Determination of the difference in gravitational potentials in the Earth's field based on the measurement of the gravitational delay of light waves in an optical fiber

Abstract. The possibility of determining the difference in gravitational potentials and optometric heights in the Earth's field based on measurements of the phase difference of laser radiation in an optical fiber, due to the effect of the gravitational delay of light waves, is proposed and investigated. A block diagram of a measuring complex designed to measure the phase difference of light waves caused by this effect is proposed. The measurements use two coherent light waves from a single laser, each propagating along a separate fiber optic communication line. The composition of each fiber-optic communication line includes the same coils of a long optical fi beer, spaced apart in height. The analysis of the factors info fencing the phase relations of waves propagating along two communication lines of the measuring complex is carried out. The phase effects of the delay caused by the influence of the true gravitational field of the Earth, as well as the info hence of the fields of inertial forces and gyroscopic effects due to the rotation of the Earth are determined. Ways to suppress the effects that introduce measurement errors are proposed. The achievable errors in measuring the diff Terence in gravitational potentials and the corresponding diff Terence in optometric heights are estimated. With a fi err length in coils of 100 km and a height diff Terence of 100 m; these errors are 0.2 m2/s2 and 2 cm, respectively. It is proposed to call the measuring complex under study a laser gravipotentiometer. It is an optical analogue of the well-known radio-frequency quantum level, but does not require ultra-stable frequency and time standards. The research results of the proposed measuring complex are relevant for the development and improvement of measuring instruments for the parameters of the Earth's gravitational fi eld, as well as means of high-precision synchronization of time scales of remote standards.

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