https://doi.org/10.1140/epjc/s10052-019-6965-3
Regular Article - Theoretical Physics
Using kinetic theory to examine a self-gravitating system composed of baryons and cold dark matter
1
Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19044, Curitiba, 81531-990, Brazil
2
PPGCosmo, CCE - Universidade Federal do Espírito Santo, Vitória, ES, 29075-910, Brazil
3
Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria 1428, Pabellón I, Buenos Aires, Argentina
* e-mail: martin@df.uba.ar
Received:
21
March
2019
Accepted:
17
May
2019
Published online:
12
June
2019
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.
© The Author(s), 2019