Results 51 to 60 of about 1,448 (102)

Four-dimensional Riemannian product manifolds with circulant structures

, 2019
A 4-dimensional Riemannian manifold equipped with an additional tensor structure, whose fourth power is the identity, is considered. This structure has a circulant matrix with respect to some basis, i.e.
Dokuzova, Iva
core  

Invariant and non-invariant almost complex structures on compact quotients of Lie groups

Complex Manifolds
In this article, we briefly survey the classical problem of understanding which Lie algebras admit a complex structure, put in the broader perspective of almost complex structures with special properties.
Sillari Lorenzo, Tomassini Adriano
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

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

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 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

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 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

Commuting Conditions of the k-th Cho operator with the structure Jacobi operator of real hypersurfaces in complex space forms

Open Mathematics, 2015
In this paper three dimensional real hypersurfaces in non-flat complex space forms whose k-th Cho operator with respect to the structure vector field ξ commutes with the structure Jacobi operator are classified.
Panagiotidou Konstantina, Pérez Juan de Dios   +1 more
doaj   +1 more source