2025/12/18 by Pierre-Henri Chaudouard, Chaudouard, Pierre-Henri
Mathematics · #Advanced Algebra and Geometry #Analytic Number Theory Research #Algebraic Geometry and Number Theory
paper · doi:10.48550/arxiv.2512.17056
Let p≥ 1. The symmetric space S=GL(2p+1)/GL(p+1)× GL(p) (over a number field) is not cuspidal in the sense that its automorphic spectrum does not contain any cuspidal representation of GL(2p+1). In this article, we compute the spectral decomposition of its relatively cuspidal part: this is, by definition, the part of the spectrum that is induced from the cuspidal part of the symmetric space (GL(1)× GL(2p)) / (GL(1)× GL(p)× GL(p)). As an application, we obtain the expression of the contribution of this relatively cuspidal part to the Guo-Jacquet trace formula (established by H. Li and the author) in terms of a weighted relative character.