Spectral indices in Eddington-inspired Born-Infeld inflation
  We investigate the scalar and tensor spectral indices of the quadratic
inflation model in Eddington-inspired Born-Infeld (EiBI) gravity. We find that
the EiBI corrections to the spectral indices are of second and first order in
the slow-roll approximation for the scalar and tensor perturbations
respectively. This is very promising since the quadratic inflation model in
general relativity provides a very nice fit for the spectral indices. Together
with the suppression of the tensor-to-scalar ratio EiBI inflation agrees well
with the observational data.
