Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the discrete Dirac spectrum of a point electron in the zero-gravity
  Kerr-Newman spacetime   The discrete spectrum of the Dirac operator for a point electron in the
maximal analytically extended Kerr--Newman spacetime is determined in the
zero-$G$ limit (z$G$KN), under some restrictions on the electrical coupling
constant and on the radius of the ring-singularity of the z$G$KN spacetime. The
spectrum is characterized by a triplet of integers, associated with winding
numbers of orbits of dynamical systems on cylinders. A dictionary is
established that relates the spectrum with the known hydrogenic Dirac spectrum.
Numerical illustrations are presented. Open problems are listed.

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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: nucl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: nlin
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The categories of this paper are: adap-org
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The categories of this paper are: hep-th
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The categories of this paper are: funct-an
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The categories of this paper are: mtrl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: supr-con
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The categories of this paper are: q-alg
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The categories of this paper are: eess
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The categories of this paper are: q-bio
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The categories of this paper are: econ