Proper action on a homogeneous space of reductive type.
Proper homothetic vector fields in Bianchi type-I space-time.
Properties of a hypothetical exotic complex structure on
We consider almost-complex structures on whose total Chern classes differ from that of the standard (integrable) almost-complex structure. E. Thomas established the existence of many such structures. We show that if there exists an “exotic” integrable almost-complex structures, then the resulting complex manifold would have specific Hodge numbers which do not vanish. We also give a necessary condition for the nondegeneration of the Frölicher spectral sequence at the second level.
Properties of complete non-compact Kähler surfaces of negative Ricci curvature.
Properties of distance functions on convex surfaces and applications
If is a convex surface in a Euclidean space, then the squared intrinsic distance function is DC (d.c., delta-convex) on in the only natural extrinsic sense. An analogous result holds for the squared distance function from a closed set . Applications concerning -boundaries (distance spheres) and ambiguous loci (exoskeletons) of closed subsets of a convex surface are given.
Properties of hypersurfaces which are characteristic for spaces of constant curvature
Properties of Kählerian twistor-spinors and vanishing theorems.
Properties of operators occurring in the Penrose transform
It is shown that operators occurring in the classical Penrose transform are differential. These operators are identified depending on line bundles over the twistor space.
Propriétés de Lefschetz dans la cohomologie de certaines variétés arithmétiques : le cas des surfaces modulaires de Hilbert
Propriétés de mélange du flot des chambres de Weyl des groupes de Ping-Pong
Dans cet article, nous étudions le flot des chambres de Weyl d’une large classe de sous-groupe discrets d’un groupe de Lie semi-simple réel : les groupes de Ping-Pong. Nous montrons que ce flot est mélangeant relativement à la mesure de Patterson-Sullivan ; celle-ci étant infinie en rang , nous précisons cette propriété de mélange en explicitant sa vitesse dans le direction du vecteur de croissance du groupe.
Propriétés génériques des fonctions propres et multiplicité.
Propriétés globales de l'espace de twisteurs
We study global properties of the twistor space over an even dimensional conformally flat manifold, proving that the twistor space is Kähler if and only if the manifold is conformally equivalent to the standard -dimensional sphere ().
Proximinality in geodesic spaces.
Pseudo holomorphic curves in symplectic manifolds.
Pseudo projectively flat manifolds satisfying certain condition on the Ricci tensor.
Pseudo-Bochner curvature tensor on Hermitian manifolds
Our main purpose of this paper is to introduce a natural generalization of the Bochner curvature tensor on a Hermitian manifold provided with the Hermitian connection. We will call the pseudo-Bochner curvature tensor. Firstly, we introduce a unique tensor P, called the (Hermitian) pseudo-curvature tensor, which has the same symmetries as the Riemannian curvature tensor on a Kähler manifold. By using P, we derive a necessary and sufficient condition for a Hermitian manifold to be of pointwise...
Pseudo-Bochner-flat locally conformal Kähler submanifolds
Let M̃ be an (m+r)-dimensional locally conformal Kähler (l.c.K.) manifold and let M be an m-dimensional l.c.K. submanifold of M̃ (i.e., a complex submanifold with the induced l.c.K. structure). Assume that both M̃ and M are pseudo-Bochner-flat. We prove that if r < m, then M is totally geodesic (in the Hermitian sense) in M̃. This is the l.c.K. version of Iwatani's result for Bochner-flat Kähler submanifolds.
Pseudoconcave homogeneous surfaces.
Pseudo-convexité locale dans les variétés kahlériennes
Soit un ouvert relativement compact et localement pseudo-convexe de la variété analytique .Alors,1) Si le fibré tangent est positif, est -convexe.2) Si admet une fonction strictement plurisousharmonique, est de Stein.3) Si est l’espace total d’un morphisme de Stein à base de Stein, est de Stein.
Pseudo-Hermitian Symmetric Spaces