Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Hadrodynamics: Evolution and Revolution   The underlying philosophy and motivation for quantum hadrodynamics (QHD),
namely, relativistic field theories of nuclear phenomena featuring manifest
covariance, have evolved over the last quarter century in response to
successes, failures, and sharp criticisms. A recent revolution in QHD, based on
modern effective field theory and density functional theory perspectives,
explains the successes, provides antidotes to the failures, rebuts the
criticisms, and focuses the arguments in favor of a covariant representation.

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The categories of this paper are: quant-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: stat
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The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
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The categories of this paper are: q-alg
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The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: eess
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: comp-gas