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Embedding the Einstein Tensor in the Klein-Gordon Equation Using Geometric Algebra Cl_(3,0)
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作者 Jesús Sánchez 《Journal of Applied Mathematics and Physics》 2025年第10期3515-3572,共58页
In this paper,we will use Geometric Algebra to be able to embed the Klein-Gordon equation for a particle in a non-Euclidean field(gravitational field).This way,we will obtain an expression similar to the Dirac equatio... In this paper,we will use Geometric Algebra to be able to embed the Klein-Gordon equation for a particle in a non-Euclidean field(gravitational field).This way,we will obtain an expression similar to the Dirac equation,but with a slight change in one of the terms.This variation is produced and depends on the curvature of the space where the particle lies in(the Ricci scalar).In a similar manner,we will find variations in the equation for the energy of a particle and in the Einstein gravitational equation that will depend again on the value of the Ricci scalar(the curvature of the space where the particle lies in).An important outcome will be an equation that limits the value of the Ricci scalar depending on the value of the mass that provokes it(the value of the mass,not the mass density),highly reducing the possibilities of arriving at singularities.In fact,the value of this R has been found to be equal to the cosmological constant(both in the order of 1E-52),making it a perfect candidate for the dark energy.Also,the magnetic-like effects of gravitation coming from the equations are sufficient to explain the rotation of the galaxies(NGC 1560,NGC 3198 and NGC 3115)without the need for dark matter. 展开更多
关键词 Geometric Algebra einstein tensor Klein-Gordon Equation Bra-Ket Product Non-Euclidean Metric
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Generalized Einstein Tensor for a Weyl Manifold and Its Applications
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作者 Abdlkadir ZDEGER 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2013年第2期373-382,共10页
It is well known that the Einstein tensor G for a Riemannian manifold defined by Gα^β = 1/2α^β ,Rα^β=g^α^β γ where Rγα and R are respectively the Ricci tensor and the scalar curvature of the manifold, p... It is well known that the Einstein tensor G for a Riemannian manifold defined by Gα^β = 1/2α^β ,Rα^β=g^α^β γ where Rγα and R are respectively the Ricci tensor and the scalar curvature of the manifold, plays an important part in Einstein s theory of gravitation as well as in proving some theorems in Riemannian geometry. In this work, we first obtain the generalized Einstein tensor for a Weyl manifold. Then, after studying some properties of generalized Einstein tensor, we prove that the conformal invariance of the generalized Einstein tensor implies the conformal invariance of the curvature tensor of the Weyl manifold and conversely. Moreover, we show that such Weyl manifolds admit a one-parameter family of hypersurfaces the orthogonal trajectories of which are geodesics. Finally, a necessary and sufficient condition in order that the generalized circles of a Weyl manifold be preserved by a conformal mapping is stated in terms of generalized Einstein tensors at corresponding points. 展开更多
关键词 Weyl manifold einstein-Weyl manifold einstein tensor generalized einstein tensor generalized circle
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Einstein’s Pseudo-Tensor in <i>n</i>Spatial Dimensions for Static Systems with Spherical Symmetry
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作者 Frank R. Tangherlini 《Journal of Modern Physics》 2013年第9期1200-1204,共5页
It was noted earlier that the general relativity field equations for static systems with spherical symmetry can be put into a linear form when the source energy density equals radial stress. These linear equations lea... It was noted earlier that the general relativity field equations for static systems with spherical symmetry can be put into a linear form when the source energy density equals radial stress. These linear equations lead to a delta function energymomentum tensor for a point mass source for the Schwarzschild field that has vanishing self-stress, and whose integral therefore transforms properly under a Lorentz transformation, as though the particle is in the flat space-time of special relativity (SR). These findings were later extended to n spatial dimensions. Consistent with this SR-like result for the source tensor, Nordstrom and independently, Schrodinger, found for three spatial dimensions that the Einstein gravitational energy-momentum pseudo-tensor vanished in proper quasi-rectangular coordinates. The present work shows that this vanishing holds for the pseudo-tensor when extended to n spatial dimensions. Two additional consequences of this work are: 1) the dependency of the Einstein gravitational coupling constant κ on spatial dimensionality employed earlier is further justified;2) the Tolman expression for the mass of a static, isolated system is generalized to take into account the dimensionality of space for n ≥ 3. 展开更多
关键词 Field EQUATIONS Point Particle Dimensionality of Space einstein’s Pseudo-tensor
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关于球空间中Moebius形式消失的Einstein超曲面
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作者 杨慧章 穆凤 《红河学院学报》 2009年第2期21-23,26,共4页
x:Mn→Sn+1为(n+1)维单位球空间Sn+1中的无脐点超曲面,本文给出并证明了单位球空间中Moebius形式消失的Einstein超曲面的分类定理.
关键词 einstein超曲面 BLASCHKE张量 MOEBIUS形式
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关于Kaehler-Einstein流形上Rastogi联络的一点注记
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作者 宋晓新 王红菲 《大学数学》 2010年第3期60-63,共4页
研究Kaehler-Einstein流形M上Rastogi;联络的拟共形曲率张量场W-,证明了若-W是平行的,则M是拟共形对称的.也得到关于M共圆对称的对应条件和结果,推广了Rastogi,贾兴琴等的工作.
关键词 Kaehler-einstein流形 1/4对称度量联络 拟共形曲率张量场
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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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Tensors of Rank Two in Tensor Flight Dynamics
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作者 Peter H. Zipfel 《Advances in Aerospace Science and Technology》 2018年第2期11-19,共9页
Tensor flight dynamics solves flight dynamics problems using Cartesian tensors, which are invariant under coordinate transformations, rather than Gibbs’ vectors, which change under time-varying transformations. Three... Tensor flight dynamics solves flight dynamics problems using Cartesian tensors, which are invariant under coordinate transformations, rather than Gibbs’ vectors, which change under time-varying transformations. Three tensors of rank two play a prominent role and are the subject of this paper: moment of inertia, rotation, and angular velocity tensor. A new theorem is proven governing the shift of reference frames, which is used to derive the angular velocity tensor from the rotation tensor. As applications, the general strap-down INS equations are derived, and the effect of the time-rate-of-change of the moment of inertia tensor on missile dynamics is investigated. 展开更多
关键词 tensor Flight DYNAMICS COVARIANCE Principle einstein Rotation tensor Angular Velocity tensor Moment of INERTIA tensor Rotational Time Derivative Euler Transformation INS Missile DYNAMICS
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轴对称理想流体内部度规的研究——EinStein场方程的一组严格解析解
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作者 周启煌 吕君丽 《晓庄学院自然科学学报》 CAS 1992年第2期131-133,共3页
本文讨论了静态轴对称理想流体的内部度规,其能量密度消除了中心发散性,并得到一套精确解析解.文章所讨论的流体具有内压强,因而此解在理论上较其它解普遍.
关键词 理想流体 内部度规
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Second Approximation of the Generalized Planetary Equation Based upon Golden Metric Tensors
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作者 Nura Yakubu Hayatu Abbba Ibrahim +1 位作者 Musa Hashimu Umar Bappah Alkali 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期7-26,共20页
In this paper, we consider the Post Einstein Planetary equation of motion. We succeeded in offering a solution using second approximation method, in which we obtained eight exact mathematical solutions that rebel amaz... In this paper, we consider the Post Einstein Planetary equation of motion. We succeeded in offering a solution using second approximation method, in which we obtained eight exact mathematical solutions that rebel amazing theoretical results. To the order of C<sup>-2</sup>, two of these exact solutions are reduced to the approximate solutions from the method of successive approximations. 展开更多
关键词 Golden Matric tensors einstein’s Planetary Equation
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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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VMHD流体的Einstein场方程精确解
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作者 贺锋 《湘潭师范学院学报(社会科学版)》 1990年第3期37-42,共6页
本论文给出其几何部分与具有k=0,±1的FRW尘埃模型的几何部分相同的粘滞电磁流体动力学流体Einstein场方程精确解,这些解具有径向流动流体,所有必需的能量条件和热力学条件都得以满足,只要模型是膨胀的,所有物理量在时空各处都有物... 本论文给出其几何部分与具有k=0,±1的FRW尘埃模型的几何部分相同的粘滞电磁流体动力学流体Einstein场方程精确解,这些解具有径向流动流体,所有必需的能量条件和热力学条件都得以满足,只要模型是膨胀的,所有物理量在时空各处都有物理意义. 与标准FRW模型相比,本论文的模型有以下优点:其物质场更加具有物理现实性,更加细致地考虑确定宇宙物质内容膨胀最终行为的临界密度问题,等等. 展开更多
关键词 张量 爱因斯坦张量 宇宙学模型
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Representation of Physical Fields as Einstein Manifold
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作者 Vu B. Ho 《Journal of Applied Mathematics and Physics》 2023年第3期599-607,共9页
In this work we investigate the possibility to represent physical fields as Einstein manifold. Based on the Einstein field equations in general relativity, we establish a general formulation for determining the metric... In this work we investigate the possibility to represent physical fields as Einstein manifold. Based on the Einstein field equations in general relativity, we establish a general formulation for determining the metric tensor of the Einstein manifold that represents a physical field in terms of the energy-momentum tensor that characterises the physical field. As illustrations, we first apply the general formulation to represent the perfect fluid as Einstein manifold. However, from the established relation between the metric tensor and the energy-momentum tensor, we show that if the trace of the energy-momentum tensor associated with a physical field is equal to zero then the corresponding physical field cannot be represented as an Einstein manifold. This situation applies to the electromagnetic field since the trace of the energy-momentum of the electromagnetic field vanishes. Nevertheless, we show that a system that consists of the electromagnetic field and non-interacting charged particles can be represented as an Einstein manifold since the trace of the corresponding energy-momentum of the system no longer vanishes. As a further investigation, we show that it is also possible to represent physical fields as maximally symmetric spaces of constant scalar curvature. 展开更多
关键词 General Relativity einstein Manifold Energy-Momentum tensor Electromagnetic Field Perfect Fluid Maximally Symmetric Spaces
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Einstein’s General Relativity and Pure Gravity in a Cosserat and De Sitter-Witten Spacetime Setting as the Explanation of Dark Energy and Cosmic Accelerated Expansion
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2014年第2期332-339,共8页
Ordinary energy and dark energy density are determined using a Cosserat-Cartan and killing-Yano reinterpretation of Einstein’s special and general relativity. Thus starting from a maximally symmetric space with 528 k... Ordinary energy and dark energy density are determined using a Cosserat-Cartan and killing-Yano reinterpretation of Einstein’s special and general relativity. Thus starting from a maximally symmetric space with 528 killing vector fields corresponding to Witten’s five Branes model in eleven dimensional M-theory we reason that 504 of the 528 are essentially the components of the relevant killing-Yano tensor. In turn this tensor is related to hidden symmetries and torsional coupled stresses of the Cosserat micro-polar space as well as the Einstein-Cartan connection. Proceeding in this way the dark energy density is found to be that of Einstein’s maximal energy mc2 where m is the mass and c is the speed of light multiplied with a Lorentz factor equal to the ratio of the 504 killing-Yano tensor and the 528 states maximally symmetric space. Thus we have E (dark) = mc2 (504/528) = mc2 (21/22) which is about 95.5% of the total maximal energy density in astounding agreement with COBE, WMAP and Planck cosmological measurements as well as the type 1a supernova analysis. Finally theory and results are validated via a related theory based on the degrees of freedom of pure gravity, the theory of nonlocal elasticity as well as ‘t Hooft-Veltman renormalization method. 展开更多
关键词 General RELATIVITY COSSERAT Micro-Polar Space Dark Energy Teleparellelism Witten’s M-THEORY De Sitter SPACETIME Killing-Yano tensor einstein-Cartan RELATIVITY PURE GRAVITY Kaluza-Klein Theory Nonlocal Elasticity 't Hooft-Veltman Renormalization
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Airy, Beltrami, Maxwell, Einstein and Lanczos Potentials Revisited 被引量:1
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作者 J.-F. Pommaret 《Journal of Modern Physics》 2016年第7期699-728,共30页
The purpose of this paper is to revisit the well known potentials, also called stress functions, needed in order to study the parametrizations of the stress equations, respectively provided by G.B. Airy (1863) for 2-d... The purpose of this paper is to revisit the well known potentials, also called stress functions, needed in order to study the parametrizations of the stress equations, respectively provided by G.B. Airy (1863) for 2-dimensional elasticity, then by E. Beltrami (1892), J.C. Maxwell (1870) for 3-dimensional elasticity, finally by A. Einstein (1915) for 4-dimensional elasticity, both with a variational procedure introduced by C. Lanczos (1949, 1962) in order to relate potentials to Lagrange multipliers. Using the methods of Algebraic Analysis, namely mixing differential geometry with homological algebra and combining the double duality test involved with the Spencer cohomology, we shall be able to extend these results to an arbitrary situation with an arbitrary dimension n. We shall also explain why double duality is perfectly adapted to variational calculus with differential constraints as a way to eliminate the corresponding Lagrange multipliers. For example, the canonical parametrization of the stress equations is just described by the formal adjoint of the  components of the linearized Riemann tensor considered as a linear second order differential operator but the minimum number of potentials needed is equal to for any minimal parametrization, the Einstein parametrization being “in between” with potentials. We provide all the above results without even using indices for writing down explicit formulas in the way it is done in any textbook today, but it could be strictly impossible to obtain them without using the above methods. We also revisit the possibility (Maxwell equations of electromagnetism) or the impossibility (Einstein equations of gravitation) to obtain canonical or minimal parametrizations for various equations of physics. It is nevertheless important to notice that, when n and the algorithms presented are known, most of the calculations can be achieved by using computers for the corresponding symbolic computations. Finally, though the paper is mathematically oriented as it aims providing new insights towards the mathematical foundations of general relativity, it is written in a rather self-contained way. 展开更多
关键词 Stress Equations Stress Functions Elasticity Theory Lagrange Multipliers Formal Adjoint Control Theory General Relativity einstein Equations Lanczos Potentials Algebraic Analysis Riemann tensor Weyl tensor
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On Quasi-Einstein Field Equation
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作者 赵培标 杨孝平 《Northeastern Mathematical Journal》 CSCD 2005年第4期411-420,共10页
In this paper some properties of a symmetric tensor field T(X,Y) = g(A(X), Y) on a Riemannian manifold (M, g) without boundary which satisfies the S quasi-Einstein equation Rij-S/2gij=Tij+bξiξj are given. ... In this paper some properties of a symmetric tensor field T(X,Y) = g(A(X), Y) on a Riemannian manifold (M, g) without boundary which satisfies the S quasi-Einstein equation Rij-S/2gij=Tij+bξiξj are given. The necessary and sufficient conditions for this tensor to satisfy the quasi-Einstein equation are also obtained. 展开更多
关键词 einstein field equation quasi-einstein field equation Minkowski space Parallel field gravitational field “Ricci” symmetric tensor Lagrange equation
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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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偶数阶张量core逆的性质和应用 被引量:1
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作者 王宏兴 张晓燕 《数学物理学报(A辑)》 CSCD 北大核心 2021年第1期1-14,共14页
张量广义逆是张量理论研究的重要内容之一,在近年张量广义逆研究的基础上.该文给出在爱因斯坦积下张量core逆的性质、张量偏序和张量方程A*X=B在条件χ∈R(A)下的最小二乘解等.
关键词 core逆 爱因斯坦积 偏序 张量方程
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静态球对称星体结构方程的不同推导与比较
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作者 文德华 陈伟 +3 位作者 王先菊 艾保全 刘国涛 刘良钢 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2003年第2期15-17,共3页
给出了两种不同的静态球对称星体结构方程的推导过程,并对其进行了比较,指出方法二是一种更简 单、直接的推导方法。评述了该结构方程的适用范围。
关键词 静态球对称星体结构方程 推导过程 能量-动量张量 einstein场方程 广义相对论
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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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满旗流形SO(8)/T上不变爱因斯坦度量(英文)
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作者 王瑜 李天增 《数学杂志》 CSCD 北大核心 2015年第6期1319-1328,共10页
本文研究了迷向表示分为12个不可约子空间的满旗流形SO(8)/T上不变爱因斯坦度量的问题.利用计算机计算满旗流形SO(8)/T爱因斯坦方程组的方法,得到了满旗流形SO(8)/T上有160个不变爱因斯坦度量(up to a scale)的结果,在等距情况下考虑这... 本文研究了迷向表示分为12个不可约子空间的满旗流形SO(8)/T上不变爱因斯坦度量的问题.利用计算机计算满旗流形SO(8)/T爱因斯坦方程组的方法,得到了满旗流形SO(8)/T上有160个不变爱因斯坦度量(up to a scale)的结果,在等距情况下考虑这160个不变爱因斯坦度量,其中1个是凯莱爱因斯坦度量,4个是非凯莱爱因斯坦度量.推广了只对迷向表示分为小于等于6个不可约子空间的满旗流形上不变爱因斯坦度量的研究. 展开更多
关键词 满旗流形 爱因斯坦度量 RICCI张量 迷向表示
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