Cosmological parameter estimation and the inflationary cosmology

Leach SM, Liddle AR, Martin J, Schwarz D. Cosmological parameter estimation and the inflationary cosmology. PHYSICAL REVIEW D. 2002;66(2): 023515.We consider approaches to cosmological parameter estimation in the inflationary cosmology, focusing on the required accuracy of the initial power spectra. Parametrizing the spectra, for example by power laws, is well suited to testing the inflationary paradigm but will only correctly estimate cosmological parameters if the parametrization is sufficiently accurate, and we investigate conditions under which this is achieved both for present data and for upcoming satellite data. If inflation is favored, reliable estimation of its physical parameters requires an alternative approach adopting its detailed predictions. For slow-roll inflation, we investigate the accuracy of the predicted spectra at first and second order in the slow-roll expansion (presenting the complete second-order corrections for the tensors for the first time). We find that, within the presently allowed parameter space, there are regions where it will be necessary to include second-order corrections to reach the accuracy requirements of MAP and Planck satellite data. We end by proposing a data analysis pipeline appropriate for testing inflation and for a cosmological parameter estimation from high-precision data