Dynamics of galaxies and clusters in \textit{refracted gravity}

TL;DR

Refracted gravity is a new modified gravity theory that adjusts gravitational behavior based on local density, successfully explaining galaxy rotation curves, the Tully-Fisher relation, and galaxy cluster temperature profiles without dark matter.

Contribution

This paper introduces refracted gravity, a novel modified gravity model inspired by electric field behavior, to explain cosmic structures without dark matter.

Findings

Reproduces galaxy rotation curves and Tully-Fisher relation.

Matches observed temperature profiles of galaxy cluster gas.

Provides a viable alternative to dark matter in cosmic structure dynamics.

Abstract

We investigate the proof of concept and the implications of \textit{refracted gravity}, a novel modified gravity aimed to solve the discrepancy between the luminous and the dynamical mass of cosmic structures without resorting to dark matter. Inspired by the behavior of electric fields in matter, refracted gravity introduces a gravitational permittivity that depends on the local mass density and modifies the standard Poisson equation. The resulting gravitational field can become more intense than the Newtonian field and can mimic the presence of dark matter. We show that the refracted gravitational field correctly describes (1) the rotation curves and the Tully-Fisher relation of disk galaxies; and (2) the observed temperature profile of the X-ray gas of galaxy clusters. According to these promising results, we conclude that refracted gravity deserves further investigation.