Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Simulation of granular jet: Is granular flow really a "perfect fluid?"   We perform three-dimensional simulations of a granular jet impact for both
frictional and frictionless grains. Small shear stress observed in the
experiment[X. Cheng et al., Phys. Rev. Lett. 99, 188001 (2007) ] is reproduced
through our simulation. However, the fluid state after the impact is far from a
perfect fluid, and thus, similarity between granular jets and quark gluon
plasma is superficial, because the observed viscosity is finite and its value
is consistent with the prediction of the kinetic theory.

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The categories of this paper are: hep-ph
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-th
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The categories of this paper are: hep-lat