Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Elasticity of a polydisperse hard-sphere crystal   A general Monte Carlo simulation method of calculating the elastic constants
of polydisperse hard-sphere colloidal crystal was developed. The elastic
constants of a size polydisperse hard sphere fcc crystal is calculated. The
pressure and three elastic constants(C11, C12 and C44) increase significantly
with the polydispersity. It was also found from extrapolation that there is a
mechanical terminal polydispersity above which a fcc crystal will be
mechanically unstable.

19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph