{ "id": "math/0307383", "version": "v1", "published": "2003-07-30T05:13:28.000Z", "updated": "2003-07-30T05:13:28.000Z", "title": "Representations of wreath products on cohomology of De Concini-Procesi compactifications", "authors": [ "Anthony Henderson" ], "comment": "38 pages", "journal": "Intern. Math. Res. Notices 2004:20 (2004), 983-1021", "categories": [ "math.RT", "math.AG", "math.CO" ], "abstract": "The wreath product W(r,n) of the cyclic group of order r and the symmetric group S_n acts on the corresponding projective hyperplane complement, and on its wonderful compactification as defined by De Concini and Procesi. We give a formula for the characters of the representations of W(r,n) on the cohomology groups of this compactification, extending the result of Ginzburg and Kapranov in the r=1 case. As a corollary, we get a formula for the Betti numbers which generalizes the result of Yuzvinsky in the r=2 case. Our method involves applying to the nested-set stratification a generalization of Joyal's theory of tensor species, which includes a link between polynomial functors and plethysm for general r. We also give a new proof of Lehrer's formula for the representations of W(r,n) on the cohomology groups of the hyperplane complement.", "revisions": [ { "version": "v1", "updated": "2003-07-30T05:13:28.000Z" } ], "analyses": { "subjects": [ "20F55", "14D99", "05A15" ], "keywords": [ "wreath product", "concini-procesi compactifications", "representations", "cohomology groups", "symmetric group" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 38, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2003math......7383H" } } }