Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relativistic fluid dynamics of spin-polarized systems of particles   We review basic ingredients of the recently introduced perfect-fluid
hydrodynamic equations for particles with spin one-half. For a quasi-realistic
setup, first numerical solutions for various hydrodynamic variables including
the spin polarization tensor are presented. Our results indicate that the
initial spin polarization of the hottest region may play a dominant role in the
polarization of particles at freeze-out.

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The categories of this paper are: hep-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
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The categories of this paper are: physics
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
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The categories of this paper are: cs
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The categories of this paper are: dg-ga
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The categories of this paper are: comp-gas
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The categories of this paper are: supr-con
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: chao-dyn
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The categories of this paper are: nlin