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arXiv · 1704.04976

The onset of fluid-dynamical behavior in relativistic kinetic theory

Jorge Noronha·Gabriel S. Denicol
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Abstract

In this proceedings we discuss recent findings regarding the large order behavior of the Chapman-Enskog expansion in relativistic kinetic theory. It is shown that this series in powers of the Knudsen number has zero radius of convergence in the case of a Bjorken expanding fluid described by the Boltzmann equation in the relaxation time approximation. This divergence stems from the presence of non-hydrodynamic modes, which give non-perturbative contributions to the Knudsen series.

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Jorge Noronha, Gabriel S. Denicol. 2017-04-17. The onset of fluid-dynamical behavior in relativistic kinetic theory. https://doi.org/10.1016/j.nuclphysa.2017.05.041

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