Recent times: neutrinos and structure formation
There are several ways to observe the large-scale structure of our universe on different scales and redshifts. This structure is even more sensitive to the neutrino abundance, mass spectrum and properties than CMB anisotropies, and offers several opportunities to measure neutrino parameters. If the universe can be described by general relativity and does not feature significant dark energy perturbations, all observables related to large-scale structure can be inferred from the matter power spectrum P(η, k) defined through
Here δM is the relative density perturbation of nonrelativistic ...