English

Kerr-Anti-De-Sitter/De-Sitter Black Hole In Perfect Fluid Dark Matter Background

General Relativity and Quantum Cosmology 2018-04-24 v2

Abstract

We obtain the Kerr-anti-de-sitter (Kerr-AdS) and Kerr-de-sitter (Kerr-dS) black hole (BH) solutions to the Einstein field equation in the perfect fluid dark matter background using the Newman-Janis method and Mathematica package. We discuss in detail the black hole properties and obtain the following main results: (i) From the horizon equation grr=0g_{rr}=0, we derive the relation between the perfect fluid dark matter parameter α\alpha and the cosmological constant Λ\Lambda when the cosmological horizon rΛr_{\Lambda} exists. For Λ=0\Lambda=0, we find that α\alpha is in the range 0<α<2M0<\alpha<2M for α>0\alpha>0 and 7.18M<α<0-7.18M<\alpha<0 for α<0\alpha<0. For positive cosmological constant Λ\Lambda (Kerr-AdS BH), αmax\alpha_{max} decreases if α>0\alpha>0, and αmin\alpha_{min} increases if α<0\alpha<0. For negative cosmological constant Λ-\Lambda (Kerr-dS BH), αmax\alpha_{max} increases if α>0\alpha>0 and αmin\alpha_{min} decreases if α<0\alpha<0; (ii) An ergosphere exists between the event horizon and the outer static limit surface. The size of the ergosphere evolves oppositely for α>0\alpha>0 and α<0\alpha<0, while decreasing with the increasing α\mid\alpha\mid. When there is sufficient dark matter around the black hole, the black hole spacetime changes remarkably; (iii) The singularity of these black holes is the same as that of rotational black holes. In addition, we study the geodesic motion using the Hamilton-Jacobi formalism and find that when α\alpha is in the above ranges for Λ=0\Lambda=0, stable orbits exist. Furthermore, the rotational velocity of the black hole in the equatorial plane has different behaviour for different α\alpha and the black hole spin aa. It is asymptotically flat and independent of α\alpha if α>0\alpha>0 while is asymptotically flat only when α\alpha is close to zero if α<0\alpha<0.

Keywords

Cite

@article{arxiv.1711.04538,
  title  = {Kerr-Anti-De-Sitter/De-Sitter Black Hole In Perfect Fluid Dark Matter Background},
  author = {Zhaoyi Xu and Xian Hou and Jiancheng Wang},
  journal= {arXiv preprint arXiv:1711.04538},
  year   = {2018}
}

Comments

22 pages, 4 figures