\'Etale metaplectic covers of reductive group schemes

Yifei Zhao

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arXiv · 2204.00610

\'Etale metaplectic covers of reductive group schemes

Yifei Zhao

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Abstract

Given a reductive group scheme $G$, we give a linear algebraic description of reduced \'etale $4$-cocycles on its classifying stack $\mathrm B(G)$. These cocycles form a $2$-groupoid, which we interpret as parameters of metaplectic covers of $G$. We use our linear algebraic description to define the Langlands dual of a metaplectic cover.

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Yifei Zhao. 2022-04-01. \'Etale metaplectic covers of reductive group schemes. https://arxiv.org/abs/2204.00610

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