{ "id": "2008.10999", "version": "v1", "published": "2020-08-25T13:38:50.000Z", "updated": "2020-08-25T13:38:50.000Z", "title": "On Ext-Quivers of Blocks of Weight Two for Symmetric Groups", "authors": [ "Susanne Danz", "Karin Erdmann" ], "comment": "47 pages (of this, 17 pages is an appendix)", "categories": [ "math.RT" ], "abstract": "In this paper we investigate blocks of symmetric groups of weight 2 over fields of odd characteristic $p$. We develop an algorithm that relates the quivers of two such blocks forming a $(2:1)$ pair, as introduced by Scopes. We then apply the algorithm to blocks whose $p$-cores are hook partitions, in order to explicitly determine the quivers of these blocks. As a consequence we conclude that two $p$-blocks $B_1$ and $B_2$ of symmetric groups of weight $2$ whose $p$-cores are hook partitions are Morita equivalent if and only if $B_2$ or its conjugate block is in the same Scopes class as $B_1$.", "revisions": [ { "version": "v1", "updated": "2020-08-25T13:38:50.000Z" } ], "analyses": { "subjects": [ "29C20", "20C30", "16D90" ], "keywords": [ "symmetric groups", "ext-quivers", "hook partitions", "conjugate block", "odd characteristic" ], "note": { "typesetting": "TeX", "pages": 47, "language": "en", "license": "arXiv", "status": "editable" } } }