Metric-affine gravity effects on terrestrial (exo-)planets profiles

TL;DR

This paper investigates how metric-affine gravity, specifically Palatini $f( ext{R})$ models, influences the internal structure of terrestrial planets and proposes seismic data as a new test for gravity theories.

Contribution

It introduces a method to analyze planetary profiles under metric-affine gravity and suggests seismic data as a novel way to test and constrain these gravity models.

Findings

Mass-radius relations for solid materials in planets derived

Degeneracy in planetary profiles discussed within Palatini $f( ext{R})$ gravity

Seismic data proposed as a new test for gravity theories

Abstract

Mass-radius relations of homogeneous cold spheres are obtained for six solid materials commonly found in terrestrial planets. An additional degeneracy in the (exo-)planets' profiles is discussed together with their properties concluded from our findings in the framework of Palatini $f(\mathcal R)$ gravity. Moreover, a new test of gravity has been proposed: The results presented here will allow to test and to constrain models of gravity by the use of seismic data acquired from earthquakes and marsquakes.