Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Isostaticity and Mechanical Response of Two-Dimensional Granular Piles   We numerically study the static structure and the mechanical response of
two-dimensional granular piles. The piles consist of polydisperse disks with
and without friction. Special attention is paid for the rigid grain limit by
examining the systems with various disk elasticities. It is shown that the
static pile structure of frictionless disks becomes isostatic in the rigid
limit, while the isostaticity of frictional pile depends on the pile forming
procedure, but in the case of the infinite friction is effective, the structure
becomes very close to isostatic in the rigid limit. The mechanical response of
the piles are studied by infinitesimally displacing one of the disks at the
bottom. It is shown that the total amount of the displacement in the pile
caused by the perturbation diverges in the case of frictionless pile as it
becomes isostatic, while the response remains finite for the frictional pile.
In the frictionless isostatic pile, the displacement response in each sample
behaves rather complicated way, but its average shows wave like propagation.

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The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
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The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
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The categories of this paper are: q-fin
37
The categories of this paper are: supr-con