Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chaos and Thermalization in a Dynamical Model of Two Interacting
  Particles   A quantum dynamical model of two interacting spins, with chaotic and regular
components, is investigated using a finite two-particles symmetrized basis.
Chaotic eigenstates give rise to an equilibrium occupation number distribution
in close agreement with the Bose-Einstein distribution despite the small number
of particles ($n=2$). However, the corresponding temperature differs from that
derived from the standard Canonical Ensemble. On the other side, an acceptable
agreement with the latter is restored by artificially randomizing the model.
Different definitions of temperature are then discussed and compared .

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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph
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The categories of this paper are: eess
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The categories of this paper are: gr-qc
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The categories of this paper are: q-alg
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The categories of this paper are: ao-sci
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The categories of this paper are: cmp-lg
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The categories of this paper are: astro-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: econ