The only known recordings of a brilliant physicist who predicted the existence of parallel universes have been found in the basement of his rock star son's flat.
The tapes document how Hugh Everett, a quantum physicist, developed his idea at the age of 24, while a graduate student at Princeton University in 1957. Everett's theory gave rise to the concept of a multitude of universes, or a "multiverse", where all life's possibilities play out. It means that somewhere Elvis is still rocking, the Nazis won the second world war and England qualified for Euro 2008.
The recordings are believed to have been made in 1977, after a physics conference at which Everett's parallel worlds theory was resurrected after being shunned for two decades. The tapes were thought lost after his death at the age of 51 in 1982.
They were found during the making of a TV documentary in which Mark Everett, the physicist's son and lead singer of the US band Eels, attempts to understand the work that consumed his father. The programme, Parallel Worlds, Parallel Lives, airs on BBC4 this evening.