MG12 - Talk detail
 

Back to previous page

 Participant 

Institution

Session

Talk

Abstract

Primordial Power Spectrum from a Contracting Pre-Bounce Phase

In this work we study the metric perturbations generated in a contracting universe. This study is important in many non-singular models since the power spectrum of such perturbations will provide the starting point for the standard hot expanding universe. In a hydrodynamical model with a single dust like fluid, it was shown that spectral index is almost scale invariant, i.e., $n_s \gtrsim 1$. We present a two fluid model, dust and radiation, which we evolve numerically the perturbations from an initial adiabatic vacuum placed at the infinity past. We obtain that even though the perturbation freeze-out long before the radiation era, it changes the spectrum to a non-constant $n_s$ varying from a slight greater then one to slight lesser the one, i.e., $n_s \lesssim 1$.

Back to previous page