Next-generation optical interferometry, or the return of Hanbury Brown and Twiss

Hanbury Brown and Twiss are rightly famous as the pioneers of quantum optics in the 1950s, but their real goal was astronomical imaging to the sub-milliarcsecond scale and beyond, enough to resolve stars. This talk will explain how their counter-intuitive technique of intensity interferometry works, and why it has become topical in the 2020s. Four science cases will be briefly discussed: the mass-radius relation in stars, astrometric planet searching, transient fireballs such as novae, and finally, a novel test for LISA.