{ "id": "1907.10089", "version": "v1", "published": "2019-07-19T18:42:54.000Z", "updated": "2019-07-19T18:42:54.000Z", "title": "Representation ring of Levi subgroups versus cohomology ring of flag varieties II", "authors": [ "Shrawan Kumar", "Sean Rogers" ], "comment": "19 pages. arXiv admin note: text overlap with arXiv:1508.06826", "categories": [ "math.RT", "math.AT", "math.GR" ], "abstract": "For any reductive group G and a parabolic subgroup P with its Levi subgroup L, the first author in [Ku2] introduced a ring homomorphism $ \\xi^P_\\lambda: Rep^\\mathbb{C}_{\\lambda-poly}(L) \\to H^*(G/P, \\mathbb{C})$, where $ Rep^\\mathbb{C}_{\\lambda-poly}(L)$ is a certain subring of the complexified representation ring of L (depending upon the choice of an irreducible representation $V(\\lambda)$ of G with highest weight $\\lambda$). In this paper we study this homomorphism for G=Sp(2n) and its maximal parabolic subgroups $P_{n-k}$ for any $1\\leq k\\leq n$ (with the choice of $V(\\lambda) $ to be the defining representation $V(\\omega_1) $ in $\\mathbb{C}^{2n}$). Thus, we obtain a $\\mathbb{C}$-algebra homomorphism $ \\xi_{n,k}: Rep^\\mathbb{C}_{\\omega_1-poly}(Sp(2k)) \\to H^*(IG(n-k, 2n), \\mathbb{C})$. Our main result asserts that $ \\xi_{n,k}$ is injective when n tends to $\\infty$ keeping k fixed. Similar results are obtained for the odd orthogonal groups.", "revisions": [ { "version": "v1", "updated": "2019-07-19T18:42:54.000Z" } ], "analyses": { "subjects": [ "17B10", "14N15", "14L35", "14M15" ], "keywords": [ "levi subgroup", "representation ring", "flag varieties", "cohomology ring", "homomorphism" ], "note": { "typesetting": "TeX", "pages": 19, "language": "en", "license": "arXiv", "status": "editable" } } }