure 9 3. Case G = GLn, b basic, w Coxeter 12 3.1. Notation 12 3.2. Basic σ-conjucacy classes. Isocrystals 12 3.3. The admissible subset of Vb ...
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