{ "id": "2002.05468", "version": "v1", "published": "2020-02-13T12:16:05.000Z", "updated": "2020-02-13T12:16:05.000Z", "title": "Braid groups of normalizers of reflection subgroups", "authors": [ "Thomas Gobet", "Anthony Henderson", "Ivan Marin" ], "comment": "22 pages", "categories": [ "math.RT", "math.GR" ], "abstract": "Let $W_0$ be a reflection subgroup of a finite complex reflection group $W$, and let $B_0$ and $B$ be their respective braid groups. In order to construct a Hecke algebra $\\widetilde{H}_0$ for the normalizer $N_W(W_0)$, one first considers a natural subquotient $\\widetilde{B}_0$ of $B$ which is an extension of $N_W(W_0)/W_0$ by $B_0$. We prove that this extension is split when $W$ is a Coxeter group, and deduce a standard basis for the Hecke algebra $\\widetilde{H}_0$. We also give classes of both split and non-split examples in the non-Coxeter case.", "revisions": [ { "version": "v1", "updated": "2020-02-13T12:16:05.000Z" } ], "analyses": { "keywords": [ "reflection subgroup", "normalizer", "hecke algebra", "finite complex reflection group", "standard basis" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable" } } }