On the measurement for the speed of gravity  

作　　者：Linxia Liu Chenggang Shao 

机构地区：[1]Department of Electronics and Communication Engineering,Henan Mechanical and Electrical Engineering College [2]School of Physics, Huazhong University of Science and Technology

出　　处：《Chinese Science Bulletin》2014年第9期828-832,共5页

基　　金：supported by the National Natural Science Foundation of China(11275057)

摘　　要：Newton’s law of gravity is a theory of instantaneous action at a distance.However,Einstein’s general relativity states that the speed of gravity equals the speed of light,which is finite.Therefore,it is a worthy problem to discuss if Newton’s law of gravity needs modification,when studying and observing the gravitational tidal.In this paper,it is shown that the Newton’s law of gravity is fully applicable in the framework of general relativity.Based on the post-Newtonian approximation,we find that the observable effect for the speed of gravity is irrelevant to the velocity of a moving source,but it is dependent on its acceleration.In general,the effect of the speed of gravity is so weak that today’s any astronomical observations,including the sun tidal observations,can not confirm that the gravitational field travels at the speed of light.Newton＇s law of gravity is a theory of instan- taneous action at a distance. However, Einstein＇s general relativity states that the speed of gravity equals the speed of light, which is finite. Therefore, it is a worthy problem to discuss if Newton＇s law of gravity needs modification, when studying and observing the gravitational tidal. In this paper, it is shown that the Newton＇s law of gravity is fully applicable in the framework of general relativity. Based on the post-Newtonian approximation, we find that the observable effect for the speed of gravity is irrelevant to the velocity of a moving source, but it is dependent on its acceleration. In general, the effect of the speed of gravity is so weak that today＇s any astronomical observations, including the sun tidal observations, can not confirm that the gravitational field travels at the speed of light.

关 键 词：重力定律 速度 广义相对论 牛顿定律 测量 引力场 爱因斯坦 重力潮汐 

分 类 号：O314[理学—一般力学与力学基础]