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相关论文: On the structure of Einstein warped product semi-R…

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In this paper, we study the existence of proper warped product submanifolds in metallic (or Golden) Riemannian manifolds and we discuss about semi-invariant, semi-slant and, respectively, hemi-slant warped product submanifolds in metallic…

微分几何 · 数学 2025-08-04 Cristina E. Hretcanu , Adara M. Blaga

Given a compact Riemannian manifold $M$, we consider a warped product $\bar M = I \times_h M$ where $I$ is an open interval in $\Rr$. We suppose that the mean curvature of the fibers do not change sign. Given a positive differentiable…

微分几何 · 数学 2008-10-21 F. Andrade , J. L. Barbosa , J. H. de Lira

A. Gray presented an interesting $O\left( n\right) $ invariant decomposition of the covariant derivative of the Ricci tensor. Manifolds whose Ricci tensor satisfies the defining property of each orthogonal class are called Einstein-like…

微分几何 · 数学 2021-04-27 Hoda K. El-Sayed , Carlo Alberto Mantica , Sameh Shenawy , Noha Syied

We introduce the concept of a base conformal warped product of two pseudo-Riemannian manifolds. We also define a subclass of this structure called as a special base conformal warped product. After, we explicitly mention many of the relevant…

微分几何 · 数学 2008-08-25 Fernando Dobarro , Bulent Unal

Many classical results in relativity theory concerning spherically symmetric space-times have easy generalizations to warped product space-times, with a two-dimensional Lorentzian base and arbitrary dimensional Riemannian fibers. We first…

广义相对论与量子宇宙学 · 物理学 2017-12-20 Xinliang An , Willie Wai Yeung Wong

Let $M$ be pseudo-Riemannian homogeneous Einstein manifold of finite volume, and suppose a connected Lie group $G$ acts transitively and isometrically on $M$. In this situation, the metric on $M$ induces a bilinear form…

微分几何 · 数学 2021-06-17 Wolfgang Globke , Yuri Nikolayevsky

The purpose of this note is to provide some volume estimates for Einstein warped products similar to a classical result due to Calabi and Yau for complete Riemannian manifolds with nonnegative Ricci curvature. To do so, we make use of the…

微分几何 · 数学 2014-08-08 A. Barros , R. Batista , E. Ribeiro

We prove that complete warped product Einstein metrics with isometric bases, simply connected space form fibers, and the same Ricci curvature and dimension are isometric. In the compact case we also prove that the warping functions must be…

微分几何 · 数学 2013-02-05 Chenxu He , Peter Petersen , William Wylie

In this paper we show that an expanding or steady gradient Ricci soliton warped product $B^n\times_f F^m$, $m>1$, whose warping function $f$ reaches both maximum and minimum must be a Riemannian product. Moreover, we present a necessary and…

微分几何 · 数学 2021-05-04 F. E. S. Feitosa , A. A. Freitas Filho , J. N. V. Gomes

This is a survey about the contruction of warped products between (semi-)Riemannian manifolds and metric (measure) spaces. The resulting spaces will be semi-Riemannian manifolds, metric (measure) spaces or Lorentzian metric and metric…

微分几何 · 数学 2025-03-17 Christian Ketterer

Given a Riemannian manifold $M,$ and an open interval $I\subset\mathbb{R},$ we characterize nontrivial totally umbilical hypersurfaces of the product $M\times I$ -- as well as of warped products $I\times_\omega M$ -- as those which are…

微分几何 · 数学 2021-01-05 Ronaldo F. de Lima , João Paulo dos Santos

We give a classification of many closed Riemannian manifolds M whose universal cover possesses a nontrivial amount of symmetry. More precisely, we consider closed Riemannian manifolds $M$ such that Isom$(\widetilde{M})$ has noncompact…

微分几何 · 数学 2014-05-12 Wouter van Limbeek

In the first part of this note we study compact Riemannian manifolds (M,g) whose Riemannian product with R is conformally Einstein. We then consider compact 6--dimensional almost Hermitian manifolds of type W_1+W_4 in the Gray--Hervella…

微分几何 · 数学 2019-01-08 Andrei Moroianu , Liviu Ornea

We discuss smooth metric measure spaces admitting two weighted Einstein representatives of the same weighted conformal class. First, we describe the local geometries of such manifolds in terms of certain Einstein and quasi-Einstein warped…

微分几何 · 数学 2025-04-11 Miguel Brozos-Vázquez , Eduardo García-Río , Diego Mojón-Álvarez

In this paper we study the warped product submanifolds of a Lorentzian paracosymplectic manifold and obtain some nonexistence results. We show that a warped product semi-invariant submanifold in the form {$M=M_{T}\times_{f}M_{\bot}$} of…

微分几何 · 数学 2016-08-14 Selcen Yüksel Perktaş , Erol Kılıç , Sadık Keleş

In this article, we study the problem of the existence and nonexistence of warping function associated with constant scalar curvature on pseudo-Riemannian Poisson warped product space under the assumption that fiber space has constant…

微分几何 · 数学 2022-02-08 B. Pal , P. Kumar

The goal of this article is to study the geometry of Bach-flat noncompact steady quasi-Einstein manifolds. We show that a Bach-flat noncompact steady quasi-Einstein manifold $(M^{n},\,g)$ with positive Ricci curvature such that its…

微分几何 · 数学 2016-12-15 M. Ranieri , E. Ribeiro

In this paper we consider connections between Ricci solitons and Einstein metrics on homogeneous spaces. We show that a semi-algebraic Ricci soliton admits an Einstein one-dimensional extension if the soliton derivation can be chosen to be…

微分几何 · 数学 2013-02-05 Chenxu He , Peter Petersen , William Wylie

Associated to any (pseudo)-Riemannian manifold $M$ of dimension $n$ is an $n+1$-dimensional noncommutative differential structure $(\Omega^1,\extd)$ on the manifold, with the extra dimension encoding the classical Laplacian as a…

量子代数 · 数学 2015-05-19 Shahn Majid

In this paper we study gradient Ricci-Harmonic soliton with structure of warped product manifold. We obtain some triviality results for the potential function, warping function and the harmonic map which reaches maximum or minimum. In order…

微分几何 · 数学 2019-07-01 Elismar Batista , Levi Adriano , Willian Tokura