Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ultra-short Pulse Propagation in Nonlinear Optics   In this work, we perform a detailed review about the theoretical modeling of
the optical propagation of ultra-short pulses in different scenarios of
nonlinear optics. In particular, we focus our efforts on optical fibers and
uniform media, with special attention on the white light continuum generation
by using gases.

16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph