{ "id": "2011.13003", "version": "v1", "published": "2020-11-25T20:09:11.000Z", "updated": "2020-11-25T20:09:11.000Z", "title": "Faithfulness of simple 2-representations of $\\mathfrak{sl}_2$", "authors": [ "Laurent Vera" ], "comment": "24 pages", "categories": [ "math.RT" ], "abstract": "Let $\\mathcal U$ be the 2-category associated with $\\mathfrak{sl}_2$. We prove that a complex of 1-morphisms of $\\mathcal U$ is null-homotopic if and only if its image in every simple 2-representation is null-homotopic. Under mild boundedness assumptions, we prove that it actually suffices for the image in the simple 2-representations to be acyclic. We apply this result to the study of the Rickard complex $\\Theta$ categorifying the action of the simple reflection of $\\mathrm{SL}_2$. We prove that $\\Theta$ is invertible in the homotopy category of $\\U$, and that there is a homotopy equivalence $\\Theta E \\simeq F\\Theta[-1]$.", "revisions": [ { "version": "v1", "updated": "2020-11-25T20:09:11.000Z" } ], "analyses": { "keywords": [ "faithfulness", "mild boundedness assumptions", "homotopy equivalence", "null-homotopic", "rickard complex" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable" } } }