  Future observations of continuous gravitational waves from single neutron
stars, apart from their monumental astrophysical significance, could also shed
light on fundamental physics and exotic particle states. One such avenue is
based on the fact that magnetic fields cause deformations of a neutron star,
which results in a magnetic-field-induced quadrupole ellipticity. If the
magnetic and rotation axes are different, this quadrupole ellipticity may
generate continuous gravitational waves which may last decades, and may be
observable in current or future detectors. Light, milli-magnetic monopoles, if
they exist, could be pair-produced non-perturbatively in the extreme magnetic
fields of neutron stars, such as magnetars. This non-perturbative production
furnishes a new, direct dissipative mechanism for the neutron star magnetic
fields. Through their consequent effect on the magnetic-field-induced
quadrupole ellipticity, they may then potentially leave imprints in the early
stage continuous gravitational wave emissions. We speculate on this possibility
in the present study, by considering some of the relevant physics and taking a
very simplified toy model of a magnetar as the prototypical system. Preliminary
indications are that new-born millisecond magnetars could be promising
candidates to look for such imprints. Deviations from conventional evolution,
and comparatively abrupt features in the early stage gravitational waveforms,
distinct from other astrophysical contributions, could be distinguishable
signatures for these exotic monopole states.
