Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coagulation-fragmentation model for animal group-size statistics   We study coagulation-fragmentation equations inspired by a simple model
proposed in fisheries science to explain data for the size distribution of
schools of pelagic fish. Although the equations lack detailed balance and admit
no $H$-theorem, we are able to develop a rather complete description of
equilibrium profiles and large-time behavior, based on recent developments in
complex function theory for Bernstein and Pick functions. In the
large-population continuum limit, a scaling-invariant regime is reached in
which all equilibria are determined by a single scaling profile. This universal
profile exhibits power-law behavior crossing over from exponent $-\frac23$ for
small size to $-\frac32$ for large size, with an exponential cut-off.

24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci