Measurement of the difference in the Earth’s gravitational potentials with the help of a transportable quantum clock

The results of the Russia’s first ground-based experiment for determination of the difference in the Earth’s gravitational potentials on the basis of the measurement of the gravitational effect of the time delay with the help of a high-stability transportable atomic clock are provided. The reference atomic clock was placed in Moscow oblast, and a transportable quantum clock with an instability of 3 × 10 –15 was placed in the Caucasus Mountains, with a difference in height of the clocks of 1804 m. The measured difference in the gravitational potentials between the positions of the two quantum clocks was (182.0 ± 3.1)10 2 m 2 s -2 at a relative measurement error of no more than 1.7%.