Would've been more fun to see Tom and his kids going to the top of Mt Ranier in 2005 with the ensemble :-). http://leapsecond.com/great2005/
They mentioned some "6 miles per day" offset due to GPS relativity effects. I think this is the sum of both special relativity (time dilation) and general relativity (gravitational) effects. The GR correction is 45 microseconds a day fast; the SR correction is 7 microseconds slow. 38 microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While time drifts 38 microseconds a day, I'm not sure that GPS coordinates would drift that fast - aren't most of the corrections in the same direction? Seeing Kip Thorne describe black holes was a blast - he refused to use the word mass when describing them, just like when I took a course from him in 1990. When my advisor taught the same course, I pleaded with him, "please use coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my brain does not work that way!!! I would've failed the course if it was only GR; fortunately it also had plasma physics in the same quarter, and I was an ace at that due to some undergraduate work.) Tim N3QE On Fri, Nov 27, 2015 at 12:05 AM, Arthur Dent <[email protected]> wrote: > In the special it looks like they used two HP5071A standards, an > SRS620 counter, and a scope. They first made sure the stds were > in sync then took one to the building at the top of the ski lift > on New Hampshire's Mount Sunapee at 2726' elevation for 4 days > where it would be running a little faster because it would be > slightly further from the center of the spinning earth. After > bringing the 5071A back from the top of the mountain they checked > the difference in the start of square waves displayed on the scope > and detected the 5071A at altitude was now 20ns ahead of the > 5071A kept at sea level, as predicted, if I understood everything > correctly. They explained that the clocks in the GPS satellites > traveling at a much higher speed had to correct for the speed > difference which also verified Einstein's theory. > > My wife and I were on the top of Mt. Sunapee this summer where we > enjoyed the views but didn't run any experiments. ;-) > > -Arthur > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
