Inflation Driven by Unification Energy
  We examine the hypothesis that inflation is primarily driven by vacuum energy
at a scale indicated by gauge coupling unification. Concretely, we consider a
class of hybrid inflation models wherein the vacuum energy associated with a
grand unified theory condensate provides the dominant energy during inflation,
while a second "inflaton" scalar slow-rolls. We show that it is possible to
obtain significant tensor-to-scalar ratios while fitting the observed spectral
index.
