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Energy,momentum and angular momentum in the dyadosphere of a charged spacetime in teleparallel equivalent of general relativity
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作者 Gamal G.L.Nashed 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期85-91,共7页
We apply the energy momentum and angular momentum tensor to a tetrad field, with two unknown functions of radial coordinate, in the framework of a teleparallel equivalent of general relativity (TEGR). The definition... We apply the energy momentum and angular momentum tensor to a tetrad field, with two unknown functions of radial coordinate, in the framework of a teleparallel equivalent of general relativity (TEGR). The definition of the gravitational energy is used to investigate the energy within the external event horizon of the dyadosphere region for the Reissner-NordstrSm black hole. We also calculate the spatial momentum and angular momentum. 展开更多
关键词 Teleparallel equivalent of general relativity energy-momentum tensor angular momen- tum tensor angular momentum
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Relativistic Mechanics in Positive and Negative Subspace-Time according to the Inverse Relativity Model
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作者 Michael Girgis 《Journal of Applied Mathematics and Physics》 2024年第11期3784-3815,共32页
In the second paper on the inverse relativity model, we explained in the first paper [1] that analyzing the four-dimensional displacement vector on space-time according to a certain approach leads to the splitting of ... In the second paper on the inverse relativity model, we explained in the first paper [1] that analyzing the four-dimensional displacement vector on space-time according to a certain approach leads to the splitting of space-time into positive and negative subspace-time. Here, in the second paper, we continue to analyze each of the four-dimensional vectors of velocity, acceleration, momentum, and forces on the total space-time fabric. According to the approach followed in the first paper. As a result, in the special case, we obtain new transformations for each of the velocity, acceleration, momentum, energy, and forces specific to each subspace-time, which are subject to the positive and negative modified Lorentz transformations described in the first paper. According to these transformations, momentum remains a conserved quantity in the positive subspace and increases in the negative subspace, while the relativistic total energy decreases in the positive subspace and increases in the negative subspace. In the general case, we also have new types of energy-momentum tensor, one for positive subspace-time and the other for negative subspace-time, where the energy density decreases in positive subspace-time and increases in negative subspace-time, and we also obtain new gravitational field equations for each subspace-time. 展开更多
关键词 4D Velocity Vector Analysis positive Subspace Negative Subspace Negative Relativistic Mechanics positive tensor of energy and momentum Inverse Theory of Relativity
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A Locally Conservative Energy-Momentum Tensor in the General Relativity Based on a Cosmological Model without Singularity 被引量:1
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作者 Shihao Chen 《Journal of Modern Physics》 2016年第3期277-280,共4页
According to the conventional theory it is difficult to define the energy-momentum tensor which is locally conservative. The energy-momentum tensor of the gravitational field is defined. Based on a cosmological model ... According to the conventional theory it is difficult to define the energy-momentum tensor which is locally conservative. The energy-momentum tensor of the gravitational field is defined. Based on a cosmological model without singularity, the total energy-momentum tensor is defined which is locally conservative in the general relativity. The tensor of the gravitational mass is different from the energy-momentum tensor, and it satisfies the gravitational field equation and its covariant derivative is zero. 展开更多
关键词 energy-momentum tensor of Gravitational Field Locally Conservative energy-momentum tensor in General Relativity tensor of the Gravitational Mass Quasi-Local energy-momentum tensor
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Brane world black holes in teleparallel theory equivalent to general relativity and their Killing vectors,energy,momentum and angular momentum
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作者 Gamal G.L.Nashed 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期77-91,共15页
The energy--momentum tensor, which is coordinate-independent, is used to calculate energy, momentum and angular momentum of two different tetrad fields. Although, the two tetrad fields reproduce the same space--time t... The energy--momentum tensor, which is coordinate-independent, is used to calculate energy, momentum and angular momentum of two different tetrad fields. Although, the two tetrad fields reproduce the same space--time their energies are different. Therefore, a regularized expression of the gravitational energy--momentum tensor of the teleparallel equivalent of general relativity (TEGR), is used to make the energies of the two tetrad fields equal. The definition of the gravitational energy--momentum is used to investigate the energy within the external event horizon. The components of angular momentum associated with these space--times are calculated. In spite of using a static space--time, we get a non-zero component of angular momentum! Therefore, we derive the Killing vectors associated with these space--times using the definition of the Lie derivative of a second rank tensor in the framework of the TEGR to make the picture more clear. 展开更多
关键词 teleparallel equivalent of general relativity brane world black holes gravitational energy--momentum tensor regularized expression of the gravitational energy--momentum
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Fourth Rank Energy-Momentum Tensor
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作者 Vu B. Ho 《Journal of Applied Mathematics and Physics》 2022年第12期3684-3692,共9页
In this work, we introduce the new concept of fourth rank energy-momentum tensor. We first show that a fourth rank electromagnetic energy-momentum tensor can be constructed from the second rank electromagnetic energy-... In this work, we introduce the new concept of fourth rank energy-momentum tensor. We first show that a fourth rank electromagnetic energy-momentum tensor can be constructed from the second rank electromagnetic energy-momentum tensor. We then generalise to construct a fourth rank stress energy-momentum tensor and apply it to Dirac field of quantum particles. Furthermore, since the established fourth rank energy-momentum tensors have mathematical properties of the Riemann curvature tensor, thus it is reasonable to suggest that quantum fields should also possess geometric structures of a Riemannian manifold. 展开更多
关键词 Fourth Rank energy-momentum tensor Riemannian Manifold Riemann Curvature tensor Electromagnetic Field Dirac Field
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RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CONTINUUM THEORIES (Ⅳ)--SURFACE COUSERVATION LAWS 被引量:1
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作者 戴天民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第11期1245-1252,共8页
The purpose is to reestablish rather complete surface conservation laws for micropolar thermomechanical continua from the translation and the rotation invariances of the general balance law. The generalized energy-mom... The purpose is to reestablish rather complete surface conservation laws for micropolar thermomechanical continua from the translation and the rotation invariances of the general balance law. The generalized energy-momentum and energy-moment of momentum tensors are presented. The concrete forms of surface conservation laws for micropolar thermomechanical continua are derived . The existing related results are naturally derived as special cases from the results proposed in this paper . The incomplete degrees of the existing surface conservation laws are clearly seen from the process of the deduction. The surface conservation laws for nonlocal micropolar thermomechanical continua may be easily obtained via localization . 展开更多
关键词 surface conservation law micropolar thermomechanical continuum generalized energy-momentum tensor generalized energy-moment of momentum tensor
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Gravitational radiation fields in teleparallel equivalent of general relativity and their energies
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作者 Gamal G.L.Nashed 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期132-139,共8页
We derive two new retarded solutions in the teleparallel theory equivalent to general relativity (TEGR). One of these solutions gives a divergent energy. Therefore, we use the regularized expression of the gravitati... We derive two new retarded solutions in the teleparallel theory equivalent to general relativity (TEGR). One of these solutions gives a divergent energy. Therefore, we use the regularized expression of the gravitational energymomentum tensor, which is a coordinate dependent. A detailed analysis of the loss of the mass of Bondi space-time is carried out using the flux of the gravitational energy-momentum. 展开更多
关键词 teleparallel equivalent of general relativity energy-momentum tensor Bondi mass gravitational radiation
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Riemannian Space-Time, de Donder Conditions and Gravitational Field in Flat Space-Time 被引量:1
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作者 Gordon Liu 《International Journal of Astronomy and Astrophysics》 2013年第1期8-19,共12页
Let the coordinate system xi of flat space-time to absorb a second rank tensor field Φij of the flat space-time deforming into a Riemannian space-time, namely, the tensor field Φuv is regarded as a metric tensor wit... Let the coordinate system xi of flat space-time to absorb a second rank tensor field Φij of the flat space-time deforming into a Riemannian space-time, namely, the tensor field Φuv is regarded as a metric tensor with respect to the coordinate system xu. After done this, xu is not the coordinate system of flat space-time anymore, but is the coordinate system of the new Riemannian space-time. The inverse operation also can be done. According to these notions, the concepts of the absorption operation and the desorption operation are proposed. These notions are actually compatible with Einstein’s equivalence principle. By using these concepts, the relationships of the Riemannian space-time, the de Donder conditions and the gravitational field in flat space-time are analyzed and elaborated. The essential significance of the de Donder conditions (the harmonic conditions or gauge) is to desorb the tensor field of gravitation from the Riemannian space-time to the Minkowski space-time with the Cartesian coordinates. Einstein equations with de Donder conditions can be solved in flat space-time. Base on Fock’s works, the equations of gravitational field in flat space-time are obtained, and the tensor expression of the energy-momentum of gravitational field is found. They all satisfy the global Lorentz covariance. 展开更多
关键词 General Relativity Gravitation RIEMANNIAN SPACE-TIME FLAT SPACE-TIME Einstein Equations Harmonic CONDITIONS energy-momentum tensor Significance of the Coordinates Gravitational RED-SHIFT
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Bianchi Type-I Anisotropic Universe with Metric Potential in Saez-Ballester Theory of Gravitation
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作者 Md. Rezaul Karim 《Journal of Applied Mathematics and Physics》 2022年第10期3072-3082,共11页
Bianchi Type-I cosmological model in the presence of Saez-Ballester theory gravitation is studied. An exact solution of the field equation is given by considering the cosmological model yield a metric potential includ... Bianchi Type-I cosmological model in the presence of Saez-Ballester theory gravitation is studied. An exact solution of the field equation is given by considering the cosmological model yield a metric potential included with a real number. The relation between the deceleration parameter and Hubble parameter and average scale factor is used in that cosmological model. The effect of the viscosity on the entropy of the universe is utilized by energy momentum tensor with bulk viscous terms in a conservative manner. We obtained a formula for calculating the entropy of the universe in terms of viscosity and used it to compare to the study. Also, various physical and kinematical properties have been discussed. 展开更多
关键词 Bianchi Type-I Space Time Saez-Ballester Theory energy momentum tensor Bulk Viscosity Hubble and Deceleration Parameter
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The Basic Concepts and Basic Laws Relating to Matter and Gravitational Fields in Physics
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作者 Fangpei Chen 《Journal of Modern Physics》 2017年第11期1784-1794,共11页
In this work, the author applied the universal gauge field theory and Noether theorem to prove that universality exists for the Lorentz and Levi-Civita law of conservation of energy momentum tensor density. We also fo... In this work, the author applied the universal gauge field theory and Noether theorem to prove that universality exists for the Lorentz and Levi-Civita law of conservation of energy momentum tensor density. We also found that this conservation law has profound implications in physics. For example, based on this law, one can explore the origin of the matter field, and propose a new view about what is “dark energy” and what is “dark matter”. 展开更多
关键词 LAGRANGIAN MATTER FIELD GRAVITATIONAL FIELD energy-momentum tensor Density Conservation Law Origin of MATTER FIELD
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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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Physics of ferroelectric differential capacitance based upon free energy, and implications for use in electronic devices
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作者 C.M.Krowne 《Journal of Advanced Dielectrics》 CAS 2019年第1期6-21,共16页
In this paper,it is shown that for stable,steady state operation of devices typical of microwave and millimeter wave electronics,no negative differential capacitance is possible with conventional thinking.However,it m... In this paper,it is shown that for stable,steady state operation of devices typical of microwave and millimeter wave electronics,no negative differential capacitance is possible with conventional thinking.However,it may be possible,with strain engineering of materials,to obtain some if not all elements of the differential capacitance tensor which are negative.Rigorous derivations are provided based upon analyzing the physics using thermodynamic phenomenological free energy.It should be emphasized that,even with strain engineering,and possible discovery of some negative capacitive elements,stable operation will not be obtained because the thermodynamics precludes it. 展开更多
关键词 Gibbs and Helmholtz thermodynamic free energies phenomenological physical model stresses and strains negative and positive differential capacitances polarization permittivity and inverse permittivity tensors
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电磁能量-动量转化和守恒定律四维形式的一种推导 被引量:4
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作者 李子军 杨尚明 +3 位作者 钟玉荣 王子安 李作宏 崔建营 《大学物理》 北大核心 2004年第10期17-20,24,共5页
定义了电磁场的四维动量流密度张量,并将电磁能量转化和守恒定律及动量转化和守恒定律写成了四维协变形式.给出了三维电磁能量密度、能流密度、动量密度和动量流密度关于两个惯性系之间的变换关系.还给出了四维动量流密度张量与四维电... 定义了电磁场的四维动量流密度张量,并将电磁能量转化和守恒定律及动量转化和守恒定律写成了四维协变形式.给出了三维电磁能量密度、能流密度、动量密度和动量流密度关于两个惯性系之间的变换关系.还给出了四维动量流密度张量与四维电磁场张量之间的依赖关系. 展开更多
关键词 四维动量流密度张量 能量转化和守恒定律 动量转化和守恒定律 四维形式 变换关系
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重建极性连续统理论的基本定律和原理(Ⅳ)——表面守恒定律 被引量:8
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作者 戴天民 《应用数学和力学》 CSCD 北大核心 2003年第11期1101-1107,共7页
 从普遍均衡定律的平移和转动的不变性出发来重新建立较为完整的微极热力连续统的表面守恒定律,提出了广义的能量动量和能量动量矩张量· 给出了Piola型、Cauchy型和Kirchhoff型微极热力连续统的表面守恒定律的具体形式· ...  从普遍均衡定律的平移和转动的不变性出发来重新建立较为完整的微极热力连续统的表面守恒定律,提出了广义的能量动量和能量动量矩张量· 给出了Piola型、Cauchy型和Kirchhoff型微极热力连续统的表面守恒定律的具体形式· 现有的结果都可以当做是特殊情形从该结果自然地推导出来。 展开更多
关键词 表面守恒定律 微极热力连续统 广义能量动量张量 广义能量动量矩张量
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有挠引力场之能动张量密度及自旋密度的再研究 被引量:5
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作者 陈方培 《大连理工大学学报》 CAS CSCD 北大核心 1998年第2期157-161,共5页
在有挠情况下对引力场的能动张量密度及自旋密度进行了再研究,肯定了定义T(G)μidefδLG/δhiμ及C(G)μijdef-2δLG/δΓijμ的合理性,导出了引力波虽存在但不携带能量、动量及自旋的结论.
关键词 引力场 能动张量密度 自旋密度 挠率
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Melvin磁宇宙中Schwarzschild黑洞外部区域的电磁场能量动量张量 被引量:1
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作者 石东平 程正富 文毫渝 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第1期79-82,共4页
对Melvin磁宇宙中球对称质量外部区域的电磁场能量动量张量进行了研究, 给出电磁场能量的分布规律;然后以均匀磁场中的Schwarzschild黑洞为例, 通过数值计算出球对称引力场对均匀磁场能量分布的影响. 结果表明, 时空的弯曲会使均匀磁场... 对Melvin磁宇宙中球对称质量外部区域的电磁场能量动量张量进行了研究, 给出电磁场能量的分布规律;然后以均匀磁场中的Schwarzschild黑洞为例, 通过数值计算出球对称引力场对均匀磁场能量分布的影响. 结果表明, 时空的弯曲会使均匀磁场的能量增大. 展开更多
关键词 Melvin磁宇宙 电磁场能量动量张量 Sehwarzsehild黑洞
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自作用电子场的能量特性 被引量:2
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作者 冉扬强 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第4期406-411,共6页
讨论了在非相对论近似下自组织带电物质的量子力学理论.得到了自作用电子基本运动方程的非相对论极限,建立了非相对论自作用电子的Lagrange函数和Hamilton函数,研究了在非相对论近似下自作用电子场的能量特性.
关键词 自作用 带电粒子 电子场 量子力学 能量特性
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电磁场能量动量张量的双矢势对偶理论 被引量:6
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作者 熊晓军 李康 +1 位作者 傅明星 王剑华 《陕西工学院学报》 2005年第1期87-90,共4页
在考虑有磁荷存在的情况下,引入了电磁场双四维势的描述方法。给出了场强与双四维势的关系,并且从Euler-Lagrange方程出发,推导出了具有电磁对偶对称性的Maxwell方程;讨论了具有对偶对称性的电磁场能量动量密度张量以及它们的特性;最后... 在考虑有磁荷存在的情况下,引入了电磁场双四维势的描述方法。给出了场强与双四维势的关系,并且从Euler-Lagrange方程出发,推导出了具有电磁对偶对称性的Maxwell方程;讨论了具有对偶对称性的电磁场能量动量密度张量以及它们的特性;最后,证明了有磁源存在情况下电磁场的能量和动量守恒定律。 展开更多
关键词 电磁对偶性 MAXWELL方程 双矢势 能量动量张量
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荷磁矩中子星外部的电磁场能量动量张量 被引量:1
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作者 石东平 吴张晗 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2004年第3期69-73,共5页
利用王永久等人所得到的具有磁矩的球对称质量外部的引力场度规和电磁势的表达式,计算出了球对称质量外部的电磁场量动量张量。数值计算结果和分布曲线表明,时空的弯曲将引起磁偶极子电磁场能量的增加。
关键词 磁矩 球对称质量 引力场度规 电磁势 电磁场能量动量张量 中子星
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对偶电磁场理论的能量动量张量 被引量:1
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作者 刘芳丽 李康 《杭州师范学院学报(自然科学版)》 CAS 2005年第5期368-371,396,共5页
回顾了经典电磁对偶场论的双四维势描述形势,分析了该描述情形下电磁场的能动量张量,最后在四维势的理论框架下推导出电磁对偶广义Lorentz公式.
关键词 电磁场 能动量张量 Lorentz公式
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