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arXiv · 2609.39079

Singularities of orbit closures in loop spaces of symmetric varieties II: twisted cases

Tsao-Hsien Chen·Lingfei Yi
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Abstract

We study the singularities of orbit closures in loop symmetric varieties, extending our previous work https://arxiv.org/abs/2310.20006 to the twisted setting. We prove that the IC complexes of orbit closures are pointwise pure and satisfy a parity-vanishing property. We apply these geometric results to the study of twisted affine Lusztig--Vogan modules, establishing foundational results, including positivity properties of the twisted affine Kazhdan--Lusztig--Vogan polynomials. Along the way, we construct conical symplectic transversal slices in loop symmetric spaces. We provide applications to Langlands duality for real groups.

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Tsao-Hsien Chen, Lingfei Yi. 2026-09-30. Singularities of orbit closures in loop spaces of symmetric varieties II: twisted cases. https://arxiv.org/abs/2609.39079

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