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arXiv · 2506.19390

Perversity of coinvariants of affine Springer sheaves

Alexis Bouthier·David Kazhdan·Yakov Varshavsky
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Abstract

Using techniques of [BKV], we construct a perverse t-structure on the infinity-category of l-adic LG-equivariant sheaves on the regular-semisimple bounded locus of the loop group LG and prove that the derived $\tau$-coinvariants of affine Grothendieck--Springer sheaves are perverse. Our main new ingredient is a theorem of Yun on compatibility of actions.

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Alexis Bouthier, David Kazhdan, Yakov Varshavsky. 2025-06-24. Perversity of coinvariants of affine Springer sheaves. https://arxiv.org/abs/2506.19390

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