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arXiv · 2403.11007

Central motives on parahoric flag varieties

Robert Cass·Thibaud van den Hove·Jakob Scholbach
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Abstract

We construct a refinement of Gaitsgory's central functor for integral motivic sheaves, and show it preserves stratified Tate motives. Towards this end, we develop a reformulation of unipotent motivic nearby cycles, which also works over higher-dimensional bases. We moreover introduce Wakimoto motives and use them to show that our motivic central functor is t-exact. A decategorification of these functors yields a new approach to generic Hecke algebras for general parahorics.

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Robert Cass, Thibaud van den Hove, Jakob Scholbach. 2024-03-16. Central motives on parahoric flag varieties. https://arxiv.org/abs/2403.11007

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