A first comparison of Kinetic Field Theory with Eulerian Standard Perturbation Theory
Abstract
We present a detailed comparison of the newly developed particle-based Kinetic Field Theory framework for cosmic large-scale structure formation with the established formalism of Eulerian Standard Perturbation Theory. We highlight the qualitative differences of both approaches by a comparative analysis of the respective equations of motion and implementation of initial conditions. A natural starting point for a first quantitative comparison is given by the non-interacting regime of free-streaming kinematics. Our results suggest that Kinetic Field Theory contains a complete resummation of Standard Perturbation Theory in this regime. We further show that the exact free-streaming solution of Kinetic Field Theory can not be recovered in any finite order of Standard Perturbation Theory. Kinetic Field Theory should therefore provide a better starting point for perturbative treatments of non-linear structure formation.
Keywords
Cite
@article{arxiv.2012.05812,
title = {A first comparison of Kinetic Field Theory with Eulerian Standard Perturbation Theory},
author = {Elena Kozlikin and Robert Lilow and Felix Fabis and Matthias Bartelmann},
journal= {arXiv preprint arXiv:2012.05812},
year = {2021}
}