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arXiv · 2205.06288

Poles of degenerate Eisenstein series and Siegel-Weil identities for exceptional split groups

Hezi Halawi
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Abstract

Let $G$ be a linear split algebraic group. The degenerate Eisenstein series associated to a maximal parabolic subgroup $E_{P}(f^{0},s,g)$ with the spherical section $f^{0}$ is studied in the first part of the thesis. In this part, we study the poles of $E_{P}(f^{0},s,g)$ in the region $\operatorname{Re} s >0$. We determine when the leading term in the Laurent expansion of $E_{P}(f^{0},s,g)$ around $s=s_0$ is square integrable. The second part is devoted to finding identities between the leading terms of various Eisenstein series at different points. We present an algorithm to find this data and implement it on \textit{SAGE}. While both parts can be applied to a general algebraic group, we restrict ourself to the case where $G$ is split exceptional group of type $F_4,E_6,E_7$, and obtain new results.

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Hezi Halawi. 2022-05-12. Poles of degenerate Eisenstein series and Siegel-Weil identities for exceptional split groups. https://arxiv.org/abs/2205.06288

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