Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Jamming Transition in Granular Systems   Recent simulations have predicted that near jamming for collections of
spherical particles, there will be a discontinuous increase in the mean contact
number, Z, at a critical volume fraction, phi_c. Above phi_c, Z and the
pressure, P are predicted to increase as power laws in phi-phi_c. In
experiments using photoelastic disks we corroborate a rapid increase in Z at
phi_c and power-law behavior above phi_c for Z and P. Specifically we find
power-law increase as a function of phi-phi_c for Z-Z_c with an exponent beta
around 0.5, and for P with an exponent psi around 1.1. These exponents are in
good agreement with simulations. We also find reasonable agreement with a
recent mean-field theory for frictionless particles.

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The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
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The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: stat
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The categories of this paper are: astro-ph
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The categories of this paper are: eess
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The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
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The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
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The categories of this paper are: adap-org