A principal component approach to structure formation with massive neutrinos

It will soon become possible to study the evolution of large scale structures with tomographic weak lensing surveys, such as DES and LSST. This will provide a powerful way of constraining the current cosmological model, LCDM, which assumes that neutrinos have zero mass. On linear scales, any small departure of the growth dynamics from the LCDM prediction can be described in terms of two functions of time and scale. Zhao et al derived the principal components of these two functions that will be best constrained by DES and LSST. This thesis demonstrates the possibility of using these principal components to derive the expected constraints on the neutrino mass. It also discusses the effects of neutrino mass on the evolution of cosmological perturbations, and their effect on observables, such as the matter density contrast and the CMB spectrum.