Quantum collapse as source of the seeds of cosmic structure during the
  radiation era
  The emergence of the seeds of cosmic structure, from a perfect isotropic and
homogeneous Universe, has not been clearly explained by the standard version of
inflationary models as the dynamics involved preserve the homogeneity and
isotropy at all times. A proposal that attempts to deal with this problem, by
introducing "the self-induced collapse hypothesis," has been introduced by D.
Sudarsky and collaborators in previous papers. In all these works, the collapse
of the wave function of the inflaton mode is restricted to occur during the
inflationary period. In this paper, we analyse the possibility that the
collapse happens during the radiation era. A viable model can be constructed
under the condition that the inflaton field variable must be affected by the
collapse while the momentum variable can or cannot be affected. Another
condition to be fulfilled is that the time of collapse must be independent of
$k$. However, when comparing with recent observational data, the predictions of
the model cannot be distinguished from the ones provided by the standard
inflationary scenario. The main reason for this arises from the requirement
that primordial power spectrum obtained for the radiation era matches the
amplitude of scalar fluctuations consistent with the latest CMB observations.
This latter constraint results in a limit on the possible times of collapse and
ensures that the contribution of the inflaton field to the energy-momentum
tensor is negligible compared to the contribution of the radiation fields.
