Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Topological contributions in two-dimensional Yang-Mills theory: from
  group averages to integration over algebras   We show that keeping only the topologically trivial contribution to the
average of a class function on U(N) amounts to integrating over its algebra.
The goal is reached first by decompactifying an expansion over the instanton
basis and then directly, by means of a geometrical procedure.

32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio