Thick Domain Walls Intersecting a Black Hole

Classical scalar fields have been proposed as possible candidates for the dark matter component of the universe. Given the fact that super-massive black holes seem to exist at the center of most galaxies, in order to be a viable candidate for the dark matter halo a scalar field configuration should be stable in the presence of a central black hole, or at least be able to survive for cosmological time-scales. In the present work we consider a scalar field as a test field on a ...

It is well known that global topological defects induce a repulsive gravitational potential for test particles. 'What is the gravitational potential induced by black holes with a cosmological constant (Schwarzschild-de Sitter (S-dS) metric) on finite thickness global topological defects?'. This is the main question addressed in the present analysis. We also discuss the validity of Derrick's theorem when scalar fields are embedded in non-trivial gravitational backgrounds. In t...

Recently, static and spherically symmetric configurations of globally regular self-gravitating scalar solitons were found. These configurations are unstable with respect to radial linear perturbations. In this paper we study the dynamical evolution of such configurations and show that, depending on the sign of the initial perturbation, the solitons either collapse to a Schwarzschild black hole or else ``explode'' into an outward moving domain wall.

We study a simple system that comprises all main features of critical gravitational collapse, originally discovered by Choptuik and discussed in many subsequent publications. These features include universality of phenomena, mass-scaling relations, self-similarity, symmetry between super-critical and sub-critical solutions, etc. The system we consider is a stationary membrane (representing a domain wall) in a static gravitational field of a black hole. For a membrane that s...

The interplay between topological defects (branes) and black holes has been a subject of recent study, motivated in part by interest in brane-world scenarios. In this paper we analyze in detail the description of a black hole bound to a domain wall (a two-brane in four dimensions), for which an exact description in the limit of zero wall thickness has been given recently. We show how to smooth this singular solution with a thick domain wall. We also show that charged extremal...

The collapse of sufficiently large closed domain wall produced during second order phase transition in the vacuum state of a scalar field can lead to the formation of black hole. The origin of domain walls with appropriate size and energy density could be a result of evolution of an effectively massless scalar field at the inflational epoch. We demonstrate that in this case the situation is valued when there are compact domains of less favorable vacuum surrounded by a sea of ...

We find Einstein-Yang-Mills (EYM) black hole solutions endowed with massless scalar hair in the presence of a potential $V\left(\phi \right) $ as function of the scalar field $\phi $. Choosing $V\left(\phi \right) =$constant (or zero) sets the scalar field to vanish leaving us with the EYM black holes. Our class of black hole solutions is new so that they do not asymptote in general to any known limits. Particular case is given, however, which admits an asymptotically anti de...

We investigate a self-gravitating thick domain wall for a $\lambda \Phi^4$ potential. The system of scalar and Einstein equations admits two types of non-trivial solutions: domain wall solutions and false vacuum-de Sitter solutions. The existence and stability of these solutions depends on the strength of the gravitational interaction of the scalar field, which is characterized by the number $\epsilon$. For $\epsilon \ll 1$, we find a domain wall solution by expanding the equ...

The functional Schrodinger equation is used to study the quantum collapse of a gravitating, spherical domain wall and a massless scalar field coupled to the metric. The approach includes backreaction of pre-Hawking radiation on the gravitational collapse. Truncating the degrees of freedom to a minisuperspace leads to an integro-differential Schrodinger equation. We define a "black hole" operator and find its eigenstates. The black hole operator does not commute with the Hamil...

The local and global properties of the Goetz thick plane domain wall space-time are studied. It is found that when the surface energy of the wall is greater than a critical value $\sigma_{c}$, the space-time will be closed by intermediate singularities at a finite proper distance. A model is presented in which these singularities will give rise to scalar ones when interacting with null fluids. The maximum extension of the space-time of the wall whose surface energy is less th...