Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Maxwell electromagnetic theory from a viewpoint of differential forms   In this paper, we discuss the Maxwell equations in terms of differential
forms, both in the 3-dimensional space and in the 4-dimensional space-time
manifold. Further, we view the classical electrodynamics as the curvature of a
line bundle, and fit it into gauge theory.

21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom