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Bach-Einstein Gravitational Field Equations as a Perturbation of Einstein Gravitational Field Equations
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作者 Fathy Ibrahim Abdel-Bassier Ahmed Fouad Abdel-Wahab Fayrouz Mostafa Abdel-Maboud 《Applied Mathematics》 2022年第12期1022-1032,共11页
The Bach equations are a version of higher-order gravitational field equations, exactly they are of fourth-order. In 4-dimensions the Bach-Einstein gravitational field equations are treated here as a perturbation of E... The Bach equations are a version of higher-order gravitational field equations, exactly they are of fourth-order. In 4-dimensions the Bach-Einstein gravitational field equations are treated here as a perturbation of Einstein’s gravity. An approximate inversion formula is derived which admits a comparison of the two field theories. An application to these theories is given where the gravitational Lagrangian is expressed linearly in terms of R, R<sup>2</sup>, |Ric|<sup>2</sup>, where the Ricci tensor Ric = R<sub>αβ</sub>dx<sup>α</sup>dx<sup>β</sup> is inserted in some formulas which are of geometrical or physical importance, such as;Raychaudhuri equation and Tolman’s formula. 展开更多
关键词 gravitational Theory Higher Order Gravity Buchdahl’s Formula Bach-einstein gravitational field equations Raychaudhuri equation Tolman’s Formula
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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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The Singularities of Gravitational Fields of Static Thin Loop and Double Spheres Reveal the Impossibility of Singularity Black Holes 被引量:2
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作者 Xiaochun Mei 《Journal of Modern Physics》 2013年第7期974-982,共9页
In the classical Newtonian mechanics, the gravity fields of static thin loop and double spheres are two simple but foundational problems. However, in the Einstein’s theory of gravity, they are not simple. In fact, we... In the classical Newtonian mechanics, the gravity fields of static thin loop and double spheres are two simple but foundational problems. However, in the Einstein’s theory of gravity, they are not simple. In fact, we do not know their solutions up to now. Based on the coordinate transformations of the Kerr and the Kerr-Newman solutions of the Einstein’s equation of gravity field with axial symmetry, the gravity fields of static thin loop and double spheres are obtained. The results indicate that, no matter how much the mass and density are, there are singularities at the central point of thin loop and the contact point of double spheres. What is more, the singularities are completely exposed in vacuum. Space near the surfaces of thin loop and spheres are highly curved, although the gravity fields are very weak. These results are inconsistent with practical experience and completely impossible. By reasonable analogy, black holes with singularity in cosmology and astrophysics are something illusive. Caused by the mathematical description of curved space-time, they do not exist in real world actually. If there are black holes in the universe, they can only be the types of the Newtonian black holes without singularities, rather than the Einstein’s singularity black holes. In order to escape the puzzle of singularity thoroughly, the description of gravity should return to the traditional form of dynamics in flat space. The renormalization of gravity and the unified description of four basic interactions may be possible only based on the frame of flat space-time. Otherwise, theses problems can not be solved forever. Physicists should have a clear understanding about this problem. 展开更多
关键词 General Relativity The einstein’s equation of Gravity field Axially Symmetrical Solutions SINGULARITY Kerr METRIC Kerr-Newman METRIC gravitational field of Static Thin LOOP gravitational field of Double SPHERES Black Hole Quasar MECO
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Maxwell-Proca Fields in Relativistic Astrophysical Compact Objects
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作者 Zoran Pazameta 《Journal of Modern Physics》 2013年第8期240-244,共5页
A general-relativistic model is formulated for hypothetical ultra-compact astrophysical objects composed of fluid infused with charges carrying a generalized massless Maxwell-Proca field. The chosen interior metric ha... A general-relativistic model is formulated for hypothetical ultra-compact astrophysical objects composed of fluid infused with charges carrying a generalized massless Maxwell-Proca field. The chosen interior metric has the algebraic property that;the fluid consequently possesses a negative pressure which halts gravitational collapse and establishes hydrostatic equilibrium. For an object containing a global distribution of non-interacting Maxwell-Proca charges, it is shown that physical considerations define the relationship between the charge density and the metric function uniquely, corroborating an earlier finding (for an electrostatic distribution of charge) that the interior field must increase with radial distance and the exterior field necessarily follows an inverse-square law. For the case of a charged fluid envelope surrounding a core of uncharged fluid, numerous solutions are possible. Assuming the interior field to vary as rn and requiring its strength to increase with radial distance while the charge density decreases, the range of values for n is found to be 0 n ≤ 1 (where n is not necessarily an integer) with n = 1 denoting the special case of a continuous distribution of charge. For both continuous and stratified charge distributions, the exterior field is found to decrease as 1/r2?regardless of the interior field’s dependence on r. 展开更多
关键词 GRAVITATION Compact Objects einstein equationS Maxwell-Proca fieldS
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Gravitational Space-Time Curve Generation via Accelerated Charged Particles
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作者 Edward A. Walker 《Journal of Modern Physics》 2016年第9期863-874,共12页
A force with an acceleration that is equal to multiples greater than the speed of light per unit time is exerted on a cloud of charged particles. The particles are resultantly accelerated to within an infinitesimal fr... A force with an acceleration that is equal to multiples greater than the speed of light per unit time is exerted on a cloud of charged particles. The particles are resultantly accelerated to within an infinitesimal fraction of the speed of light. As the force or acceleration increases, the particles’ velocity asymptotically approaches but never achieves the speed of light obeying relativity. The asymptotic increase in the particles’ velocity toward the speed of light as acceleration increasingly surpasses the speed of light per unit time does not compensate for the momentum value produced on the particles at sub-light velocities. Hence, the particles’ inertial mass value must increase as acceleration increases. This increase in the particles’ inertial mass as the particles are accelerated produce a gravitational field which is believed to occur in the oscillation of quarks achieving velocities close to the speed of light. The increased inertial mass of the density of accelerated charged particles becomes the source mass (or Big “M”) in Newton’s equation for gravitational force. This implies that a space-time curve is generated by the accelerated particles. Thus, it is shown that the acceleration number (or multiple of the speed of light greater than 1 per unit of time) and the number of charged particles in the cloud density are surjectively mapped to points on a differential manifold or space-time curved surface. Two aspects of Einstein’s field equations are used to describe the correspondence between the gravitational field produced by the accelerated particles and the resultant space-time curve. The two aspects are the Schwarzchild metric and the stress energy tensor. Lastly, the possibility of producing a sufficient acceleration or electromagnetic force on the charged particles to produce a gravitational field is shown through the Lorentz force equation. Moreover, it is shown that a sufficient voltage can be generated to produce an acceleration/force on the particles that is multiples greater than the speed of light per unit time thereby generating gravity. 展开更多
关键词 Charged Particles Accelerated Particles Inertial Mass gravitational Force einstein’s field equations Space-Time Manifold Schwardchild Metric Stress Energy Tensor Surjective Mapping Lorentz Force
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等效原理与引力场的能量-动量表示 被引量:3
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作者 邓昭镜 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2008年第9期11-15,共5页
等效原理是作为时-空背景的引力场的独特规律,又是引力场籍以区别于所有其它物质场(或非背景场)的最独特的性质.正因为如此,和所有其它物质场不同,引力场的能量-动量不可能有张量表示,或者说不可能定域化.对此学术界曾引发了一场争论,... 等效原理是作为时-空背景的引力场的独特规律,又是引力场籍以区别于所有其它物质场(或非背景场)的最独特的性质.正因为如此,和所有其它物质场不同,引力场的能量-动量不可能有张量表示,或者说不可能定域化.对此学术界曾引发了一场争论,提出了引力场能量-动量的各种表述.纵观各种表述,只有Landau提出的能量-动量赝张量表示才是最能反映等效原理要求的表述.因此,就比较而言,Landau和Hans提出的关于引力场的能量-动量赝张量表述是更为合理的表述.重温Landau和Hans关于引力场能量-动量赝张量表述,以阐明如何依靠等效原理来探求纯引力场的能量-动量表述. 展开更多
关键词 等效原理 守恒律 能量-动量张量 能量-动量赝张量
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关于GPS系统“相对论修正”问题的讨论 被引量:2
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作者 黄志洵 《中国传媒大学学报(自然科学版)》 2020年第6期1-13,共13页
GPS的运转依赖于绕地球旋转的卫星上的原子钟的精确性。所谓相对论性修正包括狭义相对论(SR)修正(-7μs/天)和广义相对论(GR)修正(45.9μs/天),故净增量为约38μs/天。相对论性预期是以时间延缓及引力势理论为基础的。在Lorentz理论中,... GPS的运转依赖于绕地球旋转的卫星上的原子钟的精确性。所谓相对论性修正包括狭义相对论(SR)修正(-7μs/天)和广义相对论(GR)修正(45.9μs/天),故净增量为约38μs/天。相对论性预期是以时间延缓及引力势理论为基础的。在Lorentz理论中,时间延缓由动体的绝对运动引起。相对于静止的时钟,绝对速度大的时钟变慢;这是Lorentz以太论中的时间延缓。但在SR中用动体相对速度取代绝对速度,情况完全不同。Einstein是以不同观察者参考系的相对运动取代观察者与以太的关系,来解释长度缩短和时间延缓。因而产生了许多悖论质疑SR的自洽性,最著名的是P.Langevin于1911年提出的双生子佯谬。多年来的众多研究讨论显示,SR存在逻辑上的不自洽,亦缺少真正确定的实验证实。由此可以理解欧洲核子研究中心(CERN)的著名科学家John Bell在1985年所说的话:"我想回到Einstein之前,即Poincarè和Lorentz",此外,本文着重指出引力势概念在理论上和实践中都不那么重要,因为它缺乏实验基础。这与电磁学中的情况并不相同。众所周知,Maxwell方程组建筑在若干实验定律的基础上,电磁势概念很重要。然而类电磁引力场方程组不满足这条件,故它不被事实所支持。再者,Einstein引力场方程(EGFE)是GR理论的基本方程,但它的推导有假设和拼凑的作法。引力场的物理效果被认定由Riemann空间的度规张量体现,需要知道度规场分布的规律。但由于没有可作依据的实际观测知识,推导引力场方程就用猜测性的推理。基于这些理由,我们相信"没有相对论就没有GPS"的说法是错误的。GPS的时空结构其实与Galilei、Newton和Maxwell理论相同。 展开更多
关键词 全球定位系统 狭义相对论(SR) 广义相对论(GR) 时间延缓 误差修正 引力场方程
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对广义相对论的研究和讨论 被引量:1
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作者 黄志洵 《中国传媒大学学报(自然科学版)》 2022年第1期64-80,共17页
Einstein引力场方程(EGFE)是广义相对论(GR)中最重要的公式,但EGFE有明显的假设和拼凑的痕迹。如何表达“引力使时空弯曲”(或“时空弯曲造成了引力”)是根本性的待决问题。引力场的物理效果被认定由Riemann空间的度规张量体现,需要知... Einstein引力场方程(EGFE)是广义相对论(GR)中最重要的公式,但EGFE有明显的假设和拼凑的痕迹。如何表达“引力使时空弯曲”(或“时空弯曲造成了引力”)是根本性的待决问题。引力场的物理效果被认定由Riemann空间的度规张量体现,需要知道度规场分布的规律。但由于没有可作依据的实际观测知识,推导EGFE就用猜测性推理。也就是说,物理学实验从未提供过显示引力几何化的(只有Riemann几何才能表现的)知识和规律,Einstein即贸然决定G_(μυ)=R_(μυ)-g_(μυ)R/2≡κT_(μυ)。Einstein引力场理论不是令人放心的可靠理论,它无法取代Newton的引力理论。Newton理论建立在Kepler和Galileo实验定律所包含的无数实验观测结果之上,经过了几百年科学实验和工程实践的检验,并继续在科学和工程中接受广泛的检验,从来没有一例证明Newton引力定律的错误。相反,GR从基本假设到理论框架都存在根本性的不自洽或违背基本的物理事实。Einstein的弯曲时空引力理论是依靠想象建立的,不可能与建立在经验基础上的Newton引力理论达到一致。作为一个理论系统,GR的内在逻辑混乱,因果关系颠倒。例如GR有一个结果说,引力场传播速度是光速,引力波传播速度也是光速;这些都是错误的。如引力以有限速度c传播,将有扭矩作用于行星,则绕太阳运行的行星将变得不稳定。如果太阳产生的引力是以光速向外传播,那么当引力走过日地间距而到达地球时,后者已前移了与8.3min相应的距离。这样一来,太阳对地球的吸引同地球对太阳的吸引就不在同一条直线上了;这使绕太阳运行的星体轨道半径增大,在1200年内地球对太阳的距离将加倍。但在实际上地球轨道是稳定的,故可断定引力传播速度远大于光速。由此可见,GR不能处理引力问题。实际上,正是基本的物理学原理决定了不会有引力波。引力是最早知道的物理相互作用,但它是唯一不能与量子理论相容的作用。人们说GR成功地描述了引力,但这是错误的。GR也叫几何动力学,基本方程用几何项写出公式,这与量子理论有根本性冲突。另外,GR使宇宙学陷入混乱,大爆炸理论、黑洞物理均为例证。基于上述理由,我们认为Einstein的广义相对论是不正确的。 展开更多
关键词 广义相对论 einstein引力场方程 弯曲时空 引力波 量子理论
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关于引力场方程的一个谐和解及有关问题
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作者 余招贤 崔世治 《中山大学学报(自然科学版)》 CAS CSCD 1993年第3期109-112,共4页
本文讨论了爱因斯坦场方程在谐和条件下的真空球对称解,对近年提出的关于谐和坐标的物理意义的新观点,提出有待斟酌的问题.
关键词 爱因斯坦场 谐和条件 引力场方程
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荷电柱状天体外部度规的计算
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作者 吕君丽 周启煌 《湖南师范大学自然科学学报》 CAS 1989年第1期28-35,共8页
本文从静态轴对称度规的一般表达式ds^2=-e^(2u)(dx^0)~2+e^(-2u)[e^(2k)(dx^1)~2+e^(2k)(dx^2)~2+ρ~2(dx^3)~2]出发,结合Einstein-Maxwell方程组,应用渐近平直条件求出弯曲空间中的静电场,解出了荷电柱状天体(静态)外部度规的四级近... 本文从静态轴对称度规的一般表达式ds^2=-e^(2u)(dx^0)~2+e^(-2u)[e^(2k)(dx^1)~2+e^(2k)(dx^2)~2+ρ~2(dx^3)~2]出发,结合Einstein-Maxwell方程组,应用渐近平直条件求出弯曲空间中的静电场,解出了荷电柱状天体(静态)外部度规的四级近似解。 展开更多
关键词 柱状天体 引力场 度规 计算
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引力场致钟慢效应的计算分析
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作者 曹跃祖 李福芸 李柳青 《北京印刷学院学报》 2009年第4期75-76,共2页
相对于观察者远去的星系,其光谱频率除多普勒红移外,在脱离引力场束缚时,还存在着频率的引力场红移,实验测得的是两种效果的综合。由于引力场中的时空弯曲,经由广义相对论时空变换关系,可以得到红移量的定量结果。其与爱因斯坦质能方程... 相对于观察者远去的星系,其光谱频率除多普勒红移外,在脱离引力场束缚时,还存在着频率的引力场红移,实验测得的是两种效果的综合。由于引力场中的时空弯曲,经由广义相对论时空变换关系,可以得到红移量的定量结果。其与爱因斯坦质能方程所推证的结论一致,证明光在离开引力场时,其频率减小。这从不同的理论侧面检验了广义相对论的正确性。其结果在剔除多普勒频移效应后,与星际空间观察结果相符。 展开更多
关键词 引力场 钟慢效应 引力红移 爱因斯坦质能方程
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自膨胀与自收缩星系的演化
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作者 邓昭镜 陈华林 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第7期46-50,共5页
根据Einstein场方程确立的星系(星云、星系或恒星)在自膨胀或自收缩过程中的能量变化,提出了星系在其自膨胀和自收缩过程中的热力学模型.
关键词 einstein场方程 量纲平衡 工作物质 热机循环
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爱因斯坦与广义相对论的诞生(续)——纪念广义相对论发表100周年
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作者 赵峥 《大学物理》 北大核心 2015年第12期1-5,共5页
11爱因斯坦与希尔伯特的合作与竞争 在广义相对论诞生前后的几个月内,爱因斯坦与希尔伯特之间既进行了合作探讨,又产生了竞争([14,15]).在与爱因斯坦的讨论中,希尔伯特对爱因斯坦的新理论产生了兴趣,他也开始寻找场方程的正确形式.希... 11爱因斯坦与希尔伯特的合作与竞争 在广义相对论诞生前后的几个月内,爱因斯坦与希尔伯特之间既进行了合作探讨,又产生了竞争([14,15]).在与爱因斯坦的讨论中,希尔伯特对爱因斯坦的新理论产生了兴趣,他也开始寻找场方程的正确形式.希尔伯特不愧是数学大师,他很快赶了上来.在爱因斯坦把自己的最终论文投给杂志社的同时,希尔伯特也投了稿. 展开更多
关键词 广义相对论 希尔伯特 引力红移 牛顿理论 场方程 数学大师 弯曲时空 时空曲率 狭义相对论 时空弯曲
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引力波及激光观测原理
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作者 韩潇 刘宇星 《物理与工程》 2017年第4期70-74,共5页
近期引力波话题火热,为使本科生对引力波有系统的了解,本文由爱因斯坦经典引力理论出发,考虑在远离场源的弱场近似,细致推导得到波速为光速、在空间上以横波形式传播的引力波的波动方程,并且指出引力波只存在两种独立的极化状态,即引力... 近期引力波话题火热,为使本科生对引力波有系统的了解,本文由爱因斯坦经典引力理论出发,考虑在远离场源的弱场近似,细致推导得到波速为光速、在空间上以横波形式传播的引力波的波动方程,并且指出引力波只存在两种独立的极化状态,即引力波两个独立的偏振方向。之后对激光观测引力波实验的理论进行合理性分析。得出装有法布里-珀罗腔结构的迈克耳孙干涉仪具备观测引力波能力的结论。 展开更多
关键词 引力波 爱因斯坦引力场方程 弱场近似 激光观测
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Theory of a Mach Effect Thruster I
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作者 Heidi Fearn Adam Zachar +1 位作者 Keith Wanser James Woodward 《Journal of Modern Physics》 2015年第11期1510-1525,共16页
The Mach Effect Thruster (MET) is a propellant—less space drive which uses Mach’s principle to produce thrust in an accelerating material which is undergoing mass—energy fluctuations, [1]-[3]. Mach’s principle is ... The Mach Effect Thruster (MET) is a propellant—less space drive which uses Mach’s principle to produce thrust in an accelerating material which is undergoing mass—energy fluctuations, [1]-[3]. Mach’s principle is a statement that the inertia of a body is the result of the gravitational interaction of the body with the rest of the mass-energy in the universe. The MET device uses electric power of 100 - 200 Watts to operate. The thrust produced by these devices, at the present time, are small on the order of a few micro-Newtons. We give a physical description of the MET device and apparatus for measuring thrusts. Next we explain the basic theory behind the device which involves gravitation and advanced waves to incorporate instantaneous action at a distance. The advanced wave concept is a means to conserve momentum of the system with the universe. There is no momentun violation in this theory. We briefly review absorber theory by summarizing Dirac, Wheeler-Feynman and Hoyle-Narlikar (HN). We show how Woodward’s mass fluctuation formula can be derived from first principles using the HN-theory which is a fully Machian version of Einstein’s relativity. HN-theory reduces to Einstein’s field equations in the limit of smooth fluid distribution of matter and a simple coordinate transformation. 展开更多
关键词 MACH EFFECT Drive Transient Mass Fluctuations Weak field Limit GRAVITATION Modified (PPN) Parameterized Post NEWTONIAN Approximation Linearized einstein equations Gravitoelectromagnetism
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