Conceptual

Wave Dark Matter Scattering Resonances off Supermassive Black Hole Binaries

A first-principles derivation showing that the universal co-rotating density profile of wave (ultralight) dark matter around a supermassive black hole binary is the steady state of a scattering process, with the scattering becoming resonantly efficient when the binary separation matches discrete multiples of the dark matter's de Broglie wavelength (interpreted as bound-state resonances). Estimating the dark matter processed this way at galactic centres, the work predicts an observable change in the slope of the pulsar-timing-array gravitational-wave spectrum, offering a new probe of the nature of dark matter.