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ON THE KHLER-RICCI SOLITONS WITH VANISHING BOCHNER-WEYL TENSOR 被引量:3
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作者 苏延辉 张坤 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1239-1244,共6页
In this article, we study the steady, shrinking, and expanding Kahler-Ricci solitons with vanishing Bochner-Weyl tensor and prove that, under this condition, the Ricci solitons must have constant holomorphic sectional... In this article, we study the steady, shrinking, and expanding Kahler-Ricci solitons with vanishing Bochner-Weyl tensor and prove that, under this condition, the Ricci solitons must have constant holomorphic sectional curvature. 展开更多
关键词 ricci flow Kahler ricci soliton Bochner-Weyl tensor
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ON SHRINKING GRADIENT RICCI SOLITONS WITH POSITIVE RICCI CURVATURE AND SMALL WEYL TENSOR 被引量:1
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作者 Zhuhong ZHANG Chih-Wei CHEN 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1235-1239,共5页
We show that closed shrinking gradient Ricci solitons with positive Ricci curvature and sufficiently pinched Weyl tensor are Einstein. When Weyl tensor vanishes, this has been proved before but our proof here is much ... We show that closed shrinking gradient Ricci solitons with positive Ricci curvature and sufficiently pinched Weyl tensor are Einstein. When Weyl tensor vanishes, this has been proved before but our proof here is much simpler. 展开更多
关键词 SHRINKING GRADIENT ricci SOLITONS POSITIVE ricci curvature pinched WEYL tensor
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New Way to Calculate Ricci Tensor and Ricci Scalar
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作者 Abed El Karim S. Abou Layla 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第3期850-867,共18页
In the theory of general relativity, the finding of the Einstein Field Equation happens in a complex mathematical operation, a process we don’t need any more. Through a new theory in vector analysis, we’ll see that ... In the theory of general relativity, the finding of the Einstein Field Equation happens in a complex mathematical operation, a process we don’t need any more. Through a new theory in vector analysis, we’ll see that we can calculate the components of the Ricci tensor, Ricci scalar, and Einstein Field Equation directly in an easy way without the need to use general relativity theory hypotheses, principles, and symbols. Formulating the general relativity theory through another theory will make it easier to understand this relativity theory and will help combining it with electromagnetic theory and quantum mechanics easily. 展开更多
关键词 General Relativity ricci tensor ricci SCALAR EINSTEIN Field Equation Stress-Energy tensor Robertson-Walker METRIC SCHWARZSCHILD METRIC
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四维完备梯度近Ricci孤立子的局部特征
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作者 路娟玲 刘建成 《吉林大学学报(理学版)》 CAS 北大核心 2023年第3期553-556,共4页
用几何分析的方法,并结合一些重要不等式,研究满足特定条件(与Weyl张量的反自对偶或自对偶部分相关)的四维完备梯度近Ricci孤立子的局部特征,证得该孤立子在局部上是具有三维常截面曲率纤维的卷积结构或具有三维Einstein纤维的卷积结构.
关键词 梯度近ricci孤立子 Weyl张量 卷积
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伪Ricci对称流形的几个调和性质
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作者 聂智 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2003年第6期846-849,共4页
利用Riemann曲率与Weyl共形曲率研究了特殊的Riemann流形———伪Ricci对称流形.同时得到了流形与子流形成为Ricci平坦空间的充要条件.
关键词 ricci对称流形 调和曲率张量 ricci平坦空间 拟Einstein流形 Riemann曲率 Weyl共形曲率
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具有两个不同Ricci主曲率的局部共形平坦Riemann流形
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作者 吴炳烨 《数学年刊(A辑)》 CSCD 北大核心 2011年第1期71-82,共12页
得到了具有常m阶Schouten曲率与两个不同Schouten主曲率(或者等价地,两个不同Ricci主曲率)的完备局部共形平坦Riemann流形的分类结果.作为应用,得到了若干Schouten张量的pinching性质.
关键词 局部共形平坦 ricci张量 SCHOUTEN张量 Schouten主曲率 m阶Schouten曲率
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RiCCi曲率平行的黎曼流形的刚性定理
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作者 廖蔡生 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第1期8-15,共8页
该文研究Ricci曲率平行的黎曼流形,将文[6]、[7]中Einstein流形的一些刚性定理推广到Ricci曲率平行的黎曼流形上。
关键词 ricci曲率 刚性定理 第一特征值 黎曼流形
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关于Ricci对称的黎曼流形的孤立性
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作者 蔡开仁 《绍兴文理学院学报(自然科学版)》 2003年第7期10-12,共3页
使用P.Li的Sobolev不等式和Lp估计方法,研究Ricci对称的黎曼流形的量子化现象.证明了对于紧致的具有正数量曲率的Ricci对称的黎曼流形M,存在一个常数A,当M的保圆曲率张量的La/2模小于A时,M为常曲率空间.
关键词 黎曼流形 孤立性 ricci对称 量子化 SOBOLEV不等式 Lp估计方法 保圆曲率张量 微分几何
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M-Eigenvalues of the Riemann Curvature Tensor of Conformally Flat Manifolds 被引量:1
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作者 Yun Miao Liqun Qi Yimin Wei 《Communications in Mathematical Research》 CSCD 2020年第3期336-353,共18页
We investigate the M-eigenvalues of the Riemann curvature tensor in the higher dimensional conformally flat manifold.The expressions of Meigenvalues and M-eigenvectors are presented in this paper.As a special case,M-e... We investigate the M-eigenvalues of the Riemann curvature tensor in the higher dimensional conformally flat manifold.The expressions of Meigenvalues and M-eigenvectors are presented in this paper.As a special case,M-eigenvalues of conformal flat Einstein manifold have also been discussed,and the conformal the invariance of M-eigentriple has been found.We also reveal the relationship between M-eigenvalue and sectional curvature of a Riemannian manifold.We prove that the M-eigenvalue can determine the Riemann curvature tensor uniquely.We also give an example to compute the Meigentriple of de Sitter spacetime which is well-known in general relativity. 展开更多
关键词 M-eigenvalue Riemann curvature tensor ricci tensor conformal invariant canonical form
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复双平面格拉斯曼中实超曲面的*-Ricci张量
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作者 廖春艳 陈小民 《南昌大学学报(理科版)》 CAS 北大核心 2019年第4期317-325,330,共10页
主要考虑在复双曲双面格拉斯曼SU2,m/S(U2U m),m≥2中的实超曲面的复曲率张量中引入*-Ricci张量。我们首先证明了SU2,m/S(U2U m)的Hopf超曲面上不存在*-Einstein度量。作为*-Einstein度量的一个推广,我们引入了*-Ricci孤立子,并证明了... 主要考虑在复双曲双面格拉斯曼SU2,m/S(U2U m),m≥2中的实超曲面的复曲率张量中引入*-Ricci张量。我们首先证明了SU2,m/S(U2U m)的Hopf超曲面上不存在*-Einstein度量。作为*-Einstein度量的一个推广,我们引入了*-Ricci孤立子,并证明了一个具有*-Ricci孤立子的实超曲面的位势场是Reeb矢量场,是SU2,m/S(U2U m)中全测地子流行SU2,m-1/S(U2U m-1)管状领域的一部分或者是一个无穷远处的中心是奇异的极限球面。最后,我们研究了一个具有伪反交换*-Ricci张量的Hopf超曲面。 展开更多
关键词 *-ricci张量 伪反交换*-ricci张量 *-Einstein Hopf超曲面 复双平面格拉斯曼 *-ricci孤立子
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Ricci孤立子的势函数
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作者 李金楠 高翔 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2022年第3期148-152,共5页
Bakry-Emery Ricci张量定义为Ric_(f)=Ric+Hessf。特殊地,当光滑实值函数f为常数时,Bakry-Emery Ricci张量为Ricci张量,方程Ric_(f)=ρg(ρ为常数)实际为梯度Ricci孤立子方程。本文应用Bakry-Emery Ricci张量与Riccati不等式来研究梯度R... Bakry-Emery Ricci张量定义为Ric_(f)=Ric+Hessf。特殊地,当光滑实值函数f为常数时,Bakry-Emery Ricci张量为Ricci张量,方程Ric_(f)=ρg(ρ为常数)实际为梯度Ricci孤立子方程。本文应用Bakry-Emery Ricci张量与Riccati不等式来研究梯度Ricci孤立子的势函数,分别给出扩张、稳定及收缩梯度Ricci孤立子势函数的下界估计。 展开更多
关键词 Bakry-Emery张量 ricci孤立子 势函数
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Finslerian Ricci Deformation and Conformal Metrics
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作者 Gilbert Nibaruta Serge Degla Léonard Todjihounde 《Journal of Applied Mathematics and Physics》 2018年第7期1522-1536,共15页
In this paper, a new Ricci flow is canonically introduced in Finsler Geometry and, under the variance of Finsler-Ehresmann form, conformal changes of Finsler metrics are studied. Some existence conditions of this Fins... In this paper, a new Ricci flow is canonically introduced in Finsler Geometry and, under the variance of Finsler-Ehresmann form, conformal changes of Finsler metrics are studied. Some existence conditions of this Finslerian Ricci flow on a compact manifold which preserves the conformal class of the initial metric are obtained as an application. 展开更多
关键词 Ehresmann CONNECTION ricci Flow Trace-Free ricci tensor CONFORMAL Change of Finsler-Ehresmann Form
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On Kirichenko Tensors of Nearly-Khlerian Manifolds
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作者 Mihail B.BANARU 《四川理工学院学报(自然科学版)》 CAS 2012年第4期1-5,共5页
A short description of structural and virtual Kirichenko tensors that form a complete system of first-order differential-geometrical invariants of an arbitrary almost Hermitian structure is given.A characterization of... A short description of structural and virtual Kirichenko tensors that form a complete system of first-order differential-geometrical invariants of an arbitrary almost Hermitian structure is given.A characterization of nearly-Khlerian structures in terms of Kirichenko tensors is also given. 展开更多
关键词 Kirichenko tensors ricci tensor nearly-Khlerian manifold almost Hermitian manifold six-dimensional submanifolds of Cayley algebra
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关于Bochner张量具有消灭条件的梯度收缩Kähler-Ricci孤立子
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作者 沈东 刘建成 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2022年第4期26-30,共5页
研究完备梯度收缩Kähler-Ricci孤立子,在Bochner张量的4阶散度等于零的条件下(即div^(4)(W)=▽_(k)▽_(j)▽_(i)▽_(l)W_(ijkl)=0),得到了其分类结果.
关键词 Kähler-ricci孤立子 Bochner张量 调和Bochner张量
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具有正Ricci曲率和小Weyl张量的梯度收缩近Ricci孤立子
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作者 刘建成 许雪阳 《西北师范大学学报(自然科学版)》 CAS 北大核心 2021年第6期1-6,共6页
研究具有正Ricci曲率和小Weyl张量的连通定向闭梯度收缩近Ricci孤立子,在孤立子函数的二阶协变导数满足适当的积分条件下,证明了该孤立子是Einstein流形.
关键词 梯度近ricci孤立子 EINSTEIN流形 ricci曲率 小Weyl张量
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完备非紧梯度扩张Ricci孤立子的刚性
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作者 陈佳蕊 刘建成 《吉林大学学报(理学版)》 CAS 北大核心 2019年第6期1403-1406,共4页
利用已有梯度Ricci孤立子的刚性定理,讨论完备非紧梯度扩张Ricci孤立子,在Ricci曲率非负、径向曲率为0及Weyl张量的四阶散度非负的条件下,得到了其刚性的结果.
关键词 梯度扩张ricci孤立子 刚性 径向曲率 Weyl张量
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Study of Complex TOUGMA’s Metric
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作者 Jean Luc Wendkouni Tougma 《Open Journal of Applied Sciences》 2023年第7期1005-1011,共7页
General relativity of Einstein’s theory and Quantum physics theory are excellent pillars that explain much modern physics. Understanding the relation between these theories is still a theoretical physics central open... General relativity of Einstein’s theory and Quantum physics theory are excellent pillars that explain much modern physics. Understanding the relation between these theories is still a theoretical physics central open question. Over last several decades, works in this direction have led to new physical ideas and mathematical tools broad range. In recent years TOUGMA’s equation is established and solved, one of its solutions such as a real solution is studied in our last article. In this paper, complex TOUGMA’s metric is studied, particularly the physics concepts that this metric implies such as light geodesic and metric’s impacts at r = 0. The first time, we studied the fact of r = 0 and its limits, secondly, we consider a zero length light geodesic is a geodesic and ended by studying it mathematically. These underlying principles study, those various phenomena in universe are interconnected logic leading to develop new technologies for example: news engines, telecommunication networks. This study’s applications are exceptionally wide such as Astrophysics, cosmology, Quantum gravity, Quantum Mechanics, Multiverse. Mostly this study lets us to know the quantum relativity universe behaviors. 展开更多
关键词 Complex Metric of TOUGMA Quantum Relativity ricci tensor
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Orbits of Material Bodies in Complex TOUGMA’s Metric
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作者 Jean Luc Wendkouni Tougma 《Open Journal of Applied Sciences》 2023年第8期1310-1318,共9页
Einstein’s General relativity theory and Quantum physics are the main pillars for explaining most modern physics. Obtaining these theories relation between them remains a theoretical physics main question. In the las... Einstein’s General relativity theory and Quantum physics are the main pillars for explaining most modern physics. Obtaining these theories relation between them remains a theoretical physics main question. In the last most decades, works are leading to new physical ideas and mathematical tools broad range. In recent years TOUGMA’s equation is established and solved, and one of these solutions, mostly a real solution is studied in our last article. In this work, complex TOUGMA’s metric is studied, such as the physics concepts implied by this metric, mainly material bodies geodesics orbits. We studied the fact material bodies’ orbits and their limits. This study of the underlying principles and various phenomena in universe are interconnected logic leading to new technologies development such as news engines and telecommunication networks. The applications of this study are exceptionally wide such as Astrophysics, cosmology, Quantum gravity, Quantum Mechanics and Multiverse. Mostly this study allows us to know the behaviors of matter in the quantum relativity universe. Universe. 展开更多
关键词 ricci tensor TOUGMA’s Complex Metric Quantum Relativity
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f-拉普拉斯算子正调和函数的梯度估计 被引量:1
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作者 黄广月 张晶 张丛丛 《河南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第5期10-12,共3页
设M是m维完备的黎曼流形.在∞-Bakry-Emery Ricci曲率和Ricci曲率都有下界的条件下,Chen得到了f-拉普拉斯算子正调和函数的一类梯度估计.仅在∞-Bakry-Emery Ricci曲率有下界的条件下,得到了与Chen类似的梯度估计.
关键词 梯度估计 f-拉普拉斯 ∞-bakry-emery ricci曲率
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一般伪黎曼空间中的极大类空子流形 被引量:2
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作者 杨慧章 龙瑶 李薇 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2013年第6期30-34,共5页
通过计算Ricci张量长度平方的拉普拉斯算子,得到了伪黎曼流形上的一个Simons型积分不等式,运用该不等式推广了已有的相关结果.
关键词 伪黎曼流形 拉普拉斯算子 ricci张量
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