Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Next-to-Leading Order Transport Coefficients from the Four-Particle
  Irreducible Effective Action   Transport coefficients can be obtained from 2-point correlators using the
Kubo formulae. It has been shown that the full leading order result for
electrical conductivity and (QCD) shear viscosity is contained in the re-summed
2-point function that is obtained from the 3-loop 3PI re-summed effective
action. The theory produces all leading order contributions without the
necessity for power counting, and in this sense it provides a natural framework
for the calculation. In this article we study the 4-loop 4PI effective action
for a scalar theory with cubic and quartic interactions in the presence of
spontaneous symmetry breaking. We obtain a set of integral equations that
determine the re-summed 2-point vertex function. A next-to-leading order
contribution to the viscosity could be obtained from this set of coupled
equations.

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The categories of this paper are: hep-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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The categories of this paper are: acc-phys
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The categories of this paper are: cond-mat
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The categories of this paper are: nlin
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The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: cs
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The categories of this paper are: q-bio
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The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: stat
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg