Deflection of light by a Coulomb charge in Born-Infeld electrodynamics

TL;DR

This paper investigates how strong electric fields in Born-Infeld electrodynamics influence light propagation, demonstrating that non-uniform backgrounds cause light bending, with calculations for Coulomb charges and black holes confirming the effect.

Contribution

It provides the first detailed calculation of light deflection in Born-Infeld electrodynamics for Coulomb charges and black holes, linking nonlinear electromagnetic effects to gravitational lensing.

Findings

Light bending depends on background electric field strength.

Deflection angles for Coulomb charge and black hole agree.

Nonlinear electrodynamics affects optical trajectories.

Abstract

We study the propagation of light under a strong electric field in Born-Infeld electrrdynamics. The nonlinear effect can be described by the effective indices of refraction. Because the effective indices of refraction depend on the background electric field, the path of light can be bent when the background field is non-uniform. We compute the bending angle of light by a Born-Infeld-type Coulomb charge in the weak lensing limit using the trajectory equation based on geometric optics. We also compute the deflection angle of light by the Einstein-Born-Infeld black hole using the geodesic equation and confirm that the contribution of the electric charge to the total bending angle agree.