Heierarchical Structure Formation

the cosmological distance ladder is quite fascinating Terry Tao himself: https://www.youtube.com/watch?v=hFMaT9oRbs4

galaxies seem to be distributed as strands, of clusters and superclusters, forming the cosmic web

but that means projected structure formation would be helpful as an effective theory? diffuse -> sheets -> filaments -> knots

it’s a reduction in the codimension of the surviving large-scale structure -chatgpt

the main equations of motion are: 1. poisson equation 2. boltzmann equation

the main observables are: * power spectrum of CMB, galaxies (scalars from scalars) * lensing of CMB, galaxy shapes (vectors from scalars) * kSZ, RSD, pecular velocities (scalars from vectors) * cross-correlations (vectors from vectors)

these seem to be consequences either from where the density is, or, from how the density is moving some are sensitive to time-evolution, some integrate over all history