Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Diffusion and Velocity Auto-Correlation in Shearing Granular Media   We perform numerical simulations to examine particle diffusion at steady
shear in a model granular material in two dimensions at the jamming density and
zero temperature. We confirm findings by others that the diffusion constant
depends on shear rate as $D\sim\dot\gamma^{q_D}$ with $q_D<1$, and set out to
determine a relation between $q_D$ and other exponents that characterize the
jamming transition. We then examine the the velocity auto-correlation function,
note that it is governed by two processes with different time scales, and
identify a new fundamental exponent, $\lambda$, that characterizes an algebraic
decay of correlations with time.

23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex