54. Heidelberger Physik Graduiertentage

Magnetic fields are observed across virtually all length scales of the modern Universe, from planets and stars to galaxies and galaxy clusters. Beyond being a phenomenon to explain, magnetic fields play an active role in the dynamics of various astrophysical plasmas: for example, they control solar activity and thereby space weather, they impact the formation of stars within the interstellar medium of galaxies, and they guide the propagation of cosmic rays. Astrophysical magnetic fields are believed to be amplified and sustained by so-called magnetohydrodynamical dynamos. Generally, these are mechanisms that convert kinetic energy from large-scale flows and turbulent motions into magnetic energy. This course introduces the methods for modeling magnetohydrodynamical dynamos. It starts with an introduction to (magneto-)hydrodynamics and turbulence. Then, astrophysical and cosmological magnetogenesis will be discussed. Finally, the focus shifts to modeling dynamos with mean-field theory. The results of dynamo theory will be confronted with predictions from state-of-the-art numerical simulations and the latest observations of cosmic magnetic fields.