Contact structures on (n-1)-connected (2n+1)-manifolds
Contact topology and the structure of 5-manifolds with
We prove a structure theorem for closed, orientable 5-manifolds with fundamental group and second Stiefel-Whitney class equal to zero on . This structure theorem is then used to construct contact structures on such manifolds by applying contact surgery to fake projective spaces and certain -quotients of .
Convexité en topologie de contact.
Corrections to "L2 -characteristic classes of Maslov–Trofimov of hamiltonian systems on the Lie algebra of the upper triangular matrices" (Fund. Math. 156 (1998), 99–110)
Cosymplectic and α-cosymplectic Lie algebras
Courbes pseudo-holomorphes équisingulières en dimension 4
Covariant star-products
CR structures on real hypersurfaces of a complex projective space.
CR submanifolds of maximal CR dimension in complex manifolds
The aim of this paper is to investigate n-dimensional real submanifolds of complex manifolds in the case when the maximal holomorphic tangent space is (n-1)-dimensional. In particular, we give some examples and we consider the Levi form on these submanifolds, especially when the ambient space is a complex space form. Moreover, we show that on some remarkable class of real hypersurfaces of complex space forms, the Levi form cannot vanish identically.
Critical points at infinity in the variational calculus
CR-structure on Seifert manifolds.
CR-warped product submanifolds of nearly Kaehler manifolds.
Curiosités Lagrangiennes en dimension 4
Dans ce texte, on définit, pour les immersions lagrangiennes de variétés fermées dans , une notion d’aire symplectique enlacée. Puis on construit, dans le cas , un certain nombre de surfaces lagrangiennes enlaçant une aire infinie. Dans le cas des surfaces exactes, elles ont le minimum de points doubles possible permis par la théorie (sauf la sphère), c’est-à-dire moins que prévu par quelques conjectures.
Curvature identifies on Hermite manifolds
Curvature properties of a semi-symmetric metric connection on S-manifolds
In this study, S-manifolds endowed with a semi-symmetric metric connection naturally related with the S-structure are considered and some curvature properties of such a connection are given. In particular, the conditions of semi-symmetry, Ricci semi-symmetry and Ricci-projective semi-symmetry of this semi-symmetric metric connection are investigated.
Curvature properties of -natural contact metric structures on unit tangent sphere bundles.
Curvature properties of φ-null Osserman Lorentzian S-manifolds
We expound some results about the relationships between the Jacobi operators with respect to null vectors on a Lorentzian S-manifold and the Jacobi operators with respect to particular spacelike unit vectors. We study the number of the eigenvalues of such operators on Lorentzian S-manifolds satisfying the φ-null Osserman condition, under suitable assumptions on the dimension of the manifold. Then, we provide in full generality a new curvature characterization for Lorentzian S-manifolds and we use...
Curvature Tensor Of Pseudo Metric Semi-Symmetric Connexions In An Almost Contact Metric Mainfold
Curvature tensor of pseudo metric semi-symmetric connexions in an almost contact metric manifold.
Curvature tensors and Ricci solitons with respect to Zamkovoy connection in anti-invariant submanifolds of trans-Sasakian manifold
The present paper deals with the study of some properties of anti-invariant submanifolds of trans-Sasakian manifold with respect to a new non-metric affine connection called Zamkovoy connection. The nature of Ricci flat, concircularly flat, -projectively flat, -projectively flat, --projectively flat, pseudo projectively flat and -pseudo projectively flat anti-invariant submanifolds of trans-Sasakian manifold admitting Zamkovoy connection are discussed. Moreover, Ricci solitons on Ricci flat,...