{ "id": "0805.3018", "version": "v2", "published": "2008-05-20T07:35:46.000Z", "updated": "2017-07-14T17:12:25.000Z", "title": "Hyperbolic Weyl groups and the four normed division algebras", "authors": [ "Alex J. Feingold", "Axel Kleinschmidt", "Hermann Nicolai" ], "comment": "56 pages, 21 figures. Revised to: (1) Correct typo in formula (4.33), (2) Correct error in Prop. 15, (3) Add references [44] and [45], (4) Match other corrections in the published version", "journal": "J.Algebra 322:1295-1339 (2009)", "doi": "10.1016/j.jalgebra.2009.05.006", "categories": [ "math.RT", "hep-th", "math.GR" ], "abstract": "We study the Weyl groups of hyperbolic Kac-Moody algebras of `over-extended' type and ranks 3, 4, 6 and 10, which are intimately linked with the four normed division algebras K=R,C,H,O, respectively. A crucial role is played by integral lattices of the division algebras and associated discrete matrix groups. Our findings can be summarized by saying that the even subgroups, W^+, of the Kac-Moody Weyl groups, W, are isomorphic to generalized modular groups over K for the simply laced algebras, and to certain finite extensions thereof for the non-simply laced algebras. This hints at an extended theory of modular forms and functions.", "revisions": [ { "version": "v1", "updated": "2008-05-20T07:35:46.000Z", "comment": "56 pages, 21 figures", "journal": "J.Algebra 322:1295-1339,2009" }, { "version": "v2", "updated": "2017-07-14T17:12:25.000Z" } ], "analyses": { "subjects": [ "17A35", "17B67", "20F55", "11F06" ], "keywords": [ "normed division algebras", "hyperbolic weyl groups", "hyperbolic kac-moody algebras", "associated discrete matrix groups", "kac-moody weyl groups" ], "tags": [ "journal article" ], "publication": { "publisher": "Elsevier" }, "note": { "typesetting": "TeX", "pages": 56, "language": "en", "license": "arXiv", "status": "editable", "inspire": 789041, "adsabs": "2008arXiv0805.3018F" } } }