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arXiv · 2108.03885

Jeans Instability from post-Newtonian Boltzmann equation

Gilberto M. Kremer
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Abstract

Jeans instability within the framework of post-Newtonian Boltzmann and Poisson equations are analyzed. The components of the energy-momentum tensor are calculated from a post-Newtonian Maxwell-J\"uttner distribution function. The perturbations of the distribution function and gravitational potentials from their background states with the representation of the perturbations as plane waves lead to a dispersion relation with post-Newtonian corrections. The influence of the post-Newtonian approximation on the Jeans mass is determined and it was shown that the mass necessary for an overdensity to begin the gravitational collapse in the post-Newtonian theory is smaller than the one in the Newtonian theory.

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Gilberto M. Kremer. 2021-08-09. Jeans Instability from post-Newtonian Boltzmann equation. https://doi.org/10.1140/epjc%2Fs10052-021-09728-y

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