Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Further Investigation on Chiral Symmetry Breaking in a Uniform External
  Magnetic Field   We study chiral symmetry breaking in QED when a uniform external magnetic
field is present. We calculate higher order corrections to the dynamically
generated fermion mass and find them to be small. In so doing we correct an
error in the literature regarding the matrix structure of the fermion
self-energy.

36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an