Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The old and the new of parity-violating two-pion-exchange $NN$ potential   We consider the parity-violating two-pion-exchange potential obtained from
the covariant formalism in the past and the state-of-the-art effective field
theory approach. We discuss the behavior of the potential in coordinate space
and its application to the parity-violating asymmetry in $\vec{n} p \to d
\gamma$ at threshold.

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The categories of this paper are: stat
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The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
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The categories of this paper are: math-ph
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The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: hep-th
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The categories of this paper are: cs
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
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The categories of this paper are: mtrl-th