UC Berkley announced yesterday the results of the most precise test of Einstein’s Theory of General Relativity ever accomplished. Professor Holger Muller’s experiment confirms Einstein’s prediction that the passage of time is slowed down by gravity. Muller’s measurement matches Einstein’s prediction to better than 1 part in 100 million, which is the limit of the experiment’s precision and is 10,000 more accurate than any prior measurement.
To achieve this extraordinary accuracy, Muller cooled cesium atoms to a few millionth of a degree above absolute zero (-455oF) and “tossed” half of them up 4/1000ths of an inch. In the 1/3 of a second it took the elevated atoms to fall back down, they “aged” 20,000 trillionths of a trillionth of a second more than did their stationary siblings. Muller was able to measure that infinitesimal difference to an astonishing 0.000,1 of a trillionth of a trillionth of a second, using an atom interferometer
Einstein Theory of General Relativity is the foundation of our scientific understanding to the universe, the big bang, and black holes. It is also essential to GPS, the Global Positioning System that many of us have in our cars. If not corrected for the slowing of time due to gravity as Einstein explained, GPS readings would drift by 6 miles per day – if GPS got you home on Monday, you’d be in the next town on Tuesday, and possibly out to sea by Friday.
Find out more about gravity and time on my radio shows "Hey, Einstein, What Time Is It?" and "Gravity and the 3 R's" on my website: www.guidetothecosmos.com.
Muller feels he can do even better, and has already started building a more precise experiment.