Kinetic theory of Jean Instability in Eddington-inspired Born-Infield gravity

Abstract

We analyze the stability of self-gravitating systems which dynamics is investigated using the collisionless Boltzmann equation, and the modified Poisson equation of Eddington-inspired Born-Infield gravity. These equations provide a description of the Jeans paradigm used to determine the critical scale above which such systems collapse. At equilibrium, the systems are described using the time-independent Maxwell- Boltzmann distribution function $f_0(v)$. Considering small perturbations to this equilibrium state, we obtain a modified dispersion relation, and we find a new characteristic scale length. Our results indicate that the dynamics of the self-gravitating astrophysical systems can be fully addressed in the Eddington-inspired Born-Infield gravity. The latter modifies the Jeans instability in high densities environments while its effects become negligible in the star formation regions.