Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analysis of some exact properties of the nonlinear equation of the
  Schrodinger describing the process of filamentation   The properties of the integral of motion and the evolution of the effective
radius of the light beam are analyzed in the framework of the stationary model
of the nonlinear Schrodinger equation describing filamentation. Within the
framework of such a model, it is shown that filamentation is limited only by
dissipative mechanisms.

10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
9
The categories of this paper are: nlin