How a certain form of dark matter may lead to the generation of cosmological magnetic fields

Tiny highly uniform magnetic fields are known to pervade the universe, influencing various cosmological processes. To date, however, the physical mechanisms underpinning the generation of these fields remain poorly understood. Recently, researchers at McGill University and ETH Zurich have described a novel mechanism that may lead to the generation of cosmological magnetic fields. This mechanism, outlined in a paper published in Physical Review Letters, involves a (pseudo-scalar) quantum field that may give rise to the existence of ultralight dark matter consisting of particles with extremely low mass that interact with ordinary matter only very weakly.