Shell-crossing in a ΛCDM Universe

Author(s)
Cornelius Rampf, Oliver Hahn
Abstract

Perturbation theory is an indispensable tool for studying the cosmic large-scale structure, and establishing its limits is therefore of utmost importance. One crucial limitation of perturbation theory is shell-crossing, which is the instance when cold-dark-matter trajectories intersect for the first time. We investigate Lagrangian perturbation theory (LPT) at very high orders in the vicinity of the first shell-crossing for random initial data in a realistic three-dimensional Universe. For this, we have numerically implemented the all-order recursion relations for the matter trajectories, from which the convergence of the LPT series at shell-crossing is established. Convergence studies performed at large orders reveal the nature of the convergence-limiting singularities. These singularities are not the well-known density singularities at shell-crossing but occur at later times when LPT already ceased to provide physically meaningful results.

Organisation(s)
Department of Mathematics, Department of Astrophysics
External organisation(s)
Université Côte d'Azur
Journal
Monthly Notices of the Royal Astronomical Society: Letters
Volume
501
Pages
L71-L75
No. of pages
5
ISSN
1745-3925
Publication date
02-2021
Peer reviewed
Yes
Austrian Fields of Science 2012
103004 Astrophysics, 103044 Cosmology, 101028 Mathematical modelling
Keywords
ASJC Scopus subject areas
Astronomy and Astrophysics, Space and Planetary Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/aae27650-af49-45b3-8073-4525748f4ce6