Physics Colloquium

Our universe is immersed in magnetized plasma, electrically conducting ionized gas. Some of the most fundamental and long-standing astrophysical problems, such as the magnetization of the universe, collimation of astrophysical jets, the accretion process and transport in astrophysical disks (surrounding e.g. black holes) and their coronas can only be explored through plasma physics. Our sun as a natural laboratory for plasma physics provides inspiring as well as challenging problems, including its dynamo cycles, heating, and the replication of its core reaction, fusion energy, on earth in a lab. There is an abundance of observational/experimental data emerging from natural phenomena of space and astrophysical plasmas, as well as laboratory plasma experiments, for plasma physicists to explore. I will review some of these topics, in particular magnetic reconnection, the rearrangement of the magnetic ?field topology of plasmas, which energizes many processes in nature and has been shown to also be critical in the nonlinear dynamics of many processes in toroidal fusion plasmas. Using global simulations, I will demonstrate the instrumental role of magnetic reconnection, which enables an innovative technique for producing current in fusion plasmas.