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arXiv · 1409.0234

Quantum estimation of the Schwarzschild space-time parameters of the Earth

David Edward Bruschi·Animesh Datta·Rupert Ursin·Timothy C. Ralph·Ivette Fuentes
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Abstract

We propose a quantum experiment to measure with high precision the Schwarzschild space-time parameters of the Earth. The scheme can also be applied to measure distances by taking into account the curvature of the Earth's space-time. As a wave-packet of (entangled) light is sent from the Earth to a satellite it is red-shifted and deformed due to the curvature of space-time. Measurements after the propagation enable the estimation of the space-time parameters. We compare our results with the state of the art, which involves classical measurement methods, and discuss what developments are required in space-based quantum experiments to improve on the current measurement of the Schwarzschild radius of the Earth.

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David Edward Bruschi, Animesh Datta, Rupert Ursin, Timothy C. Ralph, Ivette Fuentes. 2014-08-31. Quantum estimation of the Schwarzschild space-time parameters of the Earth. https://doi.org/10.1103/physrevd.90.124001

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