The Beatles—Paul McCartney, John Lennon, Ringo Starr and George Harrison—on stage during rehearsals at Television House, Kingsway, London, 1963. [D. Redfern / Redferns]
Stephen Fantone, the 2020 president of OSA (now Optica), said decades ago that even coherent laser light starts with a single spontaneous emission event. Similarly, potentially coherent ideas can be spontaneously emitted in a brainstorming event.