Results 61 to 70 of about 130 (124)

Canonical submersions in nearly Kähler geometry

Complex Manifolds
We explore submersions introduced by reducible holonomy representations of connections with parallel skew torsion. A submersion theorem extending previous, less general, results is given. As our main application, we show that parallel 3-(α,δ)\left(\alpha
Stecker Leander
doaj   +1 more source

A dimensional restriction for a class of contact manifolds

Demonstratio Mathematica, 2017
In this work we consider a class of contact manifolds (M, η) with an associated almost contact metric Structure (ϕ, ξ, η, g). This class contains, for example, nearly cosymplectic manifolds and the manifolds in the class C9 ⊕ C10 defined by Chinea and ...
Loiudice Eugenia
doaj   +1 more source

Deformations of neutral almost Kähler manifolds

, 2006
Common deformations for neutral pseudoriemann manifolds with compatible almost complex structure and closed fundamental two-form are considered. An example of nontrivial common deformation on the cylindrical Heisenberg group with invariant almost complex
Petrov, Kalin P., Apostolova, Lilia Nik.
core  

Purity and hybridness of two tensors on a real hypersurface in complex projective space

Open Mathematics
On a real hypersurface MM in complex projective space, we can define two tensor fields of type (1, 2), AF(k){A}_{F}^{\left(k)} and AT(k){A}_{T}^{\left(k)}, associated with the shape operator AA of the real hypersurface, for any nonnull real number kk ...
Pérez Juan de Dios, Pérez-López David
doaj   +1 more source

Generalized almost paracontact structures

Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2015
The notion of generalized almost paracontact structure on the generalized tangent bundle TM ⊕ T* M is introduced and its properties are investigated.
Blaga Adara M., Ida Cristian
doaj   +1 more source

On the partial parallelizable manifolds and associated invariants

Annals of the West University of Timisoara: Mathematics and Computer Science
Our idea is to use the global diffeomorphism group G (M) to study certain properties of differentiable manifolds endowed with global vector fields. We define a partial parallelizable manifold (p.p.m.) as a couple (M, ρp), where ρp is a global partial ...
Apreutesei Costache
doaj   +1 more source

On the Kähler-likeness on almost Hermitian manifolds

Complex Manifolds, 2019
We define a Kähler-like almost Hermitian metric. We will prove that on a compact Kähler-like almost Hermitian manifold (M2n, J, g), if it admits a positive ∂ ̄∂-closed (n − 2, n − 2)-form, then g is a quasi-Kähler metric.
Kawamura Masaya
doaj   +1 more source

Хармонични собствени почти комплексни структури върху 4-многообразия на Уокър

, 2014
[Davidov Johann; Давидов Йохан]; [Ul Haq Absar; Ул Хак Абсар]; [Mushkarov Oleg; Muškarov Oleg; Мушкаров Олег]Every Walker 4-manifold M, endowed with a canonical neutral metric, admits a specific almost complex structure called proper.
Ul Haq, Absar, Davidov, Johann, Mushkarov, Oleg   +2 more
core  

On tangent bundles of Walker four-manifolds

Open Mathematics
The aim of this study is to explore the complete lifts of almost Norden structures on tangent bundles of Walker four-manifolds. Furthermore, we examine the integrability conditions of the complete lifts JC{J}^{C} of the proper almost complex structure ...
Çayir Haşim, Güler Erkan, Köseoğlu Gökhan   +2 more
doaj   +1 more source

Almost Kenmotsu manifolds with conformal Reeb foliation

, 2011
We consider almost Kenmotsu manifolds with conformal Reeb foliation. We prove that such a foliation produces harmonic morphisms,we study the k-nullity distributions and we discuss the isometric immersion of such a manifold M as hypersurface in a real ...
PASTORE, Anna Maria, SALTARELLI V.
core