Using kinetic theory to examine a self-gravitating system composed of baryons and cold dark matter

2019/06/01 by Gilberto M. Kremer, Martín G. Richarte, Elberth M. Schiefer +1
Physics and Astronomy · #Astronomy #Astrophysics #Baryon #Classical mechanics #Cold dark matter #Cosmology #Cosmology and Gravitation Theories #Dark energy #Dark fluid #Dark matter #Galaxies: Formation, Evolution, Phenomena #Kinetic energy #Perturbation (astronomy) #Physics #Pulsars and Gravitational Waves Research #astro-ph.CO #astro-ph.GA #gr-qc

paper · pdf · doi:10.1140/epjc/s10052-019-6965-3

published as Eur. Phys. J. C (2019) 79: 492 · 11 pages, 4 figures

openalex publication_date 2019/06/01 · arxiv created 2020/06/18 · arxiv updated 2020/06/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We examine the evolution of non-relativistic cold dark matter gravitationally coupled to baryons with modes deep inside the Hubble radius (sub-horizon regime) using a kinetic theory approach within the realm of Newtonian theory. We obtain the general solution for the total density perturbation and we also show that a baryon perturbation catches up with the dark matter perturbation at late times, which in turn makes possible the formation of bound structures. We extend the linear perturbation analysis by considering the turn-around event, collapse of matter, and its virialization process.

Citations

• Jeans instability in classical and modified gravity
• Dark matter direct detection signals inferred from a cosmological N-body simulation with baryons
• Effects of cold dark matter decoupling and pair annihilation on cosmological perturbations
• Possible interaction between baryons and dark-matter particles revealed by the first stars
• An absorption profile centred at 78 megahertz in the sky-averaged spectrum
• Interacting dark energy: possible explanation for 21-cm absorption at cosmic dawn
• Big-Bang Nucleosynthesis