{ "id": "math/0403203", "version": "v2", "published": "2004-03-12T00:32:56.000Z", "updated": "2005-08-23T22:34:20.000Z", "title": "Representation rings of Lie superalgebras", "authors": [ "Gregory D. Landweber" ], "comment": "36 pages, 1 figure, uses Payl Taylor's diagrams package. Updated with minor corrections", "journal": "K-Theory 36 (2005), no. 1-2, 115-168", "categories": [ "math.RT", "math.KT" ], "abstract": "Given a Lie superalgebra \\g, we introduce several variants of the representation ring, built as subrings and quotients of the ring R_{\\Z_2}(\\g) of virtual \\g-supermodules (up to even isomorphisms). In particular, we consider the ideal R_{+}(\\g) of virtual \\g-supermodules isomorphic to their own parity reversals, as well as an equivariant K-theoretic super representation ring SR(\\g) on which the parity reversal operator takes the class of a virtual \\g-supermodule to its negative. We also construct representation groups built from ungraded \\g-modules, as well as degree-shifted representation groups using Clifford modules. The full super representation ring SR^{*}(\\g), including all degree shifts, is then a \\Z_{2}-graded ring in the complex case and a \\Z_{8}-graded ring in the real case. Our primary result is a six-term periodic exact sequence relating the rings R^{*}_{\\Z_2}(\\g), R^{*}_{+}(\\g), and SR^{*}(\\g). We first establish a version of it working over an arbitrary (not necessarily algebraically closed) field of characteristic 0. In the complex case, this six-term periodic long exact sequence splits into two three-term sequences, which gives us additional insight into the structure of the complex super representation ring SR^{*}(\\g). In the real case, we obtain the expected 24-term version, as well as a surprising six-term version of this periodic exact sequence.", "revisions": [ { "version": "v2", "updated": "2005-08-23T22:34:20.000Z" } ], "analyses": { "subjects": [ "19A22", "19L47", "17B10", "16E20" ], "keywords": [ "lie superalgebra", "periodic exact sequence relating", "k-theoretic super representation ring", "periodic long exact sequence splits", "six-term periodic long exact sequence" ], "tags": [ "research tool", "journal article" ], "note": { "typesetting": "TeX", "pages": 36, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......3203L" } } }