L-indistinguishability for covering groups of algebraic tori

Yuki Nakata

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arXiv · 2605.14307

L-indistinguishability for covering groups of algebraic tori

Yuki Nakata

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Abstract

A global packet may simultaneously contain an automorphic representation and a non-automorphic representation. The global $\mathcal S$-group is expected, and known in some cases, to specify the automorphic representations in each global packet. For a covering group of an algebraic torus, it is not obvious from the definition whether the analogue of a global $\mathcal S$-group has finite order. In this paper, we verify this finiteness for a Brylinski-Deligne covering group of a torus.

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Yuki Nakata. 2026-05-14. L-indistinguishability for covering groups of algebraic tori. https://arxiv.org/abs/2605.14307

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