Effects of Born-Infeld electrodynamics on black hole shadows

TL;DR

This paper investigates how Born-Infeld nonlinear electrodynamics influences black hole shadows, revealing that magnetic charge enlarges shadows and magnetic fields cause shadow distortion, using ray-tracing simulations.

Contribution

It provides the first detailed analysis of black hole shadows in Born-Infeld electrodynamics, including effects of magnetic monopoles and magnetic fields.

Findings

Shadow radius increases with nonlinear electromagnetic effects.

Magnetic fields cause shadows to stretch along the equatorial plane.

Photon trajectories are affected by BI magnetic fields leading to distinctive shadow shapes.

Abstract

In this work, we study the shadow of Born-Infeld (BI) black holes with magnetic monopoles and Schwarzschild black holes immersed in the BI uniform magnetic field. Illuminated by a celestial sphere, black hole images are obtained by using the backward ray-tracing method. For magnetically charged BI black holes, we find that the shadow radius increases with the increase of nonlinear electromagnetics effects. For Schwarzschild black holes immersed in the BI uniform magnetic field, photons tend to move towards the axis of symmetric, resulting in stretched shadows along the equatorial plane.