Dirac-field model of inflation in Einstein-Cartan theory
  We present a cosmological model in which a single Dirac field with a flat
potential can give rise to inflation within the framework of the
Einstein-Cartan theory. It is shown that our Dirac-field model leads to a
nearly scale-invariant spectrum of density fluctuations owing to the
spin-interaction which naturally arises from the field equations of the
Einstein-Cartan theory.
