Analysis of Jeans instability from the Boltzmann equation

Abstract

The dynamics of self-gravitating fluids is analyzed within the framework of a collisionless Boltzmann equation in the presence of gravitational fields and Poisson equation. Two cases are analyzed: a system with baryonic and dark matter in a static universe and a single system in an expanding universe. The amplitudes of the perturbed distribution functions are considered as a linear combination of the collision invariants of the Boltzmann equation. For the system of baryonic and dark matter, the Jeans mass of the combined system is smaller than the one of the single system indicating that a smaller mass is needed to initiate the collapse. For the single system in an expanding universe it is not necessary to make use of Jeans "swindle"and it shown that for small wavelengths the density contrast oscillates while for large wavelengths it grows with time and the Jeans instability emerges.

10 pages, 1 figure, new analysis

References in corpus (3)

• Jeans analysis of self-gravitating systems in f(R)-gravity
• Analysis of instability of systems composed by dark and baryonic matter
• Collisionless self-gravitating systems in f(R)-gravity within Palatini approach and relativistic Boltzmann equation in the Newtonian approach

Cited by in corpus (5)

• Jeans Instability in a Universe with Dissipation
• Using kinetic theory to examine a self-gravitating system composed of baryons and cold dark matter
• Jeans instability in an expanding universe with dissipation
• Jeans instability for an inert binary mixture: a kinetic theory approach in the Euler regime
• Jeans Instability from post-Newtonian Boltzmann equation