Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fermions, Skyrmions and the 3-Sphere   This paper investigates a background charge one Skyrme field chirally coupled
to light fermions on the 3-sphere. The Dirac equation for the system commutes
with a generalised angular momentum or grand spin. It can be solved explicitly
for a Skyrme configuration given by the hedgehog form. The energy spectrum and
degeneracies are derived for all values of the grand spin. Solutions for
non-zero grand spin are each characterised by a set of four polynomials. The
paper also discusses the energy of the Dirac sea using zeta function
regularization.

3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
21
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: gr-qc
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an