Fast Radio Bursts from neutron stars plunging into black holes

Fast radio bursts (FRBs) are millisecond-duration intense radio flares occurring at cosmological distances. Many models have been proposed to explain these topical astronomical events, but none has so far been confirmed. Here we show that a novel way involving enhanced giant radio pulses from a rapidly spun-up neutron star near a spinning black hole can explain the main properties of non-repeating FRBs. Independent observations of such pulses, which are not enhanced, from some Galactic pulsars make our model reliable. If correct, our model would imply the existence of event horizons, the Lense-Thirring effect, and a significant spin energy extraction from a black hole. Moreover, an FRB would then probe the pulsar magnetosphere and its emission, and map the strong gravity region near a black hole. Besides, our model predicts simultaneous detections of FRBs and gravitational waves from black hole -- neutron star mergers for fortuitously nearby FRB events.