Dr. Ellen Zweibel
Wisconsin

University of Florida Astronomy Colloquium - Feb. 20, 2008

The Origin and Evolution of Magnetic Fields

Despite enormous recent progress in cosmology, the origin of magnetic fields is still unknown, and their evolution is not yet understood. I will review direct and indirect evidence that significant magnetic fields were present by the time the oldest stars in the galactic halo formed, and discuss the operation of dynamos in contemporary galaxies and in the past.