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Connected components of closed affine Deligne-Lusztig varieties

Eva Viehmann
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Abstract

We determine the set of connected components of closed affine Deligne-Lusztig varieties for special maximal compact subgroups of split connected reductive groups. Especially, we show that such an affine Deligne-Lusztig variety has isolated points if and only if its dimension is 0. From the dimension formula for affine Deligne-Lusztig varieties we obtain a description of the set of these varieties that are zero-dimensional.

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Eva Viehmann. 2007-07-30. Connected components of closed affine Deligne-Lusztig varieties. https://arxiv.org/abs/math/0607678

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