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In the present paper, a new class of black hole solutions is constructed in even dimensional Lovelock Born-Infeld theory. These solutions are interesting since, in some respects, they are closer to black hole solutions of an odd dimensional Lovelock Chern-Simons theory than to the more usual black hole solutions in even dimensions. This hybrid behavior arises when non-Einstein base manifolds are considered. The entropies of these solutions have been analyzed using Wald formalism. These metrics exhibit a quite non-trivial behavior. Their entropies can change sign and can even be identically zero depending on the geometry of the corresponding base manifolds. Therefore, the request of thermodynamical stability constrains the geometry of the non-Einstein base manifolds. It will be shown that some of these solutions can support non-vanishing torsion. Eventually, the possibility to define a sort of topological charge associated with torsion will be discussed.
We obtain rotating black hole solutions to the novel 3D Gauss-Bonnet theory of gravity recently proposed. These solutions generalize the BTZ metric and are not of constant curvature. They possess an ergoregion and outer horizon, but do not have an in
Recent studies have presented the interpretation of thermodynamic enthalpy for the mass of BTZ black holes and the corresponding Smarr formula. All these are made in the background of three-dimensional (3D) general relativity. In this paper, we exten
Here we have developed the general parametrization for spherically symmetric and asymptotically flat black-hole spacetimes in an arbitrary metric theory of gravity. The parametrization is similar in spirit to the parametrized post-Newtonian (PPN) app
It is found that, when the coupling constants $alpha_p$ in the theory of regularized Lovelock gravity are properly chosen and the number of Lovelock tensors $prightarrow infty$, there exist a fairly large number of nonsingular (singularity free) blac
In order to classify and understand the spacetime structure, investigation of the geodesic motion of massive and massless particles is a key tool. So the geodesic equation is a central equation of gravitating systems and the subject of geodesics in t