APEC Seminar (Astronomy - Particle Physics - Experimental Physics - Cosmology)

Speaker: Mark Hertzberg (TUFTS)
Title: Nonlinear Behaviour of Axions
Date (JST): Wed, Dec 16, 2020, 10:00 - 11:00
Place: Zoom
Related File: 2619.pdf
Abstract: In this talk I begin by reviewing how dark matter axions may form condensates, and the relation to classical field theory. I review how such condensates are spatially localized clumps, as they are organized by gravitation and self-interactions, discussing both the ground state and finite angular momentum states, which may populate the galaxy. I then discuss the exotic possibility of parametric resonance of these axion clumps into electromagnetic waves, after mergers, which may leave an astrophysical signature. I also discuss using ultra-light axions to resolve the core-cusp problem at the center of galaxies. Finally, I discuss the rate of decoherence of dark matter axions that are in non-trivial quantum states.