  A system of light axions comprising a classical axion field, one candidate
for dark matter, has an instability that would rapidly mix in photon pairs in a
coherent fashion if the system were initially seeded by some tiny amount of
such mixing. We develop equations that contain the mixing and at the same time
incorporate enough quantum mechanics to eliminate the need for seeds. Extending
to many modes brings many interesting issues to the fore. For example, the
argument of the inevitable logarithmic factor in the mixing time becomes
reduced by many orders of magnitude; concerns concerning red-shifts are laid to
rest, as are those related to lumpiness of the original axion state. We further
see that even the fully developed states of the electromagnetic field are
completely non-classical in our solutions.
