Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Helicity in Superfluids: existence and the classical limit   In addition to mass, energy, and momentum, classical dissipationless flows
conserve helicity, a measure of the topology of the flow. Helicity has
far-reaching consequences for classical flows from Newtonian fluids to plasmas.
Since superfluids flow without dissipation, a fundamental question is whether
such a conserved quantity exists for superfluid flows. We address the existence
of a "superfluid helicity" using an analytical approach based on the the
symmetry underlying classical helicity conservation: the particle relabeling
symmetry. Furthermore, we use numerical simulations to study whether bundles of
superfluid vortices which approximate the structure of a classical vortex,
recover the conservation of classical helicity and find dynamics consistent
with classical vortices in a viscous fluid.

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The categories of this paper are: atom-ph
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The categories of this paper are: funct-an
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The categories of this paper are: q-alg
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The categories of this paper are: stat
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The categories of this paper are: cmp-lg
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: econ
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The categories of this paper are: comp-gas
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The categories of this paper are: acc-phys
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-bio