On Tue, Oct 13, 2020 at 1:20 AM Alan Grayson <agrayson2...@gmail.com> wrote:
*> How does gravity cause the difference between what the theories predict? > AG * > There is no contradiction about what the theories predict because Special Relativity can make no prediction at all about what a clock will do when it is in a gravitational field or is accelerated in any other way; that's why it's called "special", it's only applicable in certain special circumstances. But General Relativity can handle acceleration and gravity. A GPS Satellite is moving fast compared to a clock on the ground so Special Relativity says the clock on the satellite will lose 7210 nanoseconds a day, but the satellite clock is further from the Earth's center so it's in a weaker gravitational field, and because of that general relatively says the satellite clock will gain 45850 nanoseconds a day relative to the clock on the ground. So the two theories together predict the satellite clock will gain 45850 −7210 = 38,640 nanoseconds a day relative to a clock on the ground. If this were not taken into account the GPS system would be in error by 6 miles every day and the error would add up, soon the entire GPS system would be useless. John K Clark -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAJPayv2dYmrvPPTaRA-%2BaL%3DBdcPAOPbzjiS81yN%3DYuwPsiB46A%40mail.gmail.com.
