That effectively means, for a few hundred bucks, Williams can turn it into an atomic clock that he could slip into his pocket.
Inside, Williams explains, is a receiver tailored to make use of a signal from an atomic clock carried by a global positioning system satellite.
When Jerrold Zacharias was developing the first atomic clock, working in Building 20, he removed two floors in his lab to make room for a three-story metal cylinder.
One example of which the White House is fond is the atomic clock the Pentagon helped Harvard to develop so that scientists could test Einstein's theory of relativity.
Over a five-year period, the satellite's e2v array, allied to two telescopes and some sophisticated instrumentation that includes an atomic clock, will make an unprecedented 3D map of our Milky Way Galaxy.
That famous atomic clock, after all, may first have sprung from nothing more than intellectual curiosity, but it must also have occurred to the Pentagon that precise measurement might have some military use.
Unless Apple was using an atomic clock to measure the exact nanosecond of purchase, it is perhaps fair to say that their choice of Chunli Fu, from Qingtao, China, a week ago, was highly intentional.
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"The atomic clock is actually putting out an electronic signal which is essentially analogous to the ticking of a pendulum clock... which might tick once every second or once every couple of seconds, " says Dr McCarthy.
Over a few decades this would amount to a minute's difference, but over several hundred years this would mean the atomic clock time-scale and the time-scale based on the Earth's rotation would be out by an hour.
Jerrold Zacharias at the Massachusetts Institute of Technology developed a practical atomic clock around the same time that Louis Essen and John Parry established the first atomic clock at the National Physical Laboratory in Teddington, west of London.
Equipped with a bar-code reader to scan New York registration stickers and synchronized with an atomic clock in Colorado, the devices make it almost impossible for an agent to make the kinds of errors Bolofsky depends on for appeals.
Since it gets its time from the GPS satellites, all of which contain on-board atomic clocks, if your watch stops you'll always have an accurate clock handy.
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