The Galactic Halo Rotation by Weyl Incorporated Gravity

TL;DR

This paper explores a modified gravity theory involving Weyl tensor coupling to explain galactic rotation curves without dark matter, applying it to multiple galaxies with realistic density profiles.

Contribution

It extends previous models by incorporating variable density profiles and applies the formalism to real galaxies, including the Milky Way.

Findings

Successfully modeled galactic rotation curves without dark matter.

Determined a consistent coupling constant across different galaxies.

Applied the model to seven local cluster galaxies and the Milky Way.

Abstract

A modification of the Einstein-Hilbert Lagrangian by introducing a coupling between the Weyl tensor and the stress-energy tensor was proposed to explain flat galactic rotation curves without the exotic (non-baryonic) dark matter (DM) [1]. The proposed coupling constant was previously determined by fitting the rotational velocities of the Milky Way and M31 modeled with constant density, yielding the same coupling constant for both [2,3]. In this work, we have modified the formalism for a variable density by modeling the galactic systems with realistic, spherically symmetric and radially varying density profiles for the baryonic matter and this analysis is applied to seven edge-on spiral galaxies of the local cluster [4-10] and the Milky Way.