Black Hole Shadows in Verlinde's Emergent Gravity

TL;DR

This paper investigates how baryonic and apparent dark matter influence black hole shadows within Verlinde's Emergent Gravity, revealing that surrounding matter modestly affects shadow size and intensity, with significant effects at higher baryonic densities.

Contribution

It introduces models of baryonic mass profiles in Verlinde's theory to analyze their impact on black hole shadows and electromagnetic flux, highlighting similarities with standard dark matter effects.

Findings

Surrounding matter slightly alters shadow size with observational data.

Increased baryonic matter significantly impacts shadow and flux.

Power law models mimic isothermal dark matter profiles in Verlinde's framework.

Abstract

We study the effect of baryonic matter and apparent dark matter on black hole shadow in Verlinde's Emergent Gravity. To do so, we consider different baryonic mass profiles and an optically-thin disk region described by a gas in a radial free fall around the black hole. Assuming that most of the baryonic matter in the galaxy is located near the galactic center surrounding a supermassive black hole, we use two models of power law mass profile for the baryonic matter to study the effect of apparent dark matter on the shadow and the corresponding intensity. We find that the effect of the surrounding matter on the shadow size using observational values is small, however, it becomes significant when the surrounding baryonic matter increases. To this end, we show that the effect of simple power law function in the limit of constant baryonic mass in Verlinde's theory implies an apparent dark matter effect which is similar to the standard gravity having an isothermal dark matter profile. We also find the intensity of the electromagnetic flux radiation depending on the surrounding mass.