Papers by Leonardo Amarilla
arXiv: General Relativity and Quantum Cosmology, 2015
We examine the shadow of a rotating Kaluza-Klein black hole in Einstein gravity coupled to a Maxw... more We examine the shadow of a rotating Kaluza-Klein black hole in Einstein gravity coupled to a Maxwell field and a dilaton. The size and the shape of the shadow depend on the mass, the charge, and the angular momentum of the compact object. For a given mass, the size increases with the rotation parameter and decreases with the electric charge. The distortion with respect to the non rotating case grows with the charge and the rotation parameter. For fixed values of these parameters, the shadow is slightly larger and less deformed than in the Kerr-Newman case. The study of gravitational lensing by black holes has received great attention in the last decade, due to the evidence of the presence of supermassive compact objects at the galactic centers. The apparent shapes (or shadows) of non-rotating black holes are circular, but rotating ones present a deformation produced by the spin; topic recently investigated by several researchers, both in Einstein gravity and in modified theories, wi...
Physical Review D, 2012
We investigate the shadow cast by a rotating braneworld black hole, in the Randall-Sundrum scenar... more 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.
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Papers by Leonardo Amarilla