Results 31 to 40 of about 47,687 (176)

Anti-Invariant Semi-Riemannian Submersions from Almost Para-Hermitian Manifolds

Journal of Function Spaces and Applications, 2013
We introduce anti-invariant semi-Riemannian submersions from almost para-Hermitian manifolds onto semi-Riemannian manifolds. We give an example, investigate the geometry of foliations which are arisen from the definition of a semi-Riemannian submersion ...
Yılmaz Gündüzalp
doaj   +1 more source

Ricci curvatures of contact Riemannian manifolds [PDF]

Tohoku Mathematical Journal, 1988
It is not known whether there exist contact Riemannian manifolds of constant \(\phi\)-sectional curvature which are not Sasakian. The author proves that the Ricci curvature of a contact Riemannian manifold of constant \(\phi\)-sectional curvature satisfies an inequality, from which a condition for such a manifold to be Sasakian is obtained.
openaire   +3 more sources

Prescribing the curvature of Riemannian manifolds with boundary [PDF]

Calculus of Variations and Partial Differential Equations, 2019
Let $M$ be a compact connected surface with boundary. We prove that the signal condition given by the Gauss-Bonnet theorem is necessary and sufficient for a given smooth function $f$ on $\partial M$ (resp. on $M$) to be geodesic curvature of the boundary (resp. the Gauss curvature) of some flat metric on $M$ (resp. metric on $M$ with geodesic boundary).
Tiarlos Cruz, Feliciano Vitorio
openaire   +3 more sources

Some results on almost paracontact paracomplex Riemannian manifolds

AIMS Mathematics
In this study, a class of Riemannian almost product manifolds is obtained by the warped product of almost paracontact paracomplex Riemannian manifolds with $ \mathbb{R} $. The curvature properties of the almost product manifolds are studied. Then, normal
Nülifer Özdemir, Şirin Aktay, Mehmet Solgun   +2 more
doaj   +1 more source

A Kähler Einstein structure on the tangent bundle of a space form

International Journal of Mathematics and Mathematical Sciences, 2001
We obtain a Kähler Einstein structure on the tangent bundle of a Riemannian manifold of constant negative curvature. Moreover, the holomorphic sectional curvature of this Kähler Einstein structure is constant.
Vasile Oproiu
doaj   +1 more source

Comparison Theorems on Weighted Finsler Manifolds and Spacetimes with ϵ-Range

Analysis and Geometry in Metric Spaces, 2022
We establish the Bonnet–Myers theorem, Laplacian comparison theorem, and Bishop–Gromov volume comparison theorem for weighted Finsler manifolds as well as weighted Finsler spacetimes, of weighted Ricci curvature bounded below by using the weight function.
Lu Yufeng, Minguzzi Ettore, Ohta Shin-ichi   +2 more
doaj   +1 more source

First Natural Connection on Riemannian Π-Manifolds

Mathematics, 2023
A natural connection with torsion is defined, and it is called the first natural connection on the Riemannian Π-manifold. Relations between the introduced connection and the Levi–Civita connection are obtained.
Hristo Manev
doaj   +1 more source

Ellipsoid‐Based Interval‐Type Uncertainty Model Updating Based on Riemannian Manifold and Gaussian Process Model

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT Modern engineering systems require advanced uncertainty‐aware model updating methods that address parameter correlations beyond conventional interval analysis. This paper proposes a novel framework integrating Riemannian manifold theory with Gaussian Process Regression (GPR) for systems governed by Symmetric Positive‐Definite (SPD) matrix ...
Yanhe Tao, Qintao Guo, Jin Zhou, Cheng Yi   +3 more
wiley   +1 more source

On Slant Riemannian Submersions For Cosymplectic Manifolds [PDF]

, 2013
In this paper we introduce slant Riemannian submersions from cosymplectic manifolds onto Riemannian manifolds. We obtain some results on slant Riemannian submersions of a cosymplectic manifolds.
Erken, İrem Küpeli, Murathan, Cengizhan   +1 more
core  

Blocking light in compact Riemannian manifolds

, 2006
We study compact Riemannian manifolds for which the light between any pair of points is blocked by finitely many point shades. Compact flat Riemannian manifolds are known to have this finite blocking property.
Benjamin Schmidt, Berger, Besse, Brown, Davis, do Carmo, Gutkin, Jean-François Lafont, Mañé, Monteil, Pesin, Sabourau, Santaló   +12 more
core   +1 more source