Article Theoretical Physics

Chinese Science Bulletin

, Volume 58, Issue 4, pp 474-477

Open Access This content is freely available online to anyone, anywhere at any time.

Observational evidences for the speed of the gravity based on the Earth tide

  • KeYun TangAffiliated withInstitute of Geology and Geophysics, Chinese Academy of SciencesNational Astronomical Observatory, Chinese Academy of Sciences Email author 
  • , ChangCai HuaAffiliated withInstitute of Geophysics, China Earthquake Administration
  • , Wu WenAffiliated withInstitute of Geology and Geophysics, Chinese Academy of Sciences
  • , ShunLiang ChiAffiliated withUniversity of Chinese Academy of Sciences
  • , QingYu YouAffiliated withInstitute of Geology and Geophysics, Chinese Academy of Sciences
  • , Dan YuAffiliated withNetwork Center of China Earthquake Administration

Abstract

We have found that the current practical Newtonian formula for the gravity tide of the Earth implies a hypothesis that gravity travels at the speed of light; furthermore, we have derived and solved the propagation equation of gravity using the observation data of Earth tides from Shiquanhe and Wushi, after correction of phase lag due to the anelasticity of the Earth, and found that the speeds of gravity are from 0.93 to 1.05 times the speed of light with a relative error of about 5%. This provides first set of strong evidences to show that the speed of gravity is the same as the speed of light.

Keywords

Earth tide apparent position phase lag speed of light speed of gravity propagation equation of gravity