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Earth-based clocks test general relativity

Optical clocks held at slightly different heights provide a stringent test of general relativity comparable to space experiments and open new opportunities for clock-based geophysical sensing.

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Fig. 1: Illustration of how in the future relativistic geodesy might be done with clocks.


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Correspondence to Kai Bongs.

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Bongs, K., Singh, Y. Earth-based clocks test general relativity. Nat. Photonics 14, 408–409 (2020).

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