Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Perturbative QCD Potential and the ttbar Threshold   We include the full second-order corrections to the static QCD potential in
the analysis of the ttbar threshold cross section. There is an unexpectedly
large difference between the QCD potential improved by the
renormalization-group equation in momentum space and the potential improved by
the renormalization-group equation in coordinate space. This difference remains
even at a fairly short distance 1/r \simeq 100 GeV and its origin can be
understood within perturbative QCD. We scrutinize the theoretical uncertainties
of the QCD potential in relation to the ttbar threshold cross section. In
particular there exists a theoretical uncertainty which limits our present
theoretical accuracy of the ttbar threshold cross section at the peak to be not
better than 6% within perturbative QCD.

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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
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The categories of this paper are: hep-lat
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-th
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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: nlin
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The categories of this paper are: physics
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The categories of this paper are: chao-dyn
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The categories of this paper are: cs
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The categories of this paper are: gr-qc
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The categories of this paper are: alg-geom
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The categories of this paper are: dg-ga