Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2007-10-14
Phys.Rev.D77:063503,2008
Physics
High Energy Physics
High Energy Physics - Theory
21 pages; v2 references added, minor clarifications
Scientific paper
10.1103/PhysRevD.77.063503
We present a mechanism to transfer the spectrum of perturbations in a scalar isocurvature field $\xi$ onto the matter content in the radiation era via modulated, instant preheating after ekpyrosis. In this setup, $\xi$ determines the coupling constant relevant for the decay of a preheat matter field into Fermions. The resulting power spectrum is scale invariant if $\xi$ remains close to a scaling solution in new ekpyrotic models of the universe; by construction the spectrum is independent of the detailed physics near the bounce. The process differs from the curvaton mechanism, which has been used recently to revive the ekpyrotic scenario, in that no peculiar behavior of $\xi$ shortly before or during the bounce is needed. In addition, a concrete and efficient realization of reheating after ekpyrosis is provided; this mechanism is not tied to ekpyrotic models, but could equally well be used in other setups, for instance inflationary ones. We estimate non-Gaussianities and find no additional contributions in the most simple realizations, in contrast to models using the curvaton mechanism.
No associations
LandOfFree
Modulated Perturbations from Instant Preheating after new Ekpyrosis 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 Modulated Perturbations from Instant Preheating after new Ekpyrosis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Modulated Perturbations from Instant Preheating after new Ekpyrosis will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-383801