Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Amplitudes, Gravity and Classical Discontinuities   On-shell methods have revitalized interest in scattering amplitudes which
have, in turn, shed some much needed light on the structure of quantum field
theories. These developments have been warmly embraced by the particle physics
community. Less so in the astrophyical and cosmological contexts. As part of an
effort to address this imbalance, we illustrate these methods by revisiting two
classic problems in gravity: gravitational light-bending and the vDVZ
discontinuity of massive gravity.

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The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
16
The categories of this paper are: stat
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
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The categories of this paper are: astro-ph
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The categories of this paper are: supr-con
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The categories of this paper are: math
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The categories of this paper are: bayes-an
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
34
The categories of this paper are: chem-ph