The Magnetic Universe through vector potential SPMHD simulations

The use of Smoothed Particle Magneto Hydrodynamics (SPHMHD) is getting nowadays more and more common in Astrophysics. From galaxy clusters to neutron starts, there are multiple applications already existing in the literature. I will review some of the common methods used and highlight the successful approach of using vector potentials to describe the evolution of the magnetic fields. The latter have some interesting advantages, and their results challenge previous findings, being the magnetic divergence problem naturally vanished. We select a few examples to discuss some areas of interest. First, we show some Galaxy Clusters from the MUSIC project. These cosmological simulations are done with the usual sub-grid recipes, as radiative cooling and star formation, being the first ones obtained with an SPH code in a self consistent way. Second, we show the evolution of an isolated galaxy. We show the importance of a good integration of the magnetic field evolution and the difference with previous implementations. Particularly, now we are able to determine the dynamo numbers that are predicted from the kinematic evolution of the magnetic field. Finally, we show the evolution of the accretion disk around a binary black hole system, allowing us to find observational features that are only possible when considering the models with magnetic fields. This showcase demonstrates the robustness of the new method in a variety of astrophysical scenarios.