{ "id": "1703.07732", "version": "v1", "published": "2017-03-22T16:26:27.000Z", "updated": "2017-03-22T16:26:27.000Z", "title": "The realization problem for Jørgensen numbers", "authors": [ "Yasushi Yamashita", "Ryosuke Yamazaki" ], "comment": "13 pages, 5 figures", "categories": [ "math.GT" ], "abstract": "Let G be a two generator subgroup of PSL(2,C). The Jorgensen number J(G) of G is defined by J(G)=inf{ |tr^2 A-4|+|tr[A,B]-2| ; G=}. If G is a non-elementary Kleinian group, then J(G) >= 1. This inequality is called Jorgensen's inequality. In this paper, we show that, for any r >= 1, there exists a non-elementary Kleinian group whose Jorgensen number is equal to r. This answers a question posed by Oichi and Sato. We also present our computer generated picture which estimates Jorgensen numbers from above in the diagonal slice of Schottky space.", "revisions": [ { "version": "v1", "updated": "2017-03-22T16:26:27.000Z" } ], "analyses": { "subjects": [ "30F40" ], "keywords": [ "realization problem", "jørgensen numbers", "non-elementary kleinian group", "estimates jorgensen numbers", "jorgensens inequality" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }