How dark matter oscillations could secretly amplify electromagnetic fields

Physicists modeled what happens when a non-Abelian dark matter condensate oscillates in the presence of electromagnetic fields coupled only indirectly through a pseudoscalar intermediary. The oscillating dark matter drives the intermediary field, which then modulates electromagnetic wave frequencies and triggers parametric resonance—a situation described by Mathieu equations familiar from classical mechanics. Surprisingly, in the perfectly periodic regime, both electromagnetic polarizations grow identically rather than preferring one helicity, overturning a naive expectation about chirality.