Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pair dispersion in turbulence   We study the statistics of pair dispersion in two-dimensional turbulence.
Direct numerical simulations show that the pdf of pair separations is in
agreement with the Richardson prediction. The pdf of doubling times follows
dimensional scaling and shows a long tail which is the signature of close
approaches between particles initially seeded with a large separation. This
phenomenon is related to the formation of fronts in passive scalar advection.

18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math