Building Models of Inflation in No-Scale Supergravity
  After reviewing the motivations for cosmological inflation formulated in the
formalism of supersymmetry, we argue that the appropriate framework is that of
no-scale supergravity. We then show how to construct within this framework
inflationary models whose predictions for the tilt in the spectrum of scalar
perturbations, $n_s$, and the ratio, $r$, of tensor and scalar perturbations
coincide with those of the $R + R^2$ model of inflation proposed by
Starobinsky. A more detailed study of no-scale supergravity reveals a structure
that is closely related to that of $R^2$ modifications of the minimal
Einstein-Hilbert action for general relativity, opening avenues for
constructing no-scale de Sitter and anti-de Sitter models by combining pairs of
Minkowski models, as well as generalizations of the original no-scale
Starobinsky models of inflation. We then discuss the phenomenology of no-scale
models of inflation, including inflaton decay and reheating, and then the
construction of explicit scenarios based on SU(5), SO(10) and string-motivated
flipped SU(5)$\times$U(1) GUT models. The latter provides a possible model of
almost everything below the Planck scale, including neutrino masses and
oscillations, the cosmological baryon asymmetry and cold dark matter, as well
as $n_s$ and $r$.
