Minimal CR-submanifolds of a six-dimensional sphere.
Modular vector fields and Batalin-Vilkovisky algebras
We show that a modular class arises from the existence of two generating operators for a Batalin-Vilkovisky algebra. In particular, for every triangular Lie bialgebroid (A,P) such that its top exterior power is a trivial line bundle, there is a section of the vector bundle A whose -cohomology class is well-defined. We give simple proofs of its properties. The modular class of an orientable Poisson manifold is an example. We analyse the relationships between generating operators of the Gerstenhaber...
Moisezon Spaces and Almost Positive Coherent Sheaves.
Multiplicity-free complex manifolds.
Natural 2-forms on the tangent bundle of a Riemannian manifold
Natural diagonal Riemannian almost product and para-Hermitian cotangent bundles
We obtain the natural diagonal almost product and locally product structures on the total space of the cotangent bundle of a Riemannian manifold. Studying the compatibility and the anti-compatibility relations between the determined structures and a natural diagonal metric, we find the Riemannian almost product (locally product) and the (almost) para-Hermitian cotangent bundles of natural diagonal lift type. Finally, we prove the characterization theorem for the natural diagonal (almost) para-Kählerian...
Natural tensor fields of type on the tangent and cotangent bundles of a Fedosov manifold.
Natural transformations of second tangent and cotangent functors
New aspects on CR-structures of codimension 2 on hypersurfaces of Sasakian manifolds
We introduce a torsion free linear connection on a hypersurface in a Sasakian manifold on which we have defined in natural way a -structure of -codimension 2. We study the curvature properties of this connection and we give some interesting examples.
New hyper-Käahler structures on tangent bundles
Let be an almost Hermitian manifold, then the tangent bundle carries a class of naturally defined almost hyper-Hermitian structures . In this paper we give conditions under which these almost hyper-Hermitian structures are locally conformal hyper-Kähler. As an application, a family of new hyper-structures is obtained on the tangent bundle of a complex space form. Furthermore, by restricting these almost hyper-Hermitian structures on the unit tangent sphere bundle , we obtain a class of almost...
Nilpotent complex structures.
Este artículo presenta un panorama de algunos resultados recientes sobre estructuras complejas nilpotentes J definidas sobre nilvariedades compactas. Tratamos el problema de clasificación de nilvariedades compactas que admiten una tal J, el estudio de un modelo minimal de Dolbeault y su formalidad, y la construcción de estructuras complejas nilpotentes para las cuales la sucesión espectral de Frölicher no colapsa en el segundo término.
Noeuds et structures de contact en dimension 3
Non-associative geometry and discrete structure of spacetime
A new mathematical theory, non-associative geometry, providing a unified algebraic description of continuous and discrete spacetime, is introduced.
Nonlinear connections and semisprays on tangent manifolds.
Nonlinear connections on dual Lie algebroids.
Nonstandard uniformized conformal structures on hyperbolic manifolds.
Normal almost contact metric manifolds of dimension three
Normal anti-invariant submanifolds of paraquaternionic Kähler manifolds.
Normal form of the NK-curvature operators
Notes on semi-symmetric connections on spaces endowed with Weyl -structures.