Resurrecting power law inflation in the light of Planck results
  It is well known that a canonical scalar field with an exponential potential
can drive power law inflation (PLI). However, the tensor-to-scalar ratio in
such models turns out to be larger than the stringent limit set by recent
Planck results. We propose a new model of power law inflation for which the
scalar spectra index, the tensor-to-scalar ratio and the non-gaussianity
parameter $f_{_{\mathbf{NL}}}^{\mathrm{equil}}$ are in excellent agreement with
Planck results. Inflation, in this model, is driven by a non-canonical scalar
field with an inverse power law potential. The Lagrangian for our model is
structurally similar to that of a canonical scalar field and has a power law
form for the kinetic term. A simple extension of our model resolves the
graceful exit problem which usually afflicts models of power law inflation.
