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arXiv · 2204.02834

Long-term relaxation of ${1D}$ self-gravitating systems

Mathieu Roule·Jean-Baptiste Fouvry·Christophe Pichon·Pierre-Henri Chavanis
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Abstract

We investigate the long-term relaxation of one-dimensional (${1D}$) self-gravitating systems, using both kinetic theory and $N$-body simulations. We consider thermal and Plummer equilibria, with and without collective effects. All combinations are found to be in clear agreement with respect to the Balescu-Lenard and Landau predictions for the diffusion coefficients. Interestingly, collective effects reduce the diffusion by a factor ${\sim 10}$. The predicted flux for Plummer equilibrium matches the measured one, which is a remarkable validation of kinetic theory. We also report on a situation of quasi kinetic blocking for the same equilibrium.

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Mathieu Roule, Jean-Baptiste Fouvry, Christophe Pichon, Pierre-Henri Chavanis. 2022-04-06. Long-term relaxation of ${1D}$ self-gravitating systems. https://doi.org/10.1103/physreve.106.044118

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