Speaker
Description
Axions are a hypothetical class of particle predicted in a variety of settings and of utility in solving many mysteries of theoretical physics, most notably as dark matter candidates and solving the strong CP problem. I will describe recent dramatic progress in understanding what string theory predicts about the properties of axions, and the door this opens to test quantum gravity with cosmological observations, and in the lab. I will thus describe the cosmology of axions, how they differ from other dark matter candidates, and how we might discover evidence for them. Axion stars and axion miniclusters are novel sources of grvitational waves and multimessenger probes of the pre-reionization Universe. Axion haloscopes experiments can be repurposed for high frequency gravitational wave searches. Recently discovered axion quasiparticles can be used not only to detect axion dark matter but also as "analogue" laboratories for exotic physics, such as the gravitational Chern-Simons interaction.
