Wave dark matter (and black holes)

This will be a talk mostly on wave dark matter - if the dark matter constituent is lighter than about 10 eV, dark matter is best thought of as a set of waves. After a brief introduction, we will discuss two recent ideas that explore the implied wave phenomenology: caustic fringes, and ultra-broadband axion dark matter detection. If time permits, we will also discuss some recent work on nonlinear black hole perturbation theory.