Word: sadeh
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...When the sun rises, Physicists Dror Sadeh and Benjamin Au report in Nature, the ticking of their test atomic clock mysteriously slows down and then speeds up. Sadeh and Au observed this disconcerting phenomenon after discovering another strange effect: the farther they carried an atomic clock from their laboratory, the slower it seemed to run in relation to a similar clock that was left behind. Pondering the strange "distance effect," they decided to compare the performance of two atomic clocks at separate, fixed locations over an extended period of time. They stationed one clock at Cape Fear, N.C.; their other...
...first, Sadeh and Au were inclined to blame environmental factors. But when they varied the temperatures at both stations, for example, the atomic clocks did not respond in any way. Other checks seemed to eliminate atmospheric irregularities that might have affected the radio waves carrying the time signals between North Carolina and Washington. The experimenters also ruled out a time slowdown that might have been caused by the mass of the sun or moon. Totally baffled, they concluded that they had observed "a new phenomenon which does not have any obvious explanation...
...speed up correspondingly in June, the pulsar signals (which have blipped at a constant frequency since they were discovered) would appear to increase their repetition rates as earth clocks slowed down and decrease them as earth time speeded up. Hoffmann's plan was immediately snapped up by Dror Sadeh, a Tel Aviv University physicist currently attached to the U.S. Naval Research Laboratory at Washington...
Using the Navy's 150-ft. radio telescope at Sugar Grove, W. Va., Dr. Sadeh will attempt this month to establish the pulse rate of one or more of the pulsars to an accuracy of one part in 10 billion-the equivalent of a clock that would gain or lose only 1/300th of a second per year. Then, twice a month for the next half a year, he will match the rate of incoming pulses against a cesium clock, an atomic timer that is accurate to one part in 10 trillion...
...Sadeh feels sure that by January he should be able to detect an apparent speedup in the pulsar clock when compared with its rate this month-a clear indication that earth time has slowed by the same amount. If Einstein was right, that observed slowdown will total about 1/ 100th of a second per year. "If our measurements are accurate and we don't get this result," says Hoffmann, "then we scientists-and the Einstein theory-are in trouble...