Cosmological Magnetic Fields from Ultralight Dark Matter
Speaker
Date
Time
Place
Cosmology Hall (Room 7S1)
Abstract
Assuming that an ultralight pseudo-scalar dark matter field coupled to electromagnetism in the same way as an axion, there is a tachyonic instability which leads to the generation of cosmological magnetic fields right after the time of recombination. I also present a new misalignment mechanism which leads to coherent oscillations of the pseudoscalar field.
Biography
Robert Brandenberger is a theoretical cosmologist and Professor of Physics at McGill University in Canada, known for his pioneering contributions to early universe cosmology and the interface between high-energy physics and cosmology. He is best known for developing string gas cosmology, an alternative to cosmic inflation based on fundamental principles of string theory, and for his influential work on the theory of cosmological perturbations, topological defects, and the trans-Planckian problem in inflationary cosmology.