The bending of light and lensing in modified gravity

TL;DR

This paper derives equations for light bending and lensing in a modified gravity theory, providing tools to analyze gravitational lensing phenomena without dark matter and supporting previous astrophysical observations.

Contribution

It introduces relativistic equations for light bending in MOG, enabling analysis of lensing effects in various astrophysical contexts without dark matter.

Findings

Derived equations for light bending in MOG

Validated MOG against Bullet Cluster observations

Applied equations to merging galaxy clusters

Abstract

Our modified gravity theory (MOG) was used successfully in the past to explain a range of astronomical and cosmological observations, including galaxy rotation curves, the CMB acoustic peaks, and the galaxy mass power spectrum. MOG was also used successfully to explain the unusual features of the Bullet Cluster 1E0657-558 without exotic dark matter. In the present work, we derive the relativistic equations of motion in the spherically symmetric field of a point source in MOG and, in particular, we derive equations for light bending and lensing. Our results also have broader applications in the case of extended distributions of matter, and they can be used to validate the Bullet Cluster results and provide a possible explanation for the merging clusters in Abell 520.