tag:blogger.com,1999:blog-8082954141980125536.post7656235451569311975..comments2008-01-23T07:41:06.705-05:00rschttp://www.blogger.com/profile/06357099531993534337noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-8082954141980125536.post-39610196191986791422008-01-23T07:41:00.000-05:002008-01-23T07:41:00.000-05:002008-01-23T07:41:00.000-05:00A more detailed endnote to that section reads: <BR/><BR/>Corrections are of many sorts, and include effects due to the motion of satellites, the lower gravitational field at the height of the satellites, and the rotatory motion of the earth. The relativistic component of the Doppler shift is <I>v</I>^2/2<I>c</I>^2, which for satellite velocities is about seven millionths of a second per day. Because the speed of light is so much faster than the speed of the satellites, most of general relativity need not be taken into account, but the equivalence principle that is part of general relativity is significant. (The equivalence principle says that there is no way to distinguish the physics of a freely falling box from the same box without a gravitational field.) A more rigorous analysis would take into account (inter alia) that the satellites' orbit is not always in the same gravitational field, that the earth observer may be moving on the surface of the earth, that the earth's gravitational field is not the same everywhere on the earth's surface, that the sun's gravitational field affects the earth clock and the satellite clock differently, and that the apparent velocity of light is altered by the earth's gravitational field.rschttp://www.blogger.com/profile/09576271159839887762noreply@blogger.com