Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hadronic structure on the light-front I.\ Instanton effects and
  quark-antiquark effective potentials   This is the first of a sequence of papers that address the non-perturbative
origin of the central, and spin-dependent forces between quarks. Its main
thrust is a focus on meson spectroscopy in the center of mass frame. We suggest
a "dense instanton ensemble" model for the QCD vacuum, to explain the
interquark forces in mesons, from quarkonia to heavy-light and light-light
ones, to the extent it is possible. The sequels will show how to export these
interactions to the light front, and derive the corresponding Hamiltonians and
mesonic wavefunctions.

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The categories of this paper are: econ
34
The categories of this paper are: chem-ph
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The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
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The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
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The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
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The categories of this paper are: eess
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The categories of this paper are: adap-org