Connected components of closed affine Deligne-Lusztig varieties in affine Grassmannians
نویسندگان
چکیده
منابع مشابه
Connected Components of Closed Affine Deligne-lusztig Varieties
We determine the set of connected components of closed affine Deligne-Lusztig varieties for special maximal compact subgroups of split connected reductive groups. We show that there is a transitive group action on this set. Thus such an affine Deligne-Lusztig variety has isolated points if and only if its dimension is 0. We also obtain a description of the set of these varieties that are zero-d...
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Let k be a finite field with q elements, and let k̄ be an algebraic closure of k. We consider the field L := k̄((ǫ)) and its subfield F := k((ǫ)). We write σ : x 7→ x for the Frobenius automorphism of k̄/k, and we also regard σ as an automorphism of L/F in the usual way, so that σ( ∑ anǫ ) = ∑ σ(an)ǫ . We write o for the valuation ring k̄[[ǫ]] of L. Let G be a split connected reductive group over k...
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ژورنال
عنوان ژورنال: American Journal of Mathematics
سال: 2018
ISSN: 1080-6377
DOI: 10.1353/ajm.2018.0034