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The Mathematical Foundations of General Relativity Revisited 被引量:2
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作者 Jean-Francois Pommaret 《Journal of Modern Physics》 2013年第8期223-239,共17页
The purpose of this paper is to present for the first time an elementary summary of a few recent results obtained through the application of the formal theory of partial differential equations and Lie pseudogroups in ... The purpose of this paper is to present for the first time an elementary summary of a few recent results obtained through the application of the formal theory of partial differential equations and Lie pseudogroups in order to revisit the mathematical foundations of general relativity. Other engineering examples (control theory, elasticity theory, electromagnetism) will also be considered in order to illustrate the three fundamental results that we shall provide successively. 1) VESSIOT VERSUS CARTAN: The quadratic terms appearing in the “Riemann tensor” according to the “Vessiot structure equations” must not be identified with the quadratic terms appearing in the well known “Cartan structure equations” for Lie groups. In particular, “curvature + torsion” (Cartan) must not be considered as a generalization of “curvature alone” (Vessiot). 2) JANET VERSUS SPENCER: The “Ricci tensor” only depends on the nonlinear transformations (called “elations” by Cartan in 1922) that describe the “difference” existing between the Weyl group (10 parameters of the Poincaré subgroup + 1 dilatation) and the conformal group of space-time (15 parameters). It can be defined without using the indices leading to the standard contraction or trace of the Riemann tensor. Meanwhile, we shall obtain the number of components of the Riemann and Weyl tensors without any combinatoric argument on the exchange of indices. Accordingly and contrary to the “Janet sequence”, the “Spencer sequence” for the conformal Killing system and its formal adjoint fully describe the Cosserat equations, Maxwell equations and Weyl equations but General Relativity is not coherent with this result. 3) ALGEBRA VERSUS GEOMETRY: Using the powerful methods of “Algebraic Analysis”, that is a mixture of homological agebra and differential geometry, we shall prove that, contrary to other equations of physics (Cauchy equations, Cosserat equations, Maxwell equations), the Einstein equations cannot be “parametrized”, that is the g 展开更多
关键词 General Relativity Riemann tensor Weyl tensor ricci tensor Einstein Equations LIE Groups LIE Pseudogroups DIFFERENTIAL SEQUENCE SPENCER Operator JANET SEQUENCE SPENCER SEQUENCE DIFFERENTIAL Module Homological Algebra Extension Modules Split Exact SEQUENCE
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一个新的Simons型不等式 被引量:3
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作者 陈六新 郭震 李同柱 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2003年第4期533-535,共3页
通过计算Ricci张量长度平方的Laplace,得到一个新的Simons型不等式;运用该不等式作拼挤,在一个比法丛平坦弱的条件下得到了一个Pinching常数.推广了前人所作的关于法丛平坦的结果,也得到了与Ricci曲率平行有关的相应结果.
关键词 Simons型不等式 ricci张量 法丛平坦 PINCHING常数 拼挤 第二基本形式长度 微分几何 黎曼流形
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New Homogeneous Einstein Metrics on SO(7)/T 被引量:2
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作者 Yu WANG Tianzeng LI Guosong ZHAO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2018年第1期97-110,共14页
The authors compute non-zero structure constants of the full flag manifold M = SO(7)/T with nine isotropy summands,then construct the Einstein equations.With the help of computer they get all the forty-eight positive ... The authors compute non-zero structure constants of the full flag manifold M = SO(7)/T with nine isotropy summands,then construct the Einstein equations.With the help of computer they get all the forty-eight positive solutions(up to a scale) for SO(7)/T,up to isometry there are only five G-invariant Einstein metrics,of which one is Khler Einstein metric and four are non-Khler Einstein metrics. 展开更多
关键词 Generalized flag manifold Einstein metric ricci tensor Isotropy representation ISOMETRY
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Why Gravitational Waves Cannot Exist
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作者 J.-F. Pommaret 《Journal of Modern Physics》 2017年第13期2122-2158,共37页
The purpose of this short but difficult paper is to revisit the mathematical foundations of both General Relativity (GR) and Gauge Theory (GT) in the light of a modern approach to nonlinear systems of ordinary or part... The purpose of this short but difficult paper is to revisit the mathematical foundations of both General Relativity (GR) and Gauge Theory (GT) in the light of a modern approach to nonlinear systems of ordinary or partial differential equations, using new methods from Differential Geometry (D.C. Spencer, 1970), Differential Algebra (J.F. Ritt, 1950 and E. Kolchin, 1973) and Algebraic Analysis (M. Kashiwara, 1970). The main idea is to identify the differential indeterminates of Ritt and Kolchin with the jet coordinates of Spencer, in order to study Differential Duality by using only linear differential operators with coefficients in a differential field K. In particular, the linearized second order Einstein operator and the formal adjoint of the Ricci operator are both parametrizing the 4 first order Cauchy stress equations but cannot themselves be parametrized. In the framework of Homological Algebra, this result is not coherent with the vanishing of a certain second extension module and leads to question the proper origin and existence of gravitational waves. As a byproduct, we also prove that gravitation and electromagnetism only depend on the second order jets (called elations by E. Cartan in 1922) of the system of conformal Killing equations because any 1-form with value in the bundle of elations can be decomposed uniquely into the direct sum (R, F) where R is a section of the Ricci bundle of symmetric covariant 2-tensors and the EM field F is a section of the vector bundle of skew-symmetric 2-tensors. No one of these purely mathematical results could have been obtained by any classical approach. Up to the knowledge of the author, it is also the first time that differential algebra in a modern setting is applied to study the specific algebraic feature of most equations to be found in mathematical physics, particularly in GR. 展开更多
关键词 General Relativity Riemann tensor Weyl tensor ricci tensor Einstein Equations Elastic WAVES Gravitational WAVES LIE Groups LIE Pseudogroups Differential Galois Theory SPENCER Operator Janet SEQUENCE SPENCER SEQUENCE Differential MODULES Algebraic Analysis Homological Algebra Extension MODULES Split Exact SEQUENCE
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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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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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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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SU(4)/T上不变爱因斯坦度量(英文) 被引量:2
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作者 王瑜 李天增 《数学进展》 CSCD 北大核心 2014年第5期781-788,共8页
本文计算了迷向表示和为6的满旗流形M=SU(4)/T上非零结构常数,然后给出了爱因斯坦方程.众所周知,满旗流形M=SU(4)/T在差常数倍的情况下有29个SU(4)-不变的爱因斯坦度量.利用计算机程序,得到了满旗流形SU(4)/T的爱因斯坦方程组的29个正解... 本文计算了迷向表示和为6的满旗流形M=SU(4)/T上非零结构常数,然后给出了爱因斯坦方程.众所周知,满旗流形M=SU(4)/T在差常数倍的情况下有29个SU(4)-不变的爱因斯坦度量.利用计算机程序,得到了满旗流形SU(4)/T的爱因斯坦方程组的29个正解(差常数倍的情况下),其中在等距的情况下有1个凯莱爱因斯坦度量,3个非凯莱爱因斯坦度量. 展开更多
关键词 广义旗流形 爱因斯坦度量 ricci张量 迷向表示
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Examination of Schrodinger Equation in Pre-Planckian Space-Time Early Universe 被引量:1
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第1期21-28,共8页
We look at the Vuilli (1999) write up of a generalized Schrodinger equation with its Ricci scalar inclusion, in curved space-time. This has a simplified version in Pre-Planckian regime, which leads to comparing a resu... We look at the Vuilli (1999) write up of a generalized Schrodinger equation with its Ricci scalar inclusion, in curved space-time. This has a simplified version in Pre-Planckian regime, which leads to comparing a resultant admissible wave function with Bohmian reformulations of quantum physics. As was done earlier, we compare this result with a formulation of a modified “Poisson” equation from Poissons and Will from 2014, and then use inflaton physics. The resulting inflaton is then compared to the wave functional in the first part of this document. 展开更多
关键词 ricci tensor SCHRODINGER EQUATION Modified POISSON EQUATION Massive Gravity INFLATON Physics
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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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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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H-射影循环Kaehler流形 被引量:1
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作者 李中林 《杭州大学学报(自然科学版)》 CSCD 1994年第1期16-19,共4页
本文研究H-射影循环Kaehler流形的性质,导出了该流形曲由张量的代数结构,从而深化了这类流形的已有结果.
关键词 KAEHLER流形 曲率张量 H射影循环
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Commuting Structure Jacobi Operator for Real Hypersurfaces in Complex Space Forms
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作者 U-Hang Ki Hiroyuki Kurihara 《Advances in Pure Mathematics》 2013年第2期264-276,共13页
Let M be a real hypersurface of a complex space form with almost contact metric structure (φ,ξ,η,g). In this paper, we prove that if the structure Jacobi operator Rξ=(·,ξ) ξ is φ▽ξξ-parallel and Rξ com... Let M be a real hypersurface of a complex space form with almost contact metric structure (φ,ξ,η,g). In this paper, we prove that if the structure Jacobi operator Rξ=(·,ξ) ξ is φ▽ξξ-parallel and Rξ commute with the shape operator, then M is a Hopf hypersurface. Further, if Rξ is φ▽ξξ-parallel and Rξ commute with the Ricci tensor, then M is also a Hopf hypersurface provided that TrRξ is constant. 展开更多
关键词 Complex Space Form Hopf HYPERSURFACE STRUCTURE JACOBI OPERATOR Shape OPERATOR ricci tensor
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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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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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广义相对论中不同符号约定的比较与转换 被引量:1
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作者 李雪松 冯开喜 张宏浩 《大学物理》 北大核心 2010年第6期24-26,29,共4页
分析比较了在广义相对论中由度规、里奇张量,以及宇宙学常数的定义不同而导致的不同的符合约定,并给出了不同符合约定之间的转换关系.
关键词 度规张量 里奇张量 宇宙学常数
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何时任意常半径的切球丛是Einstein的(英文)
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作者 陈冬梅 胡自胜 《数学研究》 CSCD 2009年第3期244-250,共7页
研究具有任意常半径r的切球丛,得到该切球丛是Einstein的一个充分必要条件。
关键词 切球丛 超曲面 EINSTEIN流形 ricci张量
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广义旗流形SU(5)/U^3(1)×SU(2)齐性变爱因斯坦度量(英文)
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作者 王瑜 贾红艳 李天增 《河南大学学报(自然科学版)》 CAS 2015年第1期15-20,共6页
利用李代数的知识可以计算旗流形M=SU(5)/U3(1)×SU(2)上非零的结构常数ck ij,然后把非零的ck ij代入Ricc张量的分量γ1,…,γ6.旗流形M上G-不变的黎曼度量g是爱因斯坦度量当且仅当存在正常数e,使得γ1=γ2=γ3=γ4=γ5=γ6=e.利用... 利用李代数的知识可以计算旗流形M=SU(5)/U3(1)×SU(2)上非零的结构常数ck ij,然后把非零的ck ij代入Ricc张量的分量γ1,…,γ6.旗流形M上G-不变的黎曼度量g是爱因斯坦度量当且仅当存在正常数e,使得γ1=γ2=γ3=γ4=γ5=γ6=e.利用计算Grbner基的方法得到爱因斯坦方程组有27个正的实数解,即广义旗流形M=SU(5)/U3(1)×SU(2)上有27个不变的爱因斯坦度量(在差常数倍的情况下),其中12个是凯莱爱因斯坦度量,15个是非凯莱爱因斯坦度量. 展开更多
关键词 广义旗流形 爱因斯坦度量 ricci张量 迷向表示
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Ricci张量对称函数的预定问题
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作者 贺妍 张维维 《数学学报(中文版)》 CSCD 北大核心 2021年第1期41-46,共6页
本文考虑Ricci张量的对称函数σ2 (Ricg)的预定问题.假设(M,g)是闭的Einstein流形,我们得到了只要流形(M,g)不具有σ2 (Ric)奇性,则对于变号的函数f∈C^∞(M),存在度量g^*,使得σ2 (Ricg^*)=f.然后,作为推论,得到了具有负数量曲率的闭Ei... 本文考虑Ricci张量的对称函数σ2 (Ricg)的预定问题.假设(M,g)是闭的Einstein流形,我们得到了只要流形(M,g)不具有σ2 (Ric)奇性,则对于变号的函数f∈C^∞(M),存在度量g^*,使得σ2 (Ricg^*)=f.然后,作为推论,得到了具有负数量曲率的闭Einstein流形上的预定曲率的结果. 展开更多
关键词 对称函数 ricci张量 预定曲率问题
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广义旗流形上不变爱因斯坦度量与结构等测地向量(英文)
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作者 王瑜 李天增 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第4期674-680,共7页
满旗流形SU(n)/T上至少有n!/2+n+1个不变的爱因斯坦度量,其中n!/2个是Khler爱因斯坦度量.但当n5时关于满旗流形SU(n)/T上不变爱因斯坦度量至今没有更多的结果.本文得到满旗流形SU(5)/T上在差常数倍的情况下有386个不变的爱因斯坦度... 满旗流形SU(n)/T上至少有n!/2+n+1个不变的爱因斯坦度量,其中n!/2个是Khler爱因斯坦度量.但当n5时关于满旗流形SU(n)/T上不变爱因斯坦度量至今没有更多的结果.本文得到满旗流形SU(5)/T上在差常数倍的情况下有386个不变的爱因斯坦度量.这是用度量对满旗流形SU(n)/T(n5)进行分类的最新结果.然后作者考虑了第二Betti数为1的广义旗流形上结构等测地向量. 展开更多
关键词 广义旗流形 爱因斯坦度量 结构等测地向量 ricci张量 迷向表示
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