  If the large scale anomalies in the temperature power spectrum of the cosmic
microwave background are of primordial origin, they may herald modifications to
the slow roll inflationary paradigm on the largest scales. We study the
possibility that the origin of the large scale power suppression is a
modification of initial conditions during slow roll as a result of a pre-slow
roll phase during which the inflaton evolves rapidly. This stage is manifest in
a potential in the equations for the Gaussian fluctuations during slow roll and
modify the power spectra of scalar perturbations via an initial condition
transfer function $\mathcal{T}(k)$. We provide a general analytical study of
its large and small scale properties and analyze the impact of these initial
conditions on the infrared aspects of typical test scalar fields. The infrared
behavior of massless minimally coupled test scalar field theories leads to the
dynamical generation of mass and anomalous dimensions, both depend
non-analytically on $\mathcal{T}(0)$. During inflation all quanta decay into
many quanta even of the same field because of the lack of kinematic thresholds.
The decay leads to a quantum entangled state of sub and superhorizon quanta
with correlations across the horizon. We find the modifications of the decay
width and the entanglement entropy from the initial conditions. In all cases,
initial conditions from a ``fast-roll'' stage that lead to a suppression in the
scalar power spectrum at large scales also result in a suppression of the
dynamically generated masses, anomalous dimensions and decay widths.
