English

Shapes of rotating nonsingular black hole shadows

General Relativity and Quantum Cosmology 2016-08-03 v2

Abstract

It is believed that curvature singularities are a creation of general relativity and hence, in the absence of a quantum gravity, models of nonsingular black holes have received significant attention. We study the shadow (apparent shape), an optical appearance because of its strong gravitational field, cast by a nonsingular black hole which is characterized by three parameters, i.e., mass (MM), spin (aa), and a deviation parameter (kk). The nonsingular black hole under consideration, is a generalization of the Kerr black hole {that} can be recognized asymptotically (r>>k,k>0r>>k, k>0) explicitly as the Kerr-Newman black hole, and in the limit k0k \rightarrow 0 as the Kerr black hole. It turns out that the shadow of a nonsingular black hole is a dark zone covered by {a} deformed circle. Interestingly, it is seen that the shadow of a black hole is affected due to the parameter kk. Indeed, for a given aa, the size of a shadow reduces as the parameter kk increases and the shadow becomes more distorted as we increase the value of the parameter kk when compared with the analogous Kerr black hole shadow. We also investigate, in detail, how the ergoregion of a black hole is changed due to the deviation parameter kk.

Keywords

Cite

@article{arxiv.1603.06382,
  title  = {Shapes of rotating nonsingular black hole shadows},
  author = {Muhammed Amir and Sushant G. Ghosh},
  journal= {arXiv preprint arXiv:1603.06382},
  year   = {2016}
}

Comments

11 pages, 11 figures, Published version