{ "id": "2312.16766", "version": "v1", "published": "2023-12-28T01:24:31.000Z", "updated": "2023-12-28T01:24:31.000Z", "title": "Jordan algebras and weight modules", "authors": [ "Michael Lau", "Olivier Mathieu" ], "comment": "18 pages", "categories": [ "math.RT", "math.RA" ], "abstract": "We consider bounded weight modules for the universal central extension ${\\mathfrak{sl}}_2(J)$ of the Tits-Kantor-Koecher algebra of a unital Jordan algebra $J$. Universal objects called Weyl modules are introduced and studied, and a combinatorial dominance criterion is given for analogues of highest weights. Specializing $J$ to the free Jordan algebra $J(r)$ of rank $r$, the category $\\mathcal{C}^{fin}$ of finite-dimensional $\\mathbb{Z}$-graded ${\\mathfrak{sl}}_2(J)$-modules shares many properties with the representation theory of algebraic groups. Using a deep result of Zelmanov, we show that this subcategory admits Weyl modules. By analogy, we conjecture that $\\mathcal{C}^{fin}$ is a highest weight category. The resulting homological properties would then imply cohomological vanishing results previously conjectured as a way of determining graded dimensions of free Jordan algebras.", "revisions": [ { "version": "v1", "updated": "2023-12-28T01:24:31.000Z" } ], "analyses": { "subjects": [ "17B10", "17B60", "17C05", "17C50" ], "keywords": [ "free jordan algebra", "subcategory admits weyl modules", "universal central extension", "combinatorial dominance criterion", "unital jordan algebra" ], "note": { "typesetting": "TeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable" } } }