My superficial knowledge of the subject comes from an A in a grad class at Caltech on Relativity, long before GPS. No problem in measuring interval between events at the same place, with a relativistic correction. The issue here is synchronization of clocks at different points in space (CERN and Italy). This is doable, of course, but not trivial. Still hopin' Mr. Natural will enlighten me!
Incidentally, most "explanations" of GPS are vaguely incorrect. You CAN'T directly measure the time a signal takes to get to you, sitting at a mountain lake, from a Teapot in the sky, because you can't synchronize your $199 Gelsons GPS unit. It doan really know when the signal was sent. There's a tricky little calculation involving the difference in arrival time at your station between calibrated signals from two located, synchronized Teapots. It does assume you are at one place at a given instant -- oftentimes the case with me. GPS, like most things in this world, is much smarter than its interpreters! Peter Lissaman, Da Vinci Ventures Expertise is not knowing everything, but knowing what to look for. 1454 Miracerros Loop South, Santa Fe, New Mexico 87505,USA tel:(505)983-7728
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