arXiv math/05072722005-07-16math.CVmath.DG

The CR structure of minimal orbits in complex flag manifolds

Andrea Altomani, Costantino Medori, Mauro Nacinovich

备注：: AMS-TeX, 44 pages v2: minor revision
发表信息：: J. Lie Theory 16, No. 3, 483-530 (2006)

英文摘要：

Let Ĝ be a complex semisimple Lie group, Q a parabolic subgroup and G a real form of Ĝ. The flag manifold Ĝ/Q decomposes into finitely many G-orbits; among them there is exactly one orbit of minimal dimension, which is compact. We study these minimal orbits from the point of view of CR geometry. In particular we characterize those minimal orbits that are of finite type and satisfy various nondegeneracy conditions, compute their fundamental group and describe the space of their global CR functions. Our main tool are parabolic CR algebras, which give an infinitesimal description of the CR structure of minimal orbits.

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