Non-linear dark matter collapse under diffusion

TL;DR

This paper investigates the non-linear collapse of dark matter with diffusion into dark energy, providing constraints on diffusion magnitude and reinforcing linear theory results.

Contribution

It introduces a non-linear spherical collapse model with velocity diffusion into dark energy, extending previous linear perturbation analyses.

Findings

Constraints on maximum dark matter diffusion magnitude

Reinforcement of linear perturbation theory results

Insights into dark matter-dark energy interactions

Abstract

Diffusion is one of the physical processes allowed for describing the large scale dark matter dynamics. At the same time, it can be seen as a possible mechanism behind the interacting cosmologies. We study the non-linear spherical "top-hat" collapse of dark matter which undergoes velocity diffusion into a solvent dark energy field. We show constraints on the maximum magnitude allowed for the dark matter diffusion. Our results reinforce previous analysis concerning the linear perturbation theory.