Related papers: Brane induced gravity: Ghosts and naturalness
All the models of elementary particles and their interactions derived from String Theory involve a compact six-dimensional internal space. Its volume and shape should be fixed or stabilized, since otherwise massless scalar fields (moduli)…
Completely regular tensionful codimension-n brane world solutions are discussed, where the core of the brane is chosen to be a thin codimension-(n-1) shell in an infinite volume flat bulk, and an Einstein-Hilbert term localized on the brane…
Generically, non-linear bimetric theories of gravity suffer from the same Boulware-Deser ghost instability as non-linear theories of massive gravity. However, recently proposed theories of massive gravity have been shown to be ghost-free.…
Inspired by the work [Eur. Phys. J. C 78 (2018) 45], we study the linear tensor perturbation of both the flat and bent thick branes with inner structure in two-field mimetic gravity. The master equations for the linear tensor perturbations…
We study the stabilization of one spatial dimension in (p+1+1)-dimensional spacetime in the presence of $p$-dimensional brane(s), a bulk cosmological constant and the Casimir force generated by a conformally coupled scalar field. We find…
We analyze a class of 5D models where a 3 brane is generated by a bulk scalar field non minimally coupled to gravity. We show that perturbative stability of such branes is normally guaranteed although non minimal couplings are not innocuous…
We discuss the weak gravitational field created by isolated matter sources in the Randall-Sundrum brane-world. In the case of two branes of opposite tension, linearized Brans-Dicke (BD) gravity is recovered on either wall, with different BD…
Weak gravity in the brane world scenario with a scalar field in the bulk between two end-of-the-world branes is investigated by using the doubly gauge invariant formalism. We review the result that Einstein gravity is restored in the low…
A mechanism for localization of quantum fields on a $s$-brane, representing the boundary of a s+2 dimensional bulk space, is investigated. Minkowski and AdS bulk spaces are analyzed. Besides the background geometry, the relevant parameters…
Stability and localization of the gravitational perturbations for a special brane system in Eddington-inspired Born-Infeld (EiBI) gravity were studied in [Phys. Rev. D 85, 124053 (2012)]. In this paper, we show that the gravitational…
We show that, under general assumptions, in six-dimensional brane-world models with compactified large extra dimensions, the energy density of brane oscillations scales as that of cold dark matter and its present value is compatible with…
It has been proposed that the geometry of an extra dimension could automatically adjust itself to compensate for an arbitrary energy density on the 3-D brane which we are presumed to inhabit, such that a static solution to Einstein's…
Recently, inspired by Eddington's theory, an alternative gravity called Eddington-inspired Born-Infeld gravity was proposed by Ba$\tilde{\text{n}}$ados and Ferreira. It is equivalent to Einstein's general relativity in vacuum, but deviates…
We analyze, within the framework of unified brane gravity, the weak-field perturbations caused by the presence of matter on a 3-brane. Although deviating from the Randall-Sundrum approach, the masslessness of the graviton is still…
Five-dimensional cosmological models with two 3-branes and with a buck cosmological constant are studied. It is found that for all the three cases ($\Lambda =0$, $\Lambda >0$, and $\Lambda <0$), the conventional space-time singularity ``big…
We consider compactifications of six dimensional gravity in four dimensional Minkowski or de Sitter space times a two dimensional sphere, S^2. As has been recently pointed out, it is possible to introduce 3-branes in these backgrounds with…
The quantum theory of a free particle on a portion of two-dimensional Euclidean space bounded by a circle and subject to non-local boundary conditions gives rise to bulk and surface states. Starting from this well known property, a…
The non-linear behaviour of Randall-Sundrum gravity with one brane is examined. Due to the non-compact extra dimension, the perturbation spectrum has no mass gap, and the long wavelength effective theory is only understood perturbatively.…
Gravity in five-dimensional braneworld backgrounds often exhibits problematic features, including kinetic ghosts, strong coupling, and the vDVZ discontinuity. These problems are an obstacle to producing and analyzing braneworld models with…
We study cosmological perturbations for a ghost free massive gravity theory formulated with a dynamical extra metric that is needed to massive deform GR. In this formulation FRW background solutions fall in two branches. In the dynamics of…