{ "id": "1804.03049", "version": "v2", "published": "2018-04-09T15:06:23.000Z", "updated": "2018-09-14T16:16:14.000Z", "title": "Growth in linear algebraic groups and permutation groups: towards a unified perspective", "authors": [ "Harald A. Helfgott" ], "comment": "To appear in the proceedings of the St Andrews conference (2017). Minor corrections + grant information", "categories": [ "math.GR" ], "abstract": "By now, we have a product theorem in every finite simple group $G$ of Lie type, with the strength of the bound depending only in the rank of $G$. Such theorems have numerous consequences: bounds on the diameters of Cayley graphs, spectral gaps, and so forth. For the alternating group Alt_n, we have a quasipolylogarithmic diameter bound (Helfgott-Seress 2014), but it does not rest on a product theorem. We shall revisit the proof of the bound for Alt_n, bringing it closer to the proof for linear algebraic groups, and making some common themes clearer. As a result, we will show how to prove a product theorem for Alt_n -- not of full strength, as that would be impossible, but strong enough to imply the diameter bound.", "revisions": [ { "version": "v2", "updated": "2018-09-14T16:16:14.000Z" } ], "analyses": { "subjects": [ "20B05", "20B30", "30B35" ], "keywords": [ "linear algebraic groups", "permutation groups", "product theorem", "unified perspective", "quasipolylogarithmic diameter bound" ], "tags": [ "conference paper" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }