Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Heisenberg-Euler Effective Action: 75 years on   On this 75th anniversary of the publication of the Heisenberg-Euler paper on
the full non-perturbative one-loop effective action for quantum electrodynamics
I review their paper and discuss some of the impact it has had on quantum field
theory.

4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
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
17
The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin