Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On exact solutions to quantum N=2 gauge theories   Exact solutions to the low-energy effective action of the four-dimensional,
N=2 supersymmetric gauge theories with matter (including N=2 super-QCD) are
discussed from the three different viewpoints: (i) instanton calculus, (ii) N=2
harmonic superspace, and (iii) M theory. The emphasis is made on the
foundations of all three approaches and their relationship.

22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con