Inflating without a flat potential: Viscous inflation
  Bulk viscosity leads to negative pressure, which is a key ingredient for
successful inflation. We build an inflationary model where the slow-roll of the
inflaton field is driven by a viscous component instead of the flat potential
commonly used. Since viscosity does not contribute to the energy density of the
Universe, the Hubble rate depends only on the kinetic energy of the inflaton.
The power spectrum is almost scale-invariant, with a tilt depending on the
slow-roll parameters defined within the model.
