{ "id": "math/0607401", "version": "v2", "published": "2006-07-18T03:47:31.000Z", "updated": "2007-03-11T22:46:51.000Z", "title": "Generalized geometry, equivariant $\\bar{\\partial}\\partial$-lemma, and torus actions", "authors": [ "Yi Lin" ], "comment": "to appear in the Journal of Geometry and Physics, 27 pages, a few typos and small mistakes corrected, added a few more references", "doi": "10.1016/j.geomphys.2007.03.004", "categories": [ "math.DG", "hep-th", "math-ph", "math.MP", "math.SG" ], "abstract": "In this paper we first consider the Hamiltonian action of a compact connected Lie group on an $H$-twisted generalized complex manifold $M$. Given such an action, we define generalized equivariant cohomology and generalized equivariant Dolbeault cohomology. If the generalized complex manifold $M$ satisfies the $\\bar{\\partial}\\partial$-lemma, we prove that they are both canonically isomorphic to $(S\\g^*)^G\\otimes H_H(M)$, where $(S\\g^*)^G$ is the space of invariant polynomials over the Lie algebra $\\g$ of $G$, and $H_H(M)$ is the $H$-twisted cohomology of $M$. Furthermore, we establish an equivariant version of the $\\bar{\\partial}\\partial$-lemma, namely $\\bar{\\partial}_G\\partial$-lemma, which is a direct generalization of the $d_G\\delta$-lemma for Hamiltonian symplectic manifolds with the Hard Lefschetz property. Second we consider the torus action on a compact generalized K\\\"ahler manifold which preserves the generalized K\\\"ahler structure and which is equivariantly formal. We prove a generalization of a result of Carrell and Lieberman in generalized K\\\"ahler geometry. We then use it to compute the generalized Hodge numbers for non-trivial examples of generalized K\\\"ahler structures on $\\C\\P^n$ and $\\CP^n$ blown up at a fixed point.", "revisions": [ { "version": "v2", "updated": "2007-03-11T22:46:51.000Z" } ], "analyses": { "subjects": [ "53C15", "53C55", "53D20" ], "keywords": [ "torus action", "generalized geometry", "generalized complex manifold", "compact connected lie group", "generalized equivariant dolbeault cohomology" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 27, "language": "en", "license": "arXiv", "status": "editable", "inspire": 737082 } } }