  Dyon loops give a contribution to the matrix element for light-by-light
scattering that violates parity and time-reversal symmetry. This effect induces
an electric dipole moment for the electron, of order $M^{-2}$, where $M$ is the
dyon mass. The current limit on the electric dipole moment of the electron
yields the lower mass bound $M>{\cal O}(1)~\mbox{TeV}$.

High Energy Physics - Phenomenology;Atomic Physics