Related papers: Flux Compactifications: Stability and Implications…
Extra-dimensional scenarios have become widespread among particle and gravitational theories of physics to address several outstanding problems, including cosmic acceleration, the weak hierarchy problem, and the quantization of gravity. In…
We analyse the cosmological implications of brane-antibrane systems in string-theoretic orbifold and orientifold models. In a class of realistic models, consistency conditions require branes and antibranes to be stuck at different fixed…
We investigate cosmological solutions of eleven dimensional supergravity compactified on a squashed seven manifold. The effective action for the four dimensional theory contains scalar fields describing the size and squashing of the…
We investigate cosmologies with homogeneous extra dimensions that can be described by generalised Friedmann-Robertson-Walker metrics and give a brief review on a general setup to describe a broad range of standard stabilization and…
We consider a toy cosmological model with a gas of wrapped Dp-branes in 10-dimensional dilaton gravity compactified on a p-dimensional Ricci flat internal manifold. A consistent generalization of the low energy effective field equations in…
In a cosmological context, the Einstein-Gauss-Bonnet theory contains, in $d+4$ dimensions, a dynamical compactification scenario in which the additional dimensions settle down to a configuration with a constant radion/scale factor. Sadly…
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)…
We consider the conundrum of generating de Sitter space from higher-dimensional geometry, with particular attention to KKLT-type constructions arXiv:hep-th/0301240 and their 5d implications. We show that even in the probe approximation with…
We analyze various phases of inflation based on the anomaly-induced effective action of gravity (modified Starobinsky model), taking the cosmological constant Lambda and k=0, +/- 1 topologies into account. The total number of the…
We illustrate a framework for constructing models of chaotic inflation where the inflaton is the position of a D3 brane along the universal cover of a string compactification. In our scenario, a brane rolls many times around a non-trivial…
In gravitational theories with extra dimensions, it is argued that the existence of a positive vacuum energy generically implies catastrophic instability of our four-dimensional world. The most generic instability is a decompactification…
We examine the cosmology of the Randall-Sundrum model in a dynamic setting where scalar fields are present in the bulk as well as the branes. This generates a mechanism similar to that of Goldberger-Wise for radion stabilization and the…
In Schroedinger picture we study the possible effects of trans-Planckian physics on the quantum evolution of massive non-minimally coupled scalar field in de Sitter space. For the nonlinear Corley-Jacobson type dispersion relations with…
In low scale quantum gravity scenarios the fundamental scale of nature can be as low as TeV, in order to address the naturalness of the electroweak scale. A number of difficulties arise in constructing specific models; stabilisation of the…
We present an exact solution for a factorizable brane-world spacetime with two extra dimensions and explicit brane sources. The compactification manifold has the topology of a two-sphere, and is stabilized by a bulk cosmological constant…
We study the Randall-Sundrum model with a small 4D effective cosmological constant on the brane, and drive a corrected radion potential following the Goldberger-Wise mechanism. We then discuss the effect of the 4D effective cosmological…
We solve the Einstein's equation in five-dimensional spacetime for Randall Sundrum Brane world model with time dependent radion field to study variation of brane scale factor with time. We have shown that as radion field decreases with time…
The dynamics of a stabilized radion in the Randall-Sundrum model (RS) with two branes is investigated, and the effects of the radion on electroweak precision observables are evaluated. The radius is assumed to be stabilized using a bulk…
We consider the possibility that higher-curvature corrections could drive inflation after the compactification to four dimensions. Assuming that the low-energy limit of the fundamental theory is eleven-dimensional supergravity to the lowest…
We propose a new radion stabilization mechanism in the Randall-Sundrum spacetime, introducing a bulk ${SU(N_H)}$ gauge field which confines at a TeV scale. It turns out that the radion is stabilized by the balance between a brane tension…