The Origin and Evolution of Cosmic Magnetism

Gaensler Bryan, bryan.gaensler@sydney.edu.au, The University of Sydney / CAASTRO, Australia

Abstract
A remarkable discovery made by 20th century astronomers was that the Universe is threaded with well-organized, large-scale magnetic fields. This cosmic magnetism plays a vital role in controlling how stars and galaxies form and evolve. However, the evolution, structure and origin of magnetic fields on the largest scales are still fundamental unsolved problems. I will review a century of studies of cosmic magnetism, beginning with the pioneering experiments of Edison, Lodge and Hale, and concluding with the stunning new views of magnetic fields in interstellar gas, in the Milky Way, and in distant galaxies now being provided by innovative wide-field surveys of radio polarization and Faraday rotation. These experiments pave the way to the opening of the full magnetic Universe with the next generation of radio telescopes, culminating in the Square Kilometre Array.