Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Generalized fluid dynamics and the boundary condition   We present the general formulation of the relativistic fluid dynamics with
vorticity (including relativistic superfluid) on a manifold with boundary.
Making use of the Hodge decomposition, we emphasize that the equations of
motion include a term due to non-trivial topology, while the pure vortex term
introduced by Carter and Langlois will be presented merely by a co-exact form.
We also consider a vortex sheet combined of individual vortices and discuss the
boundary problem.

11
The categories of this paper are: hep-lat
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The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
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The categories of this paper are: astro-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: nlin
30
The categories of this paper are: q-alg
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: math-ph