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arXiv · 0904.1338

Static and Radiating Solutions of Lovelock Gravity in the Presence of a Perfect Fluid

M. H. Dehghani·N. Farhangkhah
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Abstract

We present a general solution of third order Lovelock gravity in the presence of a specific type II perfect fluid. This solution for linear equation of state, $p=w(ρ-4B)$ contains all the known solutions of third order Lovelock gravity in the literature and some new static and radiating solutions for different values of $w$ and $B$. Specially, we consider the properties of static and radiating solutions for $w=0$ and $w=(n-2)^{-1}$ with B=0 and $B\neq0$. These solutions are asymptotically flat for B=0, while they are asymptotically (anti)-de Sitter for $B\neq0$. The new static solutions for these choices of $B$ and $w$ present black holes with one or two horizons, extreme black holes or naked singularities provided the parameters of the solutions are chosen suitable. The static solution with $w=0$ and vanishing geometrical mass ($m=0$) may present a black hole with two inner and outer horizons. This is a peculiar feature of the third order Lovelock gravity, which does not occur in lower order Lovelock gravity. We also, investigate the properties of radiating solutions for these values of $B$ and $w$, and compare the singularity strengths of them with the known radiating solutions of third order Lovelock gravity.

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BibTeXRIS

M. H. Dehghani, N. Farhangkhah. 2009-04-08. Static and Radiating Solutions of Lovelock Gravity in the Presence of a Perfect Fluid. https://doi.org/10.1016/j.physletb.2009.03.045

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