Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: QED amplitudes: recurrence relations to all orders   We describe the origins of recurrence relations between field theory
amplitudes in terms of the construction of Feynman diagrams. In application we
derive recurrence relations for the amplitudes of QED which hold to all loop
orders and for all combinations of external particles. These results may also
be derived from the Schwinger-Dyson equations.

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The categories of this paper are: comp-gas
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The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: physics
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The categories of this paper are: hep-lat
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The categories of this paper are: adap-org
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The categories of this paper are: econ
6
The categories of this paper are: astro-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-ex
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The categories of this paper are: supr-con
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The categories of this paper are: chem-ph
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga