Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Onsager-Symmetry Obeyed in Athermal Mesoscopic Systems: Two-Phase Flow
  in Porous Media   We compute the fluid flow time-correlation functions of incompressible,
immiscible two-phase flow in porous media using a 2D network model. Given a
properly chosen representative elementary volume, the flow rate distributions
are Gaussian and the integrals of time correlation functions of the flows are
found to converge to a finite value. The integrated cross-correlations become
symmetric, obeying Onsager's reciprocal relations. These findings support the
proposal of a non-equilibrium thermodynamic description for two-phase flow in
porous media.

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The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
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The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph