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arXiv · 2210.15166

Residual spectrum of $\mathrm{GL}_{2n}$ distinguished by $\mathrm{GL}_n \times \mathrm{GL}_n$

Chang Yang
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Abstract

Following the regularization method presented by Zydor, we study in this paper the regularized linear periods of square-integrable automormphic forms on $\mathrm{GL}_{2n}(\mathbb{A}_F)$, where $F$ is a number field and $\mathbb{A}_F$ its ring of adeles. We obtain a formula that expresses the regularized period of a noncuspidal, square-integrable automorphic form in terms of degenerate Whittaker functions in an inductive manner. As a consequence we characterize irreducible automorphic representations in the discrete spectrum of $\mathrm{GL}_{2n}(\mathbb{A})$ that are distinguished by $\mathrm{GL}_n(\mathbb{A}) \times \mathrm{GL}_n(\mathbb{A})$. We also show the vanishing of the regularized periods of square-integrable automorphic forms on $\mathrm{GL}_n(\mathbb{A})$ over $\mathrm{GL}_p(\mathbb{A}) \times \mathrm{GL}_q(\mathbb{A})$ when $p$ is not equal to $q$.

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BibTeXRIS

Chang Yang. 2022-10-27. Residual spectrum of $\mathrm{GL}_{2n}$ distinguished by $\mathrm{GL}_n \times \mathrm{GL}_n$. https://arxiv.org/abs/2210.15166

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