{ "id": "0807.1601", "version": "v4", "published": "2008-07-10T09:19:54.000Z", "updated": "2013-12-09T08:32:25.000Z", "title": "The complexifications of pseudo-Riemannian manifolds and anti-Kaehler geometry", "authors": [ "Naoyuki Koike" ], "comment": "25pages", "categories": [ "math.DG" ], "abstract": "In this paper, we first define the complexification of a real analytic map between real analytic Koszul manifolds and show that the complexified map is the holomorphic extension of the original map. Next we define an anti-Kaehler metric compatible with the adapted complex structure on the complexification of a real analytic pseudo-Riemannian manifold. In particular, for a pseudo-Riemannian homogeneous space, we define another complexification and a (complete) anti-Kaehler metric on the complexification. One of main purposes of this paper is to find the interesting relation between these two complexifications (equipped with the anti-Kaehler metrics) of a pseudo-Riemannian homogeneous space. Another of main purposes of this paper is to show that almost all principal orbits of some isometric action on the first complexification (equipped with the anti-Kaehler metric) of a semi-simple pseudo-Riemannian symmetric space are curvature-adapted isoparametric submanifolds with flat section in the sense of this paper.", "revisions": [ { "version": "v4", "updated": "2013-12-09T08:32:25.000Z" } ], "analyses": { "subjects": [ "53C56", "53C42" ], "keywords": [ "complexification", "anti-kaehler geometry", "anti-kaehler metric", "pseudo-riemannian homogeneous space", "real analytic pseudo-riemannian manifold" ], "note": { "typesetting": "TeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0807.1601K" } } }