Fourth order deformed general relativity
  Whenever the condition of anomaly freedom is imposed within the framework of
effective approaches to loop quantum cosmology, one seems to conclude that a
deformation of general covariance is required. Here, starting from a general
deformation we regain an effective gravitational Lagrangian including terms up
to fourth order in extrinsic curvature. We subsequently constrain the form of
the corrections, and then investigate the conditions for the occurrence of a
big bounce and the realisation of an inflationary era, in the presence of a
perfect fluid or scalar field.
