Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two-dimensional QCD, instanton contributions and the perturbative
  Wu-Mandelstam-Leibbrandt prescription   The exact Wilson loop expression for the pure Yang-Mills U(N) theory on a
sphere $S^2$ of radius $R$ exhibits, in the decompactification limit $R\to
\infty$, the expected pure area exponentiation. This behaviour can be
understood as due to the sum over all instanton sectors. If only the zero
instanton sector is considered, in the decompactification limit one exactly
recovers the sum of the perturbative series in which the light-cone gauge
Yang-Mills propagator is prescribed according to Wu-Mandelstam-Leibbrandt. When
instantons are disregarded, no pure area exponentiation occurs, the string
tension is different and, in the large-N limit, confinement is lost.

32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
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The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio