9 research outputs found
A relativistic calculation of super-Hubble suppression of inflation with thermal dissipation
We investigated the evolution of the primordial density perturbations
produced by inflation with thermal dissipation. A full relativistic analysis on
the evolution of initial perturbations from the warm inflation era to a
radiation-dominated universe has been developed. The emphasis is on tracking
the ratio between the adiabatic and the isocurvature mode of the initial
perturbations. This result is employed to calculate a testable factor: the
super-Hubble suppression of the power spectrum of the primordial perturbations.
We show that based on the warm inflation scenario, the super-Hubble suppression
factor, , for an inflation with thermal dissipation is at least 0.5. This
prediction does not depend on the details of the model parameters. If is
larger than 0.5, it implies that the friction parameter is larger than
the Hubble expansion parameter during the inflation era.Comment: 22 pages, 3 figures, use RevTex, accepted by Class. Quant. Gra
Mass Density Perturbations from Inflation with Thermal Dissipation
We study the power spectrum of the mass density perturbations in an inflation
scenario that includes thermal dissipation. We show that the condition on which
the thermal fluctuations dominate the primordial density perturbations can
easily be realized even for weak dissipation, i.e., the rate of dissipation is
less than the Hubble expansion. We find that our spectrum of primordial density
perturbations follows a power law behavior, and exhibits a ``thermodynamical''
feature -- the amplitude and power index of the spectrum depend mainly on the
thermodynamical variable , the inflation energy scale. Comparing this result
with the observed temperature fluctuations of the cosmic microwave background,
we find that both amplitude and index of the power spectrum can be fairly well
fitted if GeV.Comment: 23 pages, 7 figures, REVTex; Phys. Rev. D in pres