Trapped Inflation
  We analyze a distinctive mechanism for inflation in which particle production
slows down a scalar field on a steep potential, and show how it descends from
angular moduli in string compactifications. The analysis of density
perturbations -- taking into account the integrated effect of the produced
particles and their quantum fluctuations -- requires somewhat new techniques
that we develop. We then determine the conditions for this effect to produce
sixty e-foldings of inflation with the correct amplitude of density
perturbations at the Gaussian level, and show that these requirements can be
straightforwardly satisfied. Finally, we estimate the amplitude of the
non-Gaussianity in the power spectrum and find a significant equilateral
contribution.
