Related papers: Inflation versus collapse in brane matter
Brane world gravity looks different for observers on positive and negative tension branes. First we consider the well-known RS1 model with two branes embedded into the AdS_5 space-time and recall the results on the relations between the…
In brane world scenarios with a bulk scalar field between two branes it is known that 4-dimensional Einstein gravity is restored at low energies on either brane. By using a gauge-invariant gravitational and scalar perturbation formalism we…
We consider real and complex scalar fields non-minimally coupled to gravity in the bulk spacetime and study their impact on the brane upon acquiring a non-vanishing vacuum expectation value. When examining the case of the complex scalar…
The action for a non-BPS p=2 brane embedded in a flat N=1, D=4 target superspace is obtained through the method of nonlinear realizations of the associated super-Poincare symmetries. The brane excitation modes correspond to the…
Extra-dimensional models can involve bulk pseudo-Goldstone bosons (pGBs) whose shift symmetry is explicitly broken only by physics localized on branes. Reliable calculation of their low-energy potential is often difficult because it…
We investigate the generation of primordial gravitational waves from inflation in braneworld cosmologies with extra dimensions. Advantage of using primordial gravitational waves to probe extra dimensions is that their theory depends only on…
We consider black $p$-brane solutions of the low energy string action, computing scalar perturbations. Using standard methods, we derive the wave equations obeyed by the perturbations and treat them analytically and numerically. We have…
We discuss the dynamics of intersecting $p$-branes with cosmological constants in the higher-dimensional gravity theories. For the delocalized brane case, these solutions describe an asymptotically de Sitter or power-law expanding universe,…
We demonstrate that there exists an inflationary solution on the positive tension brane in the Randall-Sundrum scenario. Inflation is driven by a slow-rolling scalar field on the brane and is achieved within the perturbative limit of the…
Theories with elementary scalar degrees of freedom seem nowadays required for simple descriptions of the Standard Model and of the Early Universe. It is then natural to embed theories of inflation in supergravity, also in view of their…
We compute the quantum fluctuations of a 3-brane with tension, energy density and stiffness. As a result of the fluctuations there are induced forces between massive objects living on the brane. We study various limiting cases of the…
For relativistic quantum field theories, we consider Lorentz breaking, spatially homogeneous field configurations or states that evolve in time along a symmetry direction. We dub this situation "spontaneous symmetry probing" (SSP). We…
We discuss inflationary cosmology in a five dimensional SO(10) model compactified on $S^1/(Z_2\times Z_2')$, which yields $SU(3)_c\times SU(2)_L\times U(1)_Y\times U(1)_X$ below the compactification scale. The gauge symmetry $SU(5)\times…
We describe a simple mechanism that can lead to inflation within string-based brane-world scenarios. The idea is to start from a supersymmetric configuration with two parallel static Dp-branes, and slightly break the supersymmetry…
We derive the gauge invariant perturbation equations for a 5-dimensional bulk spacetime in the presence of a brane. The equations are derived in full generality, without specifying a particular energy content of the bulk or the brane. We do…
We consider a quantization of scalar perturbations about a de Sitter brane in a 5-dimensional anti-de Sitter (AdS) bulk spacetime. We first derive the second order action for a master variable $\Omega$ for 5-dimensional gravitational…
This paper is dedicated to revisit the modifications caused by branes in the collapse of a stellar structure under the Snyder-Oppenheimer scheme. Due to the homogeneity and isotropy of the model, we choose study the case of a closed…
In higher dimensional models where the gauge and gravity fields live in the bulk and the matter fields only in a brane, we point out the importance of the brane (transverse) coordinate modes, which are the Nambu-Goldstone bosons appearing…
We consider gravitationally induced perturbations of relativistic Dirac--Goto--Nambu membranes and strings (or {\it p}-branes). The dynamics are described by the first and second fundamental tensors, and related curvature tensors in an {\it…
We consider a warped brane world scenario with two branes, Gauss-Bonnet gravity in the bulk, and brane localised curvature terms. When matter is present on both branes, we investigate the linear equations of motion and distinguish three…