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arXiv · 1608.07869

Divergence of the Chapman-Enskog expansion in relativistic kinetic theory

Gabriel S. Denicol·Jorge Noronha
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Abstract

In this letter we show for the first time that the relativistic Chapman-Enskog series for a massless gas undergoing Bjorken expansion diverges. In order to fix this problem, we propose a novel type of expansion that includes non-perturbative contributions in the Knudsen number that are not considered in Chapman-Enskog theory. This approach is in good agreement with exact solutions of the Boltzmann equation for a wide range of values of Knudsen number and does not display the clear signs of divergence exhibited by the Chapman-Enskog series.

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Gabriel S. Denicol, Jorge Noronha. 2016-08-29. Divergence of the Chapman-Enskog expansion in relativistic kinetic theory. https://arxiv.org/abs/1608.07869

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