Optical Clocks and Relativity

  title={Optical Clocks and Relativity},
  author={Chin-wen Chou and David B. Hume and Till Rosenband and David J. Wineland},
  pages={1630 - 1633}
Relativity Comes Down to Earth Over a century ago, Einstein presented the theory of relativity—where space and time are no longer fixed concepts, but are relative to an observer and their frame of reference. Tests of relativity have usually been confined to space-based measurements and/or with objects with velocities approaching the speed of light. Time-dilation and length-contraction have been confirmed and are used in satellite communication and global positioning systems. Using the precision… 

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