{ "id": "2301.09812", "version": "v1", "published": "2023-01-24T04:41:41.000Z", "updated": "2023-01-24T04:41:41.000Z", "title": "Characterization of supercuspidal representations and very regular elements", "authors": [ "Charlotte Chan", "Masao Oi" ], "comment": "75 pages", "categories": [ "math.RT", "math.NT" ], "abstract": "We prove that regular supercuspidal representations of $p$-adic groups are uniquely determined by their character values on very regular elements -- a special class of regular semisimple elements on which character formulae are very simple -- provided that this locus is sufficiently large. As a consequence, we resolve a question of Kaletha by giving a description of Kaletha's $L$-packets of regular supercuspidal representations which mirrors Langlands' construction for real groups following Harish-Chandra's characterization theorem for discrete series representations. Our techniques additionally characterize supercuspidal representations in general, giving $p$-adic analogues of results of Lusztig on reductive groups over finite fields. In particular, we establish an easy, non-cohomological characterization of unipotent supercuspidal representations when the residue field of the base field is sufficiently large.", "revisions": [ { "version": "v1", "updated": "2023-01-24T04:41:41.000Z" } ], "analyses": { "subjects": [ "22E50", "11S37", "11F70" ], "keywords": [ "regular elements", "regular supercuspidal representations", "sufficiently large", "harish-chandras characterization theorem", "techniques additionally characterize supercuspidal representations" ], "note": { "typesetting": "TeX", "pages": 75, "language": "en", "license": "arXiv", "status": "editable" } } }