In March 2002, the scientific world was rocked by some astonishing news: a distinguished US government scientist claimed he had made nuclear fusion out of sound waves in his laboratory.
Rusi Taleyarkhan's fusion breakthrough was based on a little-understood process called sonoluminescence. It's a process that magically transforms sound waves into flashes of light, focusing the sound energy into a tiny flickering hot spot inside a bubble. It's been called the star in a jar.
The breakthrough and the paper in Science attracted great scepticism. When fusion takes place, particles called neutrons are given off. These are considered by scientists to be the key signature of nuclear fusion – but measuring neutrons on a small, laboratory scale had proven notoriously difficult in the past – and had even killed off an infamous fusion claim in 1989.