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arXiv · 2010.15870

Black Hole Shadows in Verlinde's Emergent Gravity

Kimet Jusufi·Saurabh
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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.

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Kimet Jusufi, Saurabh. 2020-10-23. Black Hole Shadows in Verlinde's Emergent Gravity. https://doi.org/10.1093/mnras/stab476

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