Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The heat flux from a relativistic kinetic equation with a simplified
  collision kernel   We show how using a special relativistic kinetic equation with a BGK- like
collision operator the ensuing expression for the heat flux can be casted in
the form required by Classical Irreversible Thermodynamics. Indeed, it is
linearly related to the temperature and number density gradients and not to the
acceleration as the so-called "first order in the gradients theories" contend.
Here we calculate explicitly the ensuing transport coefficients and compare
them with the results obtained by other authors.

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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
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The categories of this paper are: math
3
The categories of this paper are: physics
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: adap-org
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The categories of this paper are: chem-ph
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-fin
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The categories of this paper are: alg-geom
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The categories of this paper are: econ
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The categories of this paper are: q-alg