Quantum communications and quantum metrology in the spacetime of a rotating planet

TL;DR

This paper investigates how Earth's curved spacetime influences quantum communication and metrology, enabling precise estimation of Earth's parameters through photon wavepacket analysis in satellite-based systems.

Contribution

It introduces a quantum framework for analyzing spacetime effects on photon propagation, enhancing parameter estimation accuracy over classical methods.

Findings

Quantum wavepackets encode Earth's spacetime parameters

Quantum methods outperform classical in parameter estimation

Analysis applicable to satellite-to-satellite quantum communication

Abstract

We study how quantum systems that propagate in the spacetime of a rotating planet are affected by the curved background. Spacetime curvature affects wavepackets of photons propagating from Earth to a satellite, and the changes in the wavepacket encode the parameters of the spacetime. This allows us to evaluate quantitatively how quantum communications are affected by the curved spacetime background of the Earth and to achieve precise measurements of Earth's Schwarzschild radius and equatorial angular velocity. We then provide a comparison with the state of the art in parameter estimation obtained through classical means. Satellite to satellite communications and future directions are also discussed.