The universe is filled with magnetic fields. However, it is widely accepted that in the early universe they did not exist. An important scientific question is how these magnetic fields could have grown from nothing to the level we find them today. epp team members, Ricardo Fonseca and Luís O. Silva, collaborated with  Kevin Schoeffler, and Nuno Loureiro on a paper published in Physical Review Letters addressing this issue. They demonstrate using first principle simulations how magnetic fields are formed by only gradients in the pressure and density. This generation of magnetic fields also plays an important role in many high power laser experiments, which generate magnetic fields on the order of megagauss. These fields form via both the previously predicted Biermann battery mechanism as well as a kinetic plasma instability known as the Weibel instability, depending on the system parameters. These results should have an important impact on both the understanding of the origin of magnetic fields throughout the universe as well as in laser experiments. More information can be read here.