Around-the-World Atomic Clocks: Predicted Relativistic Time Gains

  title={Around-the-World Atomic Clocks: Predicted Relativistic Time Gains},
  author={Joseph C. Hafele and Richard E. Keating},
  pages={166 - 168}
During October 1971, four cesium beam atomic clocks were flown on regularly scheduled commercial jet flights around the world twice, once eastward and once westward, to test Einstein's theory of relativity with macroscopic clocks. From the actual flight paths of each trip, the theory predicts that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40 � 23 nanoseconds during the eastward trip, and should have gained 275 � 21 nanoseconds during the… 

Around-the-World Atomic Clocks: Observed Relativistic Time Gains

Four cesium beam clocks flown around the world on commercial jet flights during October 1971, once eastward and once westward, recorded directionally dependent time differences which are in good

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In his communication1 on the relativistic behaviour of moving terrestrial clocks Hafele deduces that an airborne clock, after circumnavigating the Earth, could be either fast or slow when compared

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. Atomic clock accuracies continue to improve rapidly, requir­ ing the inclusion of general relativity for unambiguous time and fre­ quency clock comparisons. Atomic clocks are now placed on space

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  • 1971

Radiation exposure in air travel.

Relativistic Behaviour of Moving Terrestrial Clocks

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How scientists can really help

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Metrologia 1 (No

  • L. N. Bodily and R. C. Hyatt. Hewlett-Packard J. 19,
  • 1967

This book gives an excellent historical review of debate on the clock paradox and serves well as an introduction to relativity theory

  • Titme and the Space-Traveller
  • 1971

It is important to emphasize that special