Dynamics of pulsational mode in the EiBI gravity fabric

Abstract

We systematically theorise a model formalism to investigate the linear pulsational mode dynamics excitable in self-gravitating dust molecular clouds (DMCs) in the framework of the Eddington-inspired Born-Infeld (EiBI) gravity. The adopted spherical DMC consists of thermalized lighter (non-inertial) electrons and ions, both treated analogously as the Boltzmann species, whereas the partially ionised heavier (inertial) dust grains as the constitutive neutral and charged dust fluids. The model closure comes from the coupling gravito-electrostatic Poisson equations governing the resultant potential distributions sourced in the material and charge density fields. Application of spherical normal mode (Fourier-based) analysis transforms the model DMC into a quartic linear dispersion relation with diverse atypical multi-parametric dispersion coefficients. A numerical platform is constructed for an illustrative dispersion analysis. It shows that the positive EiBI parameter, dust charge number, and cloud size act as stabilizing agents against the inward non-local self-gravity. In contrast, a negative EiBI parameter, dust mass, and equilibrium dust population density play destabilizing roles. The modal propagatory and oscillatory features are portrayed graphically and interpreted elaborately. The reliability of our calculation scheme is validated in light of the closely related results previously reported in the literature. The analyses presented here could be relevant in the context of understanding astrophysical structure formation dynamics through the self-gravitational canonical condensation processes in diverse real astronomic environs.