Abstract
The uniform motion of the center of mass of a bounded perfect fluid mass up to the first post-Newtonian approximation of general relativity is derived, by proving that the total linear momentum of the fluid can be put in the form of the total time-derivative of a certain function. The same formula applies in the case that the fluid mass is composed of N perfect fluid bodies of finite dimensions. In the latter case, if we disregard terms of O(L/D), where L are the linear dimensions and D the mutual distances of the bodies, we can define a conserved mass and a center of mass for each body in the post-Newtonian approximation, such that the equations of the motion of the center of mass of the system reduce to those of a system of N point masses. The mass so defined is the total mass-energy of each body, measured in a frame comoving with the body. Subject heading: relativity
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
