We investigate how various inflationary and bouncing cosmologies can berealized by imperfect fluids with a generalized equation of state, in thecontext of both classical and loop quantum cosmology. With regards to theinflationary cosmologies, we study the intermediate inflation scenario, the$R^2$ inflation scenario and two constant-roll inflation scenarios and withregards to the bouncing cosmologies we study the matter bounce scenario, thesingular bounce and the super bounce scenario. Within the context of theclassical cosmology, we calculate the spectral index of the power spectrum ofprimordial curvature perturbations, the scalar-to-tensor ratio and the runningof the spectral index and we compare the resulting picture with the Planckdata. As we demonstrate, partial compatibility with the observational data isachieved in the imperfect fluid description, however none of the abovescenarios is in full agreement with data. This result shows that although it ispossible to realize various cosmological scenarios using different theoreticalframeworks, it is not guaranteed that all the theoretical descriptions areviable.
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