Nous étudions l’action d’un groupe réel-réductif sur une sous-variété réel-analytique d’une variété kählérienne. Nous supposons que l’action de peut être prolongée en une action holomorphe du groupe complexifié sur cette variété kählérienne telle que l’action d’un sous-groupe maximal compact de soit hamiltonienne. L’application moment induit une application gradient . Nous montrons que sépare presque les orbites de si et seulement si un sous-groupe minimal parabolique de possède une orbite ouverte dans . Ce résultat généralise la caractérisation de Brion des variétés kählériennes sphériques qui admettent une application moment.
We study the action of a real-reductive group on a real-analytic submanifold of a Kähler manifold. We suppose that the action of extends holomorphically to an action of the complexified group on this Kähler manifold such that the action of a maximal compact subgroup is Hamiltonian. The moment map induces a gradient map . We show that almost separates the –orbits if and only if a minimal parabolic subgroup of has an open orbit. This generalizes Brion’s characterization of spherical Kähler manifolds with moment maps.
@article{AIF_2010__60_6_2235_0, author = {Miebach, Christian and St\"otzel, Henrik}, title = {Spherical gradient manifolds}, journal = {Annales de l'Institut Fourier}, volume = {60}, year = {2010}, pages = {2235-2260}, doi = {10.5802/aif.2582}, zbl = {1214.32007}, mrnumber = {2791656}, language = {en}, url = {http://dml.mathdoc.fr/item/AIF_2010__60_6_2235_0} }
Miebach, Christian; Stötzel, Henrik. Spherical gradient manifolds. Annales de l'Institut Fourier, Tome 60 (2010) pp. 2235-2260. doi : 10.5802/aif.2582. http://gdmltest.u-ga.fr/item/AIF_2010__60_6_2235_0/
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