Related papers: Dilatonic Black Holes in Higher Curvature String G…
We study linear perturbations about non rotating black hole solutions in scalar-tensor theories, more specifically Horndeski theories. We consider two particular theories that admit known hairy black hole solutions. The first one,…
We consider a general Einstein-scalar-GB theory with a coupling function f(\phi). We demonstrate that black-hole solutions appear as a generic feature of this theory since a regular horizon and an asymptotically-flat solution may be easily…
Nonrotating and rotating black hole soltuions in (2+1) dimensions are studied in a model including a real scalar field with a simple potential coupled to gravity.
We examine the higher dimensional action in which gravity is coupled to the exponential nonlinear electrodynamic and a scalar dilaton field. We construct a new class of $n$-dimensional static and spherically symmetric black hole solutions…
We discuss with a rather critical eye the current situation of black hole (BH) solutions in $f(R)$ gravity and shed light about its geometrical and physical significance. We also argue about the meaning, existence or lack thereof of a…
Speculation that the fine-structure constant $\alpha$ varies in spacetime has a long history. We derive, in 4-D general relativity and in isotropic coordinates, the solution for a charged spherical black hole according to the framework for…
We present spherically symmetric black hole solutions for Einstein gravity coupled to anisotropic matter. We show that these black holes have arbitrarily short hair, and argue for stability by showing that they can arise from dynamical…
In the framework of a simple gravitational theory that contains a scalar field minimally coupled to gravity, we investigate the emergence of analytic black-hole solutions with non-trivial scalar hair of secondary type. Although it is…
One-loop renormalised quantum effective action for gravity contains quadratic in curvature terms. We have found an approximate analytic black hole solution in quadratic gravity by keeping only the radial spherically symmetric fluctuations…
We study a simple theory based on general relativity, minimally coupled to a constrained scalar triplet and to an auxiliary non-propagating three-form sector. Within a spherically symmetric hedgehog ansatz, the theory admits a continuous…
We show that four-dimensional Einstein-Maxwell-Dilaton-Gauss-Bonnet gravity admits asymptotically flat black hole solutions with a degenerate event horizon of the Reissner-Nordstr\"om type $AdS_2\times S^2$. Such black holes exist for the…
We investigate the possibility of dressing a four-dimensional black hole with classical scalar field hair which is non-minimally coupled to the space-time curvature. Our model includes a cosmological constant but no self-interaction…
It has been shown recently that there is a large class of supersymmetric solutions of five-dimensional supergravity which generalize the supersymmetric black ring solution of Elvang et al. This class involves arbitrary functions. We show…
We find analytic solutions of hyperbolic black holes with scalar hair in anti-de Sitter (AdS) space, and they do not have spherical or planar counterparts. The system is obtained by taking a neutral limit of an Einstein-Maxwell-dilaton…
A four-dimensional static black hole solution of Einstein equation conformally coupled to a massive and self interacting scalar field is obtained. A nontrivial scalar solution proposes a weak scalar hair. A dressed black hole shows a trace…
In this paper we, first, present a class of charged rotating solutions in four-dimensional Einstein-Maxwell-dilaton gravity with zero and Liouville-type potentials. We find that these solutions can present a black hole/string with two…
It is argued that an electronically charged dilaton black hole can support a long range field of a Nielsen-Olesen string. Combining both numerical and perturbative techniques we examine the properties of an Abelian-Higgs vortex in the…
Black holes offer a unique laboratory for fundamental physics and are crucial for probing theories beyond Einstein's theory of General Relativity. In this paper, we consider 4D effective field theories with scalar fields. We focus on…
In supersymmetric theories the mass of any state is bounded below by the values of some of its charges. The corresponding bounds in case of Schwarzschild and Reissner-Nordstr\"om black holes are known to coincide with the requirement that…
We consider N=2 supergravity in four dimensions with small R^2 curvature corrections. We construct large charge extremal supersymmetric and non-supersymmetric black hole solutions in all space, and analyze their thermodynamic properties.