Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Atoms in the Surf: Molecular Dynamics Simulation of the Kelvin-Helmholtz
  Instability using 9 Billion Atoms   We present a fluid dynamics video showing the results of a 9-billion atom
molecular dynamics simulation of complex fluid flow in molten copper and
aluminum. Starting with an atomically flat interface, a shear is imposed along
the copper-aluminum interface and random atomic fluctuations seed the formation
of vortices. These vortices grow due to the Kelvin-Helmholtz instability. The
resulting vortical structures are beautifully intricate, decorated with
secondary instabilities and complex mixing phenomena. This work performed under
the auspices of the U.S. Department of Energy by Lawrence Livermore National
Laboratory under Contract DE-AC52-07NA27344.

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The categories of this paper are: hep-th
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th