Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Variational symmetries and conservation laws of the wave equation in one
  space dimension   The direct method based on the definition of conserved currents of a system
of differential equations is applied to compute the space of conservation laws
of the (1+1)-dimensional wave equation in the light-cone coordinates. Then
Noether's theorem yields the space of variational symmetries of the
corresponding functional. The results are also presented for the standard
space-time form of the wave equation.

32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph