Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lorentz gauge and Green's formula in classical electrodynamics   We dicuss the resolution of initial value problems of electrodynamics in the
Lorentz gauge.

25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph