Perturbations of the FRW Universe and Formation of Large Scale Structures

Abstract

Observations of cosmic microwave background and large scale structures are the main tools of precision cosmology whereby theories of dark matter, inflation, neutrino mass are tested with data from Planck, SDSS and other such experiments. Large scale structures like galaxies and clusters of galaxies are formed when matter perturbations grow as pressure-less cold dark matter falls into the gravitational potential of the primordial perturbations which are believed to arise from a period of inflation. In this chapter we will work out the general relativistic theory of density perturbations which will be used for comparing observations with theories of particle physics and cosmology.