Related papers: Thick Brane Worlds and Their Stability
We present some exact non-uniform black string solutions of 5-dimensional pure Einstein gravity as well as Einstein-Maxwell-dilaton theory at arbitrary dilaton coupling. The solutions share the common property that their 4-dimensional…
The bigravity models coupled with two scalar fields are constructed. We show that a wide class of the expansion history of the universe, especially corresponding to dark energy and/or inflation, can be described by a solution of the…
We suggest a mechanism which leads to 3+1 space-time dimensions. The Universe assumed to have nine spatial dimensions is regarded as a special nonlinear oscillatory system -- a kind of Einstein solid. There are p-brane solutions which…
This work deals with the presence of defect structures in models described by real scalar field in a diversity of scenarios. The defect structures which we consider are static solutions of the equations of motion which depend on a single…
We derive and solve the full set of scalar perturbation equations for a class of $Z_2$-symmetric five-dimensional geometries generated by a bulk cosmological constant and by a 3-brane non-minimally coupled to a bulk dilaton field. The…
Thickness corrections to static, axisymmetric Dirac-Nambu-Goto branes embedded into spherically symmetric black hole spacetimes with arbitrary number of dimensions are studied. First, by applying a perturbative approximation, it is found…
We study a generalization of the Randall-Sundrum mechanism for generating the weak/Planck hierarchy, which uses two rather than one warped extra dimension, and which requires no negative tension branes. A 4-brane with one exponentially…
The family of brane-world solutions of d+1-dimensional dilatonic gravity is presented. It includes flat brane with small cosmological constant and (anti) de Sitter brane, dilatonic brane-world black holes (Schwarzschild-(anti-) de Sitter,…
Maximally symmetric curved-brane solutions are studied in dilatonic braneworld models which realise the self-tuning of the effective four-dimensional cosmological constant. It is found that no vacua in which the brane has de Sitter or…
We consider linear gravitational perturbations of the Kerr brane, an exact solution of vacuum Einstein's equations in dimensions higher than four and a low-energy solution of string theory. Decomposing the perturbations in tensor harmonics…
Negative mass makes perfect physical sense as long as the dominant energy condition is satisfied by the corresponding energy-momentum tensor. Heretofore, only {\it configurations} of negative mass had been found…
We use nonlinear perturbation theory to obtain new solutions for brane world models that incorporate a massive bulk scalar field. We then consider tensor perturbations and show that Newtonian gravity is recovered on the brane for both a…
We analyse global aspects of 7-brane backgrounds with a non-commuting profile for their worldvolume scalars, also known as T-branes. In particular, we consider configurations with no poles and globally well-defined over a compact K\"ahler…
We consider ``brane universe'' with nonzero tension in the models with large extra dimensions. We find exact solutions of higher-dimensional Einstein equations with single flat Minkowsky brane of arbitrary large tension (or brane…
Braneworld scenarios with compact extra-dimensions need the volume of the extra space to be stabilized. Goldberger and Wise have introduced a simple mechanism, based on the presence of a bulk scalar field, able to stabilize the radius of…
The nature of gravity and its strength compared with other forces are fundamental challenges faced by the actual science. A path to understanding the hierarchy problem of gravity consists in adding an extra dimension to Einstein-Hilbert's…
We present Poincare invariant domain wall (``3-brane'') solutions to some 5-dimensional effective theories which can arise naturally in string theory. In particular, we find theories where Poincare invariant solutions exist for arbitrary…
We review recent works on the possibility for eternal existence of thin-shell wormholes on Einstein and Einstein-Gauss-Bonnet gravity. We introduce thin-shell wormholes that are categorized into a class of traversable wormhole solutions.…
Quadratic scale-invariant gravity non minimally coupled to a scalar field provides a competitive model for inflation, characterized by the transition from an unstable to a stable fixed point, both characterized by constant scalar field…
Some black hole mimickers, as well as black strings and other higher-dimensional spacetimes, exhibit stable light rings-regions where light or high-frequency gravitational waves can be trapped. In these regions, linear perturbations decay…