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arXiv · 2409.14933

Adjoint $L$-functions, congruence ideals, and Selmer groups over $\mathrm{GL}_n$

Ho Leung Fong
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Abstract

In this paper, we relate $L(1,\pi,\mathrm{Ad}^\circ)$ to the congruence ideals for cohomological cuspidal automorphic representations $\pi$ of $\mathrm{GL}_n$ over any number field. We then use this result to deduce relationships between the congruences of automorphic forms and adjoint $L$-functions. For CM and totally real fields, we apply the result to obtain a lower bound on the cardinality of certain Selmer groups in terms of $L(1,\pi,\mathrm{Ad}^\circ)$.

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Ho Leung Fong. 2024-09-23. Adjoint $L$-functions, congruence ideals, and Selmer groups over $\mathrm{GL}_n$. https://arxiv.org/abs/2409.14933

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