UNC PHYSICS AND ASTRONOMY COLLOQUIUM
Dr. Samuel Gralla, University of Maryland, College Park
“Plasma without Plasma: Exploring Force-free Magnetospheres”
Pulsars have enormous magnetic fields whose energy density dwarfs the rest mass density of their plasma magnetosphere. In this regime of a plasma, the particles drop out of the description, leaving a set of equations for the electromagnetic field alone, known as force-free electrodynamics (FFE). In force-free electrodynamics even *stationary* fields can carry energy away from an isolated source, and force-free plasmas near supermassive black holes likely play a key role in extracting the black hole spin energy to power the observed relativistic jets. I will give a pedagogical introduction to the physics and astrophysics of FFE and then discuss our recent contributions. We have taken a spacetime-geometrical approach, whose power and simplicity I will emphasize.
MONDAY, FEBRUARY 3, 4:00P.M., Rm 265 PHILLIPS HALL

3:30 P.M., speaker reception in Chapman meeting area (3rd floor)
4:00-5:00 P.M., colloquium (room 265)
5:00‐6:00 P.M., meeting with students (room 277)