Spherical Lumps in the Cosmic Custard

Abstract

Because Large Scale Structures (LSS) are homogeneous up to a very high degree, Standard Perturbation Theory is a common tool to describe the dynamics. Effective Field Theory (EFT) gives an even better description because it takes short-scale nonlinear inhomogeneities into account. The parameters of this EFT of LSS can be found using observations or N-body simulations. In this thesis it is tried to find the parameters analytically in a very specific case, viz. Spherical Collapse. Unfortunately there was too little time to compute these parameters, but there are some useful results which could lead to the solution and give a better understanding of the parameters for the cosmic web in the real (not spherically symmetric) Universe. Also, there are some corrections to earlier calculations of the EFT parameters in SPT published by D. Baumann et al. (http://arxiv.org/abs/1004.2488).