Regular black hole metrics and the weak energy condition

In this work we construct a family of spherically symmetric, static, charged regular black hole metrics in the context of Einstein-nonlinear electrodynamics theory. The construction of the charged regular black hole metrics is based on three requirements: (a) the weak energy condition should be satisfied, (b) the energy-momentum tensor should have the symmetry $T^{0}_{0}=T^{1}_{1}$, and (c) these metrics have to asymptotically behave as the Reissner-Nordstr\"{o}m black hole metric. In addition, these charged regular black hole metrics depend on two parameters which for specific values yield regular black hole metrics that already exist in the literature. Furthermore, by relaxing the third requirement, we construct more general regular black hole metrics which do not behave asymptotically as a Reissner-Nordstr\"{o}m black hole metric.Comment: v1: 11 pages, LaTeX, no figures; v2: typos corrected and one reference removed to match published version in Phys. Lett.

Quasilocal energy, Komar charge and horizon for regular black holes

We study the Brown-York quasilocal energy for regular black holes. We also express the identity that relates the difference of the Brown-York quasilocal energy and the Komar charge at the horizon to the total energy of the spacetime for static and spherically symmetric black hole solutions in a convenient way which permits us to understand why this identity is not satisfied when we consider nonlinear electrodynamics. However, we give a relation between quantities evaluated at the horizon and at infinity when nonlinear electrodynamics is considered. Similar relations are obtained for more general static and spherically symmetric black hole solutions which include solutions of dilaton gravity theories.Facultad de Ciencias Exacta

Quasilocal energy, Komar charge and horizon for regular black holes

We study the Brown-York quasilocal energy for regular black holes. We also express the identity that relates the difference of the Brown-York quasilocal energy and the Komar charge at the horizon to the total energy of the spacetime for static and spherically symmetric black hole solutions in a convenient way which permits us to understand why this identity is not satisfied when we consider nonlinear electrodynamics. However, we give a relation between quantities evaluated at the horizon and at infinity when nonlinear electrodynamics is considered. Similar relations are obtained for more general static and spherically symmetric black hole solutions which include solutions of dilaton gravity theories.Facultad de Ciencias Exacta

Thermodynamics and the Joule-Thomson expansion of dilaton black holes in 2+1 dimensions

In this paper, we study thermodynamics and its applications to the static charged dilaton black hole in 2+1 dimensions. We compute the first law and the Smarr relations for the black hole and introduce a new thermodynamical parameter in order to satisfy the first law. We compute specific heat capacities, internal energy and free energy for the black hole and study local and global stability of the black hole. For N = 1, the black hole is locally stable for all values of the horizon radius and does not go through phase transitions. Maxwell`s relations are presented for this case. For N = 6/7, small black holes are locally stable and large black holes are not. There is a first order phase transition between small black holes and the thermal AdS space. We have also studied the Joule-Thomson expansion for black holes with N = 1. It is also noted that unlike the charged BTZ black hole, the charged dilaton black hole does not violate the Reverse Isoperimetric Inequality for certain values of parameters of the theory.Comment: 26 pages, 12 figure

Regular charged black holes, energy conditions and quasinormal modes

We discuss energy conditions and quasinormal modes for scalar perturbations of regular charged black holes within the framework of General Relativity coupled to non-linear electrodynamics. The frequencies are computed numerically adopting the WKB method, while in the eikonal limit an analytic expression for the spectra is obtained. The impact of the electric charge, the angular degree, and the overtone number on the spectra is investigated in detail. We find that all frequencies are characterized by a negative imaginary part, and that each type of energy conditions imply a different quasinormal spectrum.Comment: 29 pages, 11 figures, 5 tables, to be published in Fortschritte der Physi