以广义相对论为例谈实验检验的总体方案设计

以广义相对论为例，论述了如何根据物理理论的逻辑体系设计实验，以检验理论的正确性，对于广义相对论，检验实验应包括对等效原理的检验实验，对牛顿极限的检验实验，以及对广义相对论推论的检验实验。     

《相对论、宇宙与时空》连载⑤——爱因斯坦与狭义相对论(下)

4 广义相对论的实验验证 爱因斯坦发表广义相对论的时候,求出了场方程的一些近似解.他提出了3个检验广义相对论的实验:1)引力红移;2)轨道进动;3)光线偏折[1,2,4-17].     

关于广义相对论的第四个验证

广义相对论的三大验证(引力、红移、光线偏折和水星近日点进动)是爱因斯坦在建立广义相对论时提出来的.1964年Shapiro提出了第四个检验,即“雷达回波时间延迟”实验[1].后来,实验结果以越来越高的精度证明了广义相对论的这个预言.本文的目的是介绍时间延迟效应的理论计算和实验     

爱因斯坦与广义相对论的诞生——纪念广义相对论发表100周年

介绍了爱因斯坦建立广义相对论的伟大贡献.他最先发现了等效原理,最先指出万有引力本质上是时空弯曲的几何效应.爱因斯坦也是最先给出广义相对论基本方程——场方程的人.他提出的检验广义相对论的3个重要实验已被观测所证实.爱因斯坦是广义相对论的唯一创建者.     

广义相对论与有关现代引力问题

1916年,爱因斯坦发表了广义相对论,提供了一种引力理论.然而,在文章发表后的三、四十年中,由于实验验证很少,应用不广,数学上又较为复杂,因此对广义相对论有许多不同意见和争论,也没有得到物理学界的足够的重视. 但是,近二十年来现代生产和科学技术的大发展,为广义相对论的实验     

量子引力和弦论在中国

直到20世纪60年代,爱因斯坦的广义相对论一直是理论物理中理论色彩最浓的一个分支,那时广义相对论的主要实验验证是水星近日点进动、太阳引力场中的光线弯曲、引力红移。直到宇宙学和涉及强引力场的一些天体物理问题成为实验观测对象后,广义相对论才成为和其他物理理论（如粒子物理）类似的学科。与此同时,人们开始尝试将引力和量子力学结合起来,这就是著名的量子引力或引力量子化问题。     

引力场的二分量理论和验证广义相对论的新实验

美国斯坦福大学以W.Fairbank为首的研究组,正在考虑验证广义相对论的极为精密的新实验. 从1915年爱因斯坦发表广义相对论以来,通过水星近日点的移动,光线在引力场中的折射及光谱线的红移等现象的观测,验证了广义相对论的正确性.但是,上述新实验是以最近提出的引力场二分量理论来验证广义相对论的一种新尝试. 众所周知,电磁场中有电场和磁场.与此相似,可认为引力场也由两个分量所构成.由于牛顿势和库仑势在形式上是相同的,因而牛顿势对应于电场势.根据牛顿引力理论,不存在对应于磁场的分量.而按上述理论,在广义相对论所讨论的引力场中必然存…     

《广义相对论入门讲座》连载——狭义相对论

广义相对论诞生至今已快100年了,然而了解此领域的人依然十分稀少.一般人认为广义相对论与实验联系较少,缺乏科研上的动力,而且在物理理解和数学运算上都十分困难,需要付出巨大努力才能进入这一用处不大的领域.然而,近年来随着中子星、黑洞、引力波和宇宙学领域的发展,广义相对论找到了广阔的应用空间,越来越多的人感到了对广义相对论知识的需求.其实,广义相对论也不像一般人想象的那样难学.数学上的困难源于一般人不熟悉黎曼几何与张量分析.作者从长期的教学中体会到,实际上可以采用"急用先学,立竿见影"的方式,用较短的时间把初学者引入广义相对论和黎曼几何的大门,使他们不仅了解广义相对论的物理思想,学会初步的运算,而且能看懂相对论天体物理学的文献,并尝试参与广义相对论及相关领域的初步研究.有志于钻研广义相对论的人,还可以在此基础上,"干中学",在出科研成果的同时,不断加深对广义相对论的理解,逐步成长为这一领域的教师和科研专家.本讲座就是这方面的一次尝试,望对广义相对论有兴趣并有志于学习它的人,参与这一进入科研前沿的尝试.本讲座共分8讲,目录如下:狭义相对论;广义相对论的物理基础;黎曼几何中的张量;度规张量;时间与空间;测地线、联络、曲率与挠率;爱因斯坦场方程;广义相对论的实验验证.本刊将以连载的形式分8期刊登.     

广义相对论简介--工科大学物理课讲授广义相对论的一种方案

用普通物理语言简介广义相对论的基本观点,等效原理,时间和空间,对一种引力场－史瓦西场中的固有时和真实距离进行了计算。     

月球尘埃影响对广义相对论的验证

在《对广义相对论更精确的实验检验》[2]一文中叙述了科学家们用发射激光到安置在月亮上的5个反射器来验证等效原理从而间接检验广义相对论的阿波罗(Apollo)测月计划.在此实验中,微弱的光线是一个问题.     

广义相对论的旋量和复矢量形式

本文利用Cartan外微分法,给出结构方程的旋量形式,从而自然得出Newman-Penrose方程。进而由旋量空间出发,利用sl(2C)代数引出广义相对论的复矢量形式。通常采用的Cahen-Debever-Defrise复矢量形式及Brans复矢量形式是这里的特殊情形。这样,便从么模群SL(2C)及其李代数sl(2C)的角度得到了引力场复矢量表述的普遍形式,并把旋量和复矢量形式统一了起来。     

The confrontation between general relativity and experiment

We review the experimental evidence for Einstein’s general relativity. Tests of the Einstein equivalence principle support the postulates of curved space-time and bound variations of fundamental constants in space and time, while solar system experiments strongly confirm weak-field general relativity. The binary pulsar provides tests of gravitational wave damping and of strong-field general relativity. Future experiments, such as the gravity probe B gyroscope experiment, a satellite test of the equivalence principle, and tests of gravity at short distance to look for extra spatial dimensions could further constrain alternatives to general relativity. Laser Interferometric Gravitational Wave Observatories on Earth and in space may provide new tests of scalar-tensor gravity and graviton-mass theories via the properties of gravitational waves.     

General Relativistic Shift in Plasma Frequency due to a Slowly Rotating Compact Star

We investigate the effects of a slowly rotating compact gravitational source on plasma oscillations using the gravitoelectromagnetic approximation to the general theory of relativity. It is shown that there is a shift in the plasma frequency and hence in the refractive index of the plasma due to the gravitomagnetic force. Estimates for the difference in frequency of radially transmitted electromagnetic signals are given for typical compact star candidates. The proposed shift provides a new test of general theory of relativity in the slow rotation approximation.     

Equivalence principle and light deflection

The deflection of light is discussed with regard to its significance for the structure of general relativity. It is argued that this effect is no consequence of the equivalence principle, but is a real test for general relativity.Einstein's elevator model andFock's criticism of the equivalence principle are investigated.     

The physical meaning of canonical quantization in terms of reference systems

The canonical approach to general relativity in terms of reference systems is discussed to show that Einstein's principles of equivalence and general relativity imply the physical insignificance of quantized general relativity. In particular it is demonstrated that even the (anholonomic) flat-space canonical formalism leads to physically uninterpretable results. This lack of quantum content of general relativity is reflected by Rosenfeld's uncertainty relations and can especially be removed by modifying general relativity in the spirit of classical Einstein-Cartan theory with teleparallelism.     

Interaction,not gravitation

Cannon and Jensen assert that data from different national time laboratories give a test of the interaction interpretation of special relativity theory. That interpretation is to be applied, however, to clocks in relative uniform motion, and therefore is not tested by the time-rate effects associated with different terrestrial locations of clocks. Those effects are described by the general theory of relativity, and arise with differences in gravitational potential and state of circular motion of the clocks. An argument by the authors against invariance of entropy clocks, on grounds of neglect of relativity of simultaneity, is also criticized.     

A note on the computation of geometrically defined relative velocities

We discuss some aspects about the computation of kinematic, spectroscopic, Fermi and astrometric relative velocities that are geometrically defined in general relativity. Mainly, we state that kinematic and spectroscopic relative velocities only depend on the 4-velocities of the observer and the test particle, unlike Fermi and astrometric relative velocities, that also depend on the acceleration of the observer and the corresponding relative position of the test particle, but only at the event of observation and not around it, as it would be deduced, in principle, from the definition of these velocities. Finally, we propose an open problem in general relativity that consists on finding intrinsic expressions for Fermi and astrometric relative velocities avoiding terms that involve the evolution of the relative position of the test particle. For this purpose, the proofs given in this paper can serve as inspiration.     

孪生子效应析疑

说明孪生子效 一个实验上和理论上都已解决了问题，通过一个具的例阐明孪生子效应的物理本质，从而指出不能观测到“返老还童”的现象，并对享生长子效应与广义相对的关系作一些讨论。     

Cylindrically symmetric Brans–Dicke–Maxwell solutions

We investigate cylindrically symmetric vacuum solutions with both null and non-null electromagnetic fields in the framework of the Brans–Dicke theory and compare these solutions with some of the well-known solutions of general relativity for special values of the parameters of the resulting field functions. We see that, unlike general relativity where the gravitational force of an infinite and charged line mass acting on a test particle is always repulsive, it can be attractive or repulsive for Brans–Dicke theory depending on the values of the parameters as well as the radial distance from the symmetry axis.     

Paths of spinning particles in general relativity as geodesics of an Einstein connection

This paper deals with the Papapetrou-Pirani equations of motion for a spinning test particle in general relativity. The motion of the center of mass can be represented by the geodesic equation of an affine connection that is the sum of the Christoffel connection and a tensor that depends on the Riemann-Christoffel curvature tensor, the mass of the particle, its 4-velocity, and its spin tensor. The connection is not unique, and here it is chosen to satisfy one of the basic geometrical principles of Einstein's unified field theory: The symmetric part of the fundamental tensor of the geometry is specified to be the metric tensor of general relativity. The special case of conformally flat space-times is discussed.