The Physics To Go website will be unavailable Friday evening through Saturday afternoon as electrical work occurs in the American Center of Physics server room. Down time will begin at 6PM Eastern Time on Friday. Service is expected to resume by 6PM on Saturday, July 30.

Time Flies Feature Summary

From Physics Research
Time Flies
Einstein's theory of special relativity says that a moving clock, when compared to a stationary clock, runs slow. And general relativity, his theory of gravity, says that the weaker the gravitational field, the faster a clock in that field runs. These predictions were tested in 1971 by flying atomic clocks around the world. Einstein's relativity theories correctly explained what happened.

To learn about a more accurate update to this experiment 25 years later, see Time Flies. Click on the image to see a photo of the atomic clocks in the updated experiment.
image credit: André Karwath, Creative Commons; <a href=" " target="_blank">image source</a>; second image courtesy of <a href="" target="_blank">NPL</a>
image credit: André Karwath, Creative Commons; image source; second image courtesy of NPL
Image URL: clock jet plane.jpg
November 1, 2011 - November 15, 2011