{ "id": "1812.06711", "version": "v1", "published": "2018-12-17T11:30:46.000Z", "updated": "2018-12-17T11:30:46.000Z", "title": "Steinberg squares and tensor products of tilting modules with simple modules", "authors": [ "Paul Sobaje" ], "comment": "8 pages, feedback very welcome", "categories": [ "math.RT" ], "abstract": "Let $G$ be a simple and simply connected algebraic group over an algebraically closed field $\\Bbbk$ of characteristic $p>0$. We establish an isomorphism of $G$-modules between a direct sum of modules $\\text{St} \\otimes \\text{St}$ and a direct sum of tensor products of simple modules of restricted highest weight with tilting modules that are projective over the Frobenius kernel of $G$. This isomorphism holds precisely when Donkin's Tilting Module Conjecture does, and thus can be seen as providing a $G$-module theoretic characterization of this conjecture.", "revisions": [ { "version": "v1", "updated": "2018-12-17T11:30:46.000Z" } ], "analyses": { "keywords": [ "simple modules", "tensor products", "steinberg squares", "direct sum", "module theoretic characterization" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable" } } }