Aubert duals of strongly positive representations for metaplectic groups

Yeansu Kim; Gyujin Oh

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arXiv · 2512.23218

Aubert duals of strongly positive representations for metaplectic groups

Yeansu Kim·Gyujin Oh

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Abstract

We determine the Aubert duals of strongly positive representations of the metaplectic group $\widetilde{Sp}(n)$ over a non-Archimedean local field $F$ of characteristic different from two. Using the classification of Mati\'c and an explicit analysis of Jacquet modules, we describe these duals in terms of precise inducing data. Our results extend known descriptions for classical groups to the metaplectic groups case and clarify the role of Aubert duality for non-linear covering groups, providing a foundation for future applications to the study of unitary representations for those cases. Furthermore, We are able to show that the same method applies to odd general spin groups $GSpin(2n+1)$, yielding an explicit description of Aubert duals in that setting as well.

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Yeansu Kim, Gyujin Oh. 2025-12-29. Aubert duals of strongly positive representations for metaplectic groups. https://arxiv.org/abs/2512.23218

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