{ "id": "1606.08872", "version": "v1", "published": "2016-06-28T20:21:19.000Z", "updated": "2016-06-28T20:21:19.000Z", "title": "Fourier Coefficients for Degenerate Eisenstein Series and the Descending Decomposition", "authors": [ "Yuanqing Cai" ], "categories": [ "math.RT", "math.CO", "math.NT" ], "abstract": "We determine the unipotent orbits attached to degenerate Eisenstein series on general linear groups. This confirms a conjecture of David Ginzburg. This also shows that any unipotent orbit of general linear groups does occur as the unipotent orbit attached to a specific automorphic representation. The key ingredient is a root-theoretic result. To prove it, we introduce the notion of the descending decomposition, which expresses every Weyl group element as a product of simple reflections in a certain way. It is suitable for induction and allows us to translate the question into a combinatorial statement.", "revisions": [ { "version": "v1", "updated": "2016-06-28T20:21:19.000Z" } ], "analyses": { "subjects": [ "11F30", "11F70", "05E10", "22E50", "22E55" ], "keywords": [ "degenerate eisenstein series", "descending decomposition", "fourier coefficients", "unipotent orbit", "general linear groups" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }