Axion-induced effects in atoms, molecules and nuclei: Parity
  nonconservation, anapole moments, electric dipole moments, and spin-gravity
  and spin-axion momentum couplings
  We show that the interaction of an axion field, or in general a pseudoscalar
field, with the axial-vector current generated by an electron through a
derivative-type coupling can give rise to a time-dependent mixing of
opposite-parity states in atomic and molecular systems. Likewise, the analogous
interaction of an axion field with the axial-vector current generated by a
nucleon can give rise to time-dependent mixing of opposite-parity states in
nuclear systems. This mixing can induce oscillating electric dipole moments,
oscillating parity non-conservation effects and oscillating anapole moments in
such systems. By adjusting the energy separation between the opposite-parity
states of interest to match the axion mass energy, axion-induced experimental
observables can be enhanced by many orders of magnitude. Oscillating atomic
electric dipole moments can also be generated by axions through hadronic
mechanisms, namely the P,T-violating nucleon-nucleon interaction and through
the axion-induced electric dipole moments of valence nucleons, which comprise
the nuclei. The axion field is modified by the Earth's gravitational field. The
interaction of the spin of either an electron or nucleon with this modified
axion field leads to axion-induced observable effects. These effects, which are
of the form $\mathbf{g} \cdot \mathbf{\sigma}$, differ from the axion-wind
effect, which has the form $\mathbf{p}_{\textrm{a}} \cdot \mathbf{\sigma}$.
