Primordial power spectrum constraints from astrophysical observations

This thesis will investigate constraints on the primordial power spectrum coming from a variety of current and future astrophysical experiments. In particular, we will focus on the limits that can be obtained on the running parameters of the primordial power spectrum from 21 cm Intensity Mapping experiments targeted towards the Dark Ages. We will also investigate the possibility of Primordial Black Holes formation from curvature perturbations in the early Universe and determine whether Intensity Mapping experiments will be able to detect the departure from scale invariance that lead to their formation.