相关论文: Properties of Bigravity Solutions in a Solvable Cl…
We present a class of exact analytic and static, spherically symmetric black hole solutions in the semi-classical Einstein equations with Weyl anomaly. The solutions have two branches, one is asymptotically flat and the other asymptotically…
We find static spherically symmetric solutions of scale invariant $R^2$ gravity. The latter has been shown to be equivalent to General Relativity with a positive cosmological constant and a scalar mode. Therefore, one expects that solutions…
In this paper we review the properties of the black hole entropy in the light of a general conformal field theory treatment. We find that the properties of horizons of the BTZ black holes in ADS_{3}, can be described in terms of an…
Regarding a special class of pure F(R) gravity in three dimensions, we obtain, analytically, Lifshitz-like black hole solutions. We check the geometrical properties of the solutions which behave such as charged BTZ black holes in special…
We consider N=2 supergravity in four dimensions with small R^2 curvature corrections. We construct large charge non-extremal black hole solutions in all space, with either a supersymmetric or a non-supersymmetric extremal limit, and analyze…
Different theories of gravity can admit the same black hole solution, but the parameters usually have different physical interpretations. In this work we study in depth the linear term $\beta r$ in the redshift function of black holes,…
Einstein gravity at $D\rightarrow 2$ limit can be obtained from the Kaluza-Klein procedure by taking the dimensions of the internal space to zero while keeping only the breathing mode. The resulting scalar-tensor theory can be further…
We obtain and analyze an exact solution to Einstein-Maxwell-scalar theory in $(2+1)$ dimensions, in which the scalar field couples to gravity in a non-minimal way, and it also couples to itself with the self-interacting potential solely…
We consider the physical properties of four dimensional black hole solutions to the effective action describing the low energy dynamics of the gravitational sector of heterotic superstring theory. We compare the properties of the external…
In this paper, we investigate regular black hole solutions in the (2+1)-dimensional versions of General Relativity and $f(R, T)$ gravity, both coupled to nonlinear electrodynamics. By admitting that the matter content that generates such…
By making use of the entropy function formalism we study the generalized attractor equations in the four dimensional N=2 supergravity in presence of higher order corrections. This result might be used to understand a possible ensemble one…
We argue that the Isham-Storey exact solution to bigravity does not describe black holes because the horizon is a singular surface. However, this is not a generic property of bigravity, but a property of a particular potential. More general…
We derive a general local form for supersymmetric solutions of six-dimensional (1,0) supergravity coupled to an arbitrary number of tensor multiplets. We consider some special cases in which the resulting equations can be solved explicitly.…
Novel static black hole solutions with electric and magnetic charges are derived for the class of modified gravities: $f({\cal R})={\cal R}+2\beta\sqrt{{\cal R}}$, with or without a cosmological constant. The new black holes behave…
We establish a framework to construct spherically symmetric and static solutions in $f(R)$ gravity coupled with nonlinear electromagnetic fields. We present two new specific solutions and discuss the energy conditions. We calculate some…
We present an exact black hole solution in a model having besides gravity a dilaton and a monopole field, which is a generalization of a black hole solution we have found. The new solution, as the previous one, has three free parameters,…
We study the generalization of the Ansatz of Galli et al. for non-extremal black holes of N=2,d=4 supergravities for a simple model of N=2,d=5 supergravity with a vector multiplet whose moduli space has two branches. We use the formalism of…
The five dimensional Einstein-Gauss-Bonnet gravity with a negative cosmological constant becomes, for a special value of the Gauss-Bonnet coupling constant, a Chern-Simons (CS) theory of gravity. In this work we discuss the properties of…
The nonlinear Maxwell Lagrangian preserving both conformal and SO(2) duality-rotation invariance has been introduced very recently. Here, in the context of Einstein's theory of gravity minimally coupled with this nonlinear electrodynamics,…
We find the topological entropy formula for all $N>2$ extended supergravities in five dimensions and the fixed scalar condition for the black-hole ``potential energy'' which extremizes the BPS mass. We comment upon the interpretation of…