Wednesday, January 25, 2017
The universe is magnetized: from galaxies and galaxy clusters to the solar system, including of course the Sun and our own planet, magnetic fields are found everywhere we care to look. It is reasonably well established that magnetic fields were not created in the Big Bang, so a question naturally arises as to where they come from. Understanding cosmic magnetogenesis, as the problem is usually called, is plasma physics at its very best, involving a rather complex interplay of battery-like effects, instabilities at the electron and ion scales, turbulent amplification (dynamo), and magnetic reconnection to enable magnetic-field topology change. This lecture will aim to describe these processes at an introductory level, and their role in magnetic field generation, amplification and dynamics.