Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nucleon Structure Functions and Light-Front Dynamics   We present a quark-parton model to describe polarized and unpolarized nucleon
structure functions. The twist-two matrix elements for the QCD evolution
analysis of lepton-hadron scattering are calculated within a light-front
covariant quark model. The relativistic effects in the three-body wave function
are discussed for both the polarized and unpolarized cases. Predictions are
given for the polarized gluon distributions as will be seen in future
experiments.

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The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
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The categories of this paper are: alg-geom
1
The categories of this paper are: cs
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: nlin
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The categories of this paper are: funct-an
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The categories of this paper are: bayes-an
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The categories of this paper are: mtrl-th
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The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg