On 1/13/13 4:36 PM, Koobee Wublee wrote: > Let?s enjoy the following play between Tom and a GPS satellite. > Hopefully, the self-styled physicists would begin to understand why GR > is not necessary in designing the GPS.
Koobee, Work through this resource for an understanding of why relativity is necessary for GPS to work.
> Reminder: Relativity in the Global Positioning System >> http://relativity.livingreviews.org/Articles/lrr-2003-1/ > >> Article Abstract >> >> The Global Positioning System (GPS) uses accurate, stable atomic >> clocks in satellites and on the ground to provide world-wide position >> and time determination. These clocks have gravitational and motional >> frequency shifts which are so large that, without carefully accounting >> for numerous relativistic effects, the system would not work. This >> paper discusses the conceptual basis, founded on special and general >> relativity, for navigation using GPS. Relativistic principles and >> effects which must be considered include the constancy of the speed of >> light, the equivalence principle, the Sagnac effect, time dilation, >> gravitational frequency shifts, and relativity of synchronization. >> Experimental tests of relativity obtained with a GPS receiver aboard >> the TOPEX/POSEIDON satellite will be discussed. Recently frequency >> jumps arising from satellite orbit adjustments have been identified as >> relativistic effects. These will be explained and some interesting >> applications of GPS will be discussed. > > See: > http://relativity.livingreviews.org/Articles/lrr-2003-1/download/lrr-2003-1Color.pdf > > >