Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Self-Duality and Maximally Helicity Violating QCD Amplitudes   I review some recent work that describes the close analogy between self-dual
Yang--Mills amplitudes and QCD amplitudes with external gluons of positive
helicity. This analogy is carried at tree level for amplitudes with two
external quarks and up to one-loop for amplitudes involving only external
gluons.

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The categories of this paper are: comp-gas
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The categories of this paper are: mtrl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
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The categories of this paper are: q-alg
3
The categories of this paper are: physics
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The categories of this paper are: adap-org
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The categories of this paper are: dg-ga
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The categories of this paper are: nlin
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The categories of this paper are: cs
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The categories of this paper are: solv-int
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The categories of this paper are: ao-sci
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph