  We investigate how various inflationary and bouncing cosmologies can be
realized by imperfect fluids with a generalized equation of state, in the
context of both classical and loop quantum cosmology. With regards to the
inflationary cosmologies, we study the intermediate inflation scenario, the
$R^2$ inflation scenario and two constant-roll inflation scenarios and with
regards to the bouncing cosmologies we study the matter bounce scenario, the
singular bounce and the super bounce scenario. Within the context of the
classical cosmology, we calculate the spectral index of the power spectrum of
primordial curvature perturbations, the scalar-to-tensor ratio and the running
of the spectral index and we compare the resulting picture with the Planck
data. As we demonstrate, partial compatibility with the observational data is
achieved in the imperfect fluid description, however none of the above
scenarios is in full agreement with data. This result shows that although it is
possible to realize various cosmological scenarios using different theoretical
frameworks, it is not guaranteed that all the theoretical descriptions are
viable.

General Relativity and Quantum Cosmology