SPEAKER: Helvi Witek (Nottingham University)
ABSTRACT: Black holes (BHs) are among the most fascinating inhabitants of our universe and, at the same time, our ``eyes'' to explore the limits of standard model physics. In the presence of massive bosonic fields BHs are prone to the superradiant instability, an effect that becomes observationally most relevant for ultralight fields predicted in beyond-standard model physics, such as axions. While this situation by itself has been studied extensively, one may wonder whether in a BH environment these light fields may induce superradiant phenomena when coupled to other (e.g. standard model) fields. To this end we have started to investigate the interaction between axions and electromagnetic fields, stemming for example from accretion disks around BHs, and I will present our first results.