New model explains the origin of magnetic fields

An unprecedented model to explain the origin and amplification of magnetic fields up to current levels was recently published in the journal Physical Review Letters by a team of researchers from the Institute of Plasmas and Nuclear Fusion at the Instituto Superior Técnico.

Today's universe is permeated by magnetic fields, but it is widely accepted that they did not exist in the primordial universe. This study, funded by FCT, demonstrates, through numerical simulations on supercomputers, that the existence of spatial variations in density and temperature compatible with those existing at the beginning of the universe may have led to the creation of "seed magnetic fields", potentially responsible for their amplification.

The most plausible justification for the amplification of magnetic fields is the turbulent dynamo effect. According to this model, a "seed magnetic field" well amalgamated by the dynamo effect leads to the creation of a significant magnetic field.

Kevin Schoeffler, a researcher on the project, believes that "these results represent a significant advance on previous models, in which the value of this seed field was too small for the action of the turbulent dynamo to be fast enough to allow it to grow. In our scenario, which represents a new paradigm for magnetogenesis, it is predicted that the magnetic seed fields could be several orders of magnitude more intense."