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arXiv · 2308.01784

Earthquakes as probing tools for gravity theories

Aleksander Kozak·Aneta Wojnar
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Abstract

We propose a novel method for testing gravity models using seismic data from Earth. By imposing observational constraints on Earth's moment of inertia and mass, we rigorously limit the gravitational models' parameters within a $2σ$ accuracy. Our method constrains the parameters governing additional terms to the General Relativity Lagrangian to the following ranges: $-2\times10^9\lesssimβ\lesssim 10^9 \text{m}^2$ for Palatini $f(R)$ gravity, $-8\times10^9\lesssimε\lesssim 4\times 10^9 \text{m}^2$ for Eddington-inspired Born-Infeld gravity, and $-10^{-3}\lesssimΥ\lesssim10^{-3}$ for Degenerate Higher-Order Scalar-Tensor theories. We also discuss potential avenues to enhance the proposed method, aiming to impose even tighter constraints on gravity models.

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Aleksander Kozak, Aneta Wojnar. 2023-08-03. Earthquakes as probing tools for gravity theories. https://arxiv.org/abs/2308.01784

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