Atomic clock performance enabling geodesy below the. Pdf test of relativistic time dilation with fast optical atomic clocks. Time, frequency and the atomic clock, claude audoin and bernard guinot translated from french by stephen lyle cambridge u. It is possible to observe the combined effect of general and special relativity on an atomic clock on board a gps satellite. New tests of special and general relativity using atomic clocks on the ground and in space. Relativistic effects on satellite clock as seen from earth. The year 2005 was the 100th anniversary of einsteins first paper on relativity. Further potential applications of highly precise atomic clocks. Atomic clocks make best measurement yet of relativity of. Practical realization of the definition of the unit of time.
Time dilation is a difference in the elapsed time measured by two clocks, either due to them having a velocity relative to each other, or by there being a gravitational potential difference between their locations. Einstein first predicted in his general theory of relativity that gravity alters time, an effect sometimes called the gravitational redshift. Introducing relativity in global navigation satellite systems. Practical realization of the definition of the unit of. The system is based on an array of 24 satellites orbiting the earth, each carrying a precise atomic clock. The hafelekeating experiment was a test of the theory of relativity. Atomic clocks can also be used to measure changes in the gravitational field on earth. Doppler effect, the observer will measure the moving clock as. Pdf time dilation is one of the most fascinating aspects of special relativity as it abolishes the notion of absolute time. One of the actual hp 5061a cesium beam atomic clock units used in the hafelekeating experiment.
Any violation of this principle could point us to a longsought theory that would unite einsteins ideas with quantum mechanics. It was also the 50th anniversary of essens first cesium atomic clock. The special theory of relativity predicts time dilation. General relativity vasily yanchilin the paper was published in the journal world of measurements, december 2010 russian simple analysis of atom behavior in gravitational field reveals. Valls hidalgogato 1 natalio svarch scharager 2 abstract. During october 1971, four cosium beam atomic clocks were flown on regularly scheduled commercial jet flights around the world twice, once east ward and once westward, to test einsteins theory of relativity with macroscopic clocks. Thus, for each atomic clock, the gps generates a paper clock that reads t. Accurate to a second in 300 million years the clocks will push the measurement of time to test the limits of the theory of relativity and our understanding of gravity. A clock on a fastflying satellite appears to run slower when observed from a stationary position on earth. Enrico mai time, atomic clocks, and relativistic geodesy. Time, frequency and the atomic clock claude audoin and bernard guinot frontmatter more information.
New tests of special and general relativity using atomic clocks on the. All coordinate clocks generated in this way would be selfconsistently synchronized ifone brought them togetherassuming that general relativity is cor rect. That, in essence, is the procedure used in the gps. Atomic clocks make best measurement yet of relativity of time our most accurate clocks are probing a key tenet of einsteins theory of relativity. Project great general relativity einsteinessen anniversary test was conceived to celebrate both events in a single experiment. After compensating for varying signal delays due to the changing distance between an observer and a moving clock i. According to general relativity, the ticking rate of a clock depends on its. Relative to a given observer, time and the devices that measure time clocks is seen to evolve more slowly deeper in a gravity potential. Explaining atomic clock behavior in a gravitational field. Then we compared the time they recorded dur ing each trip with the corresponding time recorded by the reference atomic time scale at the u.