Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The onset of fluid-dynamical behavior in relativistic kinetic theory   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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The categories of this paper are: eess
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The categories of this paper are: math-ph
3
The categories of this paper are: physics
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The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: q-bio
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The categories of this paper are: alg-geom
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: supr-con
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: comp-gas
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The categories of this paper are: astro-ph