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arXiv · 2201.08063

Hypergeometric sheaves for classical groups via geometric Langlands

Abstract

In a previous paper, the first and third authors gave an explicit realization of the geometric Langlands correspondence for hypergeometric sheaves, considered as $\textrm{GL}_n$-local systems. Certain hypergeometric local systems admit a symplectic or orthogonal structure, which can be viewed as $\check{G}$-local systems, for a classical group $\check{G}$. This article aims to realize the geometric Langlands correspondence for these $\check{G}$-local systems. We study this problem from two aspects. In the first approach, we define the hypergeometric automorphic data for a classical group $G$ in the framework of Yun, one of whose local components is a new class of euphotic representations in the sense of Jakob-Yun. We prove the rigidity of hypergeometric automorphic data under natural assumptions, which allows us to define $\check{G}$-local systems $\mathcal{E}_{\check{G}}$ on $\mathbb{G}_m$ as Hecke eigenvalues (in both $\ell$-adic and de Rham setting). In the second approach (which works only in the de Rham setting), we quantize an enhanced ramified Hitchin system, following Beilinson-Drinfeld and Zhu, and identify $\mathcal{E}_{\check{G}}$ with certain $\check{G}$-opers on $\mathbb{G}_m$. Finally, we compare these $\check{G}$-opers with hypergeometric local systems.

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BibTeXRIS

Masoud Kamgarpour, Daxin Xu, Lingfei Yi. 2022-01-20. Hypergeometric sheaves for classical groups via geometric Langlands. https://arxiv.org/abs/2201.08063

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