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arXiv · 1903.02038

Minimal Newton strata in Iwahori double cosets

Eva Viehmann
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Abstract

The set of Newton strata in a given Iwahori double coset in the loop group of a reductive group G is indexed by a finite subset of the set B(G) of Frobenius-conjugacy classes. For unramified $G$ we show that it has a unique minimal element and determine this element. Under a regularity assumption we also compute the dimension of the corresponding Newton stratum. We derive corresponding results for affine Deligne-Lusztig varieties.

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Eva Viehmann. 2019-03-05. Minimal Newton strata in Iwahori double cosets. https://arxiv.org/abs/1903.02038

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