Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bose-Einstein condensation in a hyperbolic model for the Kompaneets
  equation   In low-density or high-temperature plasmas, Compton scattering is the
dominant process responsible for energy transport. Kompaneets in 1957 derived a
non-linear degenerate parabolic equation for the photon energy distribution. In
this paper we consider a simplified model obtained by neglecting diffusion of
the photon number density in a particular way. We obtain a non-linear
hyperbolic PDE with a position-dependent flux, which permits a one-parameter
family of stationary entropy solutions to exist. We completely describe the
long-time dynamics of each non-zero solution, showing that it approaches some
non-zero stationary solution. While the total number of photons is formally
conserved, if initially large enough it necessarily decreases after finite time
through an out-flux of photons with zero energy. This corresponds to formation
of a Bose-Einstein condensate, whose mass we show can only increase with time.

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The categories of this paper are: physics
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
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The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
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The categories of this paper are: stat
8
The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: math-ph
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org