Related papers: Tachyons in a slice of AdS
We study linear and nonlinear stability of asymptotically AdS$_4$ solutions in Einstein-Maxwell-scalar theory. After summarizing the set of static solutions we first examine thermodynamical stability in the grand canonical ensemble and the…
We consider the quantisation of scalar fields on a Lifshitz background, exploring the possibility of alternative boundary conditions, allowing the slow falloff mode to fluctuate. We show that the scalar field with alternative boundary…
This paper considers the spacetimes describing pp-waves propagating on extremal non-dilatonic branes. It is shown that an observer moving along a geodesic will experience infinite curvature at the horizon of the brane, which should…
In this work, we review and extend the so-called consistency conditions for the existence of a braneworld scenario in arbitrary dimensions in the Brans-Dicke (BD) gravitational theory. After that, we consider the particular case of a…
Compactified AdS space can not be mapped into just one Poincare coordinate chart. This implies that the bulk field spectrum is discrete despite the infinite range of the coordinates. We discuss here why this discretization of the field…
We investigate the stability of asymptotically anti-de Sitter gravity coupled to tachyonic scalar fields with mass at or slightly above the Breitenlohner-Freedman bound. The boundary conditions in these ``designer gravity'' theories are…
The phenomenon of superradiance in the context of asymptotically global AdS spacetimes is investigated with particular accent on its effect on the stability of the systems under consideration. To this end, the concept of an asymptotically…
The AdS/CFT correspondence is applied to a close analogue of the little hierarchy problem in $AdS_{d+1}$, $d \geq 3$. The new mechanism requires a Maxwell field that gauges a $U(1)_R$ symmetry in a bulk supergravity theory with a negative…
We discuss brane world sum rules for compactifications involving an arbitrary number of spacetime dimensions. One of the most striking results derived from such consistency conditions is the necessity for negative tension branes to appear…
By carefully analyzing the radial part of the wave-equation for a scalar field in AdS, we show that for a particular range of boundary conditions on the scalar field, the radial spectrum contains a bound state. Using the AdS/CFT…
We consider a model of brane world gravity in the context of non-conformal non-SUSY matter. In particular we modify the earlier strong coupling solution to the glueball spectrum in an $AdS^7$ Black Hole by introducing a Randall-Sundrum…
Stability of massive antisymmetric tensor fields with the Chern-Simons type action in anti de Sitter spacetime is studied. It is found that there exists a complete set of solutions whose energy is conserved and positive definite if the mass…
We study the stability of the RS brane embedded in the AdS$_5$ vacuum of 5d gauged supergravity, where many tachyonic scalars exist. We consider a model in which these scalars couple to the brane such that the BPS conditions are satisfied…
We propose a field theory for describing the tachyon on a brane-antibrane system near the minimum of the potential. This field theory realizes two known properties of the tachyon effective action: 1) absence of plane-wave solutions around…
Boundary conditions for massive fermions are investigated in AdS_d for $d \ge 2$. For fermion masses in the range $0 \le |m| < 1/2\ell$ with $\ell$ the AdS length, the standard notion of normalizeability allows a choice of boundary…
The geometry of spinning codimension-two branes in AdS spacetime is analyzed in three and higher dimensions. The construction of non-extremal solutions is based on identifications in the covering of AdS space by isometries that have fixed…
We study the stability of f(R)-AdS (Schwarzschild-AdS) black hole obtained from f(R) gravity. In order to resolve the difficulty of solving fourth order linearized equations, we transform f(R) gravity into the scalar-tensor theory by…
It is well-known that a hypothetical particle which moves faster than the light, a \emph{tachyon}, is unstable in the Minkowski space-time. Here we shall show that, contrary to the Minkowski case, the tachyon is stable in the rotating…
We study the semi-classical dynamics of a scalar field in the background of a black hole in an asymptotically AdS (AAdS) spacetime, in the framework of the Hamiltonian formulation of General Relativity. The small diffeomorphism (gauge)…
We explore various facets of the cosmology of the Randall-Sundrum scenario with two branes by considering the dynamics of the branes moving in a bulk AdS/Schwarzschild geometry. This approach allows us both to understand in more detail and…