UTAPwiki/セミナー/初期宇宙・相対論速報
Naoya Kobayashi (CITA, U. Toronto)
Title: "Rolling in the Modulated Reheating Scenario"
Abstract: In the modulated reheated scenario, the field that drives inflation has
a spatially-varying decay rate, and the resulting inhomogeneous
reheating process generates adiabatic perturbations. In this talk, I
describe the power spectrum and the bispectrum of the density
perturbations generated in this scenario. Our derivation carefully
follows the dynamics of the field that perturbs the inflaton decay rate.
I will show that the statistics of the perturbations can be greatly
modified by the dynamics of this modulus field, even if the field has a
simple potential and a small effective mass compared to the Hubble
scale. I will present examples in which non-Gaussianity is amplified by
the modulus dynamics to values that are forbidden by Planck. Therefore,
a proper treatment of the modulus dynamics is important in order to
accurately calculate the resulting perturbations from modulated reheating.