Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two-Fermion Bound and Scattering States in a Finite Volume including QED
  in P-Wave and Beyond   Introducing a short range force coupling the spinless fermions to one unit of
angular momentum in the framework of pionless EFT, we first report the two-body
scattering amplitudes with Coulomb corrections, extended to two fermions of
opposite charge in refs. [1,2]. Motivated by the growing interest in lattice
approaches, we immerse the system into a cubic box with periodic boundary
conditions and display the finite-volume corrections to the energy of the
lowest bound and unbound $T_1^{-}$ eigenstates. The latter turn out to consist
of power law terms proportional to the fine-structure constant. In the
calculations, quadratic and higher order contributions in $\alpha$ are
discarded, on the grounds that the gapped nature of the momentum operator in
the finite-volume environment allows for a perturbative treatment of the QED
interactions. An outlook on the extension of the analysis to D-wave short-range
interactions is eventually given.

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The categories of this paper are: physics
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The categories of this paper are: atom-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: q-bio
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The categories of this paper are: gr-qc
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The categories of this paper are: chao-dyn
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The categories of this paper are: cmp-lg
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The categories of this paper are: chem-ph
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The categories of this paper are: funct-an
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The categories of this paper are: stat
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The categories of this paper are: econ
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The categories of this paper are: hep-th
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
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The categories of this paper are: math-ph