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arXiv · 2305.00683

Newton Strata in Levi Subgroups

Felix Schremmer
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Abstract

Certain Iwahori double cosets in the loop group of a reductive group, known under the names of $P$-alcoves or $(J,w,\delta)$-alcoves, play an important role in the study of affine Deligne-Lusztig varieties. For such an Iwahori double coset, its Newton stratification is related to the Newton stratification of an Iwahori double coset in a Levi subgroup. We show that this relation is closer than previously known.

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Felix Schremmer. 2023-05-01. Newton Strata in Levi Subgroups. https://doi.org/10.1007/s00229-024-01566-y

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