{ "id": "2209.12566", "version": "v1", "published": "2022-09-26T10:33:50.000Z", "updated": "2022-09-26T10:33:50.000Z", "title": "Dirac cohomology for the BGG category $\\mathcal{O}$", "authors": [ "Spyridon Afentoulidis-Almpanis" ], "categories": [ "math.RT" ], "abstract": "We study Dirac cohomology $H_D^{\\mathfrak{g},\\mathfrak{h}}(M)$ for modules belonging to category $\\mathcal{O}$ of a finite dimensional complex semisimple Lie algebra. We prove Vogan's conjecture, a nonvanishing result for $H_D^{\\mathfrak{g},\\mathfrak{h}}(M)$ while we show that in the case of a Hermitian symmetric pair $(\\mathfrak{g},\\mathfrak{k})$ and an irreducible unitary module $M\\in\\mathcal{O}$, Dirac cohomology coincides with the nilpotent Lie algebra cohomology with coefficients in $M$. In the last part, we show that the higher Dirac cohomology and index introduced by Pand\\v{z}i\\'c and Somberg satisfy nice homological properties for $M\\in\\mathcal{O}$.", "revisions": [ { "version": "v1", "updated": "2022-09-26T10:33:50.000Z" } ], "analyses": { "subjects": [ "17B10", "17B20", "17B56" ], "keywords": [ "dirac cohomology", "bgg category", "finite dimensional complex semisimple lie", "dimensional complex semisimple lie algebra", "somberg satisfy nice homological properties" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }