Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2011-11-18
Physics
High Energy Physics
High Energy Physics - Theory
32 pages, 15 figures
Scientific paper
We show that the radion in a warped geometry bounded by two branes can have a potential suitable for inflation. Our construction is based upon a solution known in string theory as the linear dilaton, in which the back-reaction from a bulk scalar \Phi is exactly accounted for. The radion, stabilized by \Phi, is much heavier than the TeV scale and its couplings to the standard model are much more suppressed than in the usual Randall-Sundrum solution. We present a new formalism for obtaining approximate time-dependent solutions, based on perturbing the exact solution to the coupled Einstein and scalar field equations in the bulk. It allows the radion potential to be computed directly in terms of the brane potentials for \Phi. We show that simple exponential potentials on the branes can lead to a 4D radion potential with a flattened hilltop form, yielding inflation with a spectral index of typically n_s=0.96 and no higher than 0.99. With more complicated brane potentials, the descent from the hilltop can be a linear potential, giving a tensor-to-scalar ratio as large as r=0.07 with n_s=0.974. The couplings of the radion to the standard model particles are dictated by general covariance, so the details of reheating are explicitly calculable, leading to a reheat temperature of at least 10^7 GeV. The quantum corrections to the inflaton potential from its couplings to matter are also calculable and are shown to be small, so that the prediction for the shape of the potential is under theoretical control, even with superPlanckian field excursions.
Cline James M.
Trudeau Joel
No associations
LandOfFree
Warped Radion Inflation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Warped Radion Inflation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Warped Radion Inflation will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-548426