{ "id": "2207.12946", "version": "v1", "published": "2022-07-26T14:51:18.000Z", "updated": "2022-07-26T14:51:18.000Z", "title": "Topology of almost complex structures on six-manifolds", "authors": [ "Gustavo Granja", "Aleksandar Milivojevic" ], "comment": "20 pages, comments very welcome", "categories": [ "math.DG", "math.AT" ], "abstract": "We study the space of (orthogonal) almost complex structures on closed six-dimensional manifolds as the space of sections of the twistor space for a given metric. For a connected six-manifold with vanishing first Betti number, we express the space of almost complex structures as a quotient of the space of sections of a seven-sphere bundle over the manifold by a circle action, and then use this description to compute the rational homotopy theoretic minimal model of the components that satisfy a certain Chern number condition. We further obtain a formula for the homological intersection number of two sections of the twistor space in terms of the Chern classes of the corresponding almost complex structures.", "revisions": [ { "version": "v1", "updated": "2022-07-26T14:51:18.000Z" } ], "analyses": { "subjects": [ "32Q60", "53C27", "53C28", "55P62" ], "keywords": [ "complex structures", "six-manifold", "rational homotopy theoretic minimal model", "twistor space", "vanishing first betti number" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable" } } }