Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Solution of Master Equations for the anharmonic oscillator interacting
  with a heat bath and for parametric down conversion process   We solve analytically master equations that describe a cavity filled with a
kerr medium, taking into account the dissipation induced by the environment,
and parametric down conversion processes. We use superoperator techniques.

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The categories of this paper are: nucl-ex
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The categories of this paper are: mtrl-th
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The categories of this paper are: ao-sci
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The categories of this paper are: chao-dyn
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The categories of this paper are: gr-qc
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The categories of this paper are: stat
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The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
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The categories of this paper are: patt-sol
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The categories of this paper are: dg-ga
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The categories of this paper are: eess
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph