Shadow of a rotating braneworld black hole

TL;DR

This paper studies how the shadow of a rotating braneworld black hole is affected by tidal charge and rotation, providing insights into potential observational differences from Kerr black holes.

Contribution

It introduces the impact of tidal charge on black hole shadows in braneworld scenarios, extending previous models of rotating black holes.

Findings

Negative tidal charge enlarges and lessens shadow deformation.

Positive tidal charge reduces shadow size and increases deformation.

Naked singularity cases are also analyzed.

Abstract

We investigate the shadow cast by a rotating braneworld black hole, in the Randall-Sundrum scenario. In addition to the angular momentum, the tidal charge term deforms the shape of the shadow. For a given value of the rotation parameter, the presence of a negative tidal charge enlarges the shadow and reduces its deformation with respect to Kerr spacetime, while for a positive charge, the opposite effect is obtained. We also analyze the case in which the combination of the rotation parameter and the tidal charge results in a naked singularity. We discuss the observational prospects corresponding to the supermassive black hole at the Galactic center.