{ "id": "2210.16291", "version": "v1", "published": "2022-10-28T17:37:24.000Z", "updated": "2022-10-28T17:37:24.000Z", "title": "On the local $L^2$-Bound of the Eisenstein Series", "authors": [ "Subhajit Jana", "Amitay Kamber" ], "comment": "47 pages", "categories": [ "math.NT", "math.RT" ], "abstract": "We study the growth of the local $L^2$-norms of the unitary Eisenstein series for reductive groups over number fields, in terms of their parameters. In this work, we show an upper bound of the squared $L^2$-norms of the unitary Eisenstein series restricted to a fixed compact domain, of \\emph{poly-logarithmic} strength on an average, for a large class of reductive groups. Moreover, as an application of our method, we prove the optimal lifting property for $\\mathrm{SL}_n(\\mathbb{Z}/q\\mathbb{Z})$ for square-free $q$, as well as the Sarnak--Xue counting property for the principal congruence subgroup of $\\mathrm{SL}_n(\\mathbb{Z})$ of square-free level. This makes the recent results of Assing--Blomer unconditional.", "revisions": [ { "version": "v1", "updated": "2022-10-28T17:37:24.000Z" } ], "analyses": { "subjects": [ "11F70", "11F72", "22E55" ], "keywords": [ "unitary eisenstein series", "reductive groups", "principal congruence subgroup", "number fields", "upper bound" ], "note": { "typesetting": "TeX", "pages": 47, "language": "en", "license": "arXiv", "status": "editable" } } }