The MIF concept traces its history to comments by Andrei Sakharov in the 1950s, who noted that a magnetic field in a foil could be compressed and could, in theory, reach millions of Gauss. The concept was not picked up until the 1960s, when Evgeny Velikhov at the Kurchatov Institute began small-scale experiments using metal foils that were imploded by an external magnetic field. It was realized that the cost of the metal liners would likely be higher than the value of the electricity they would produce, the "kopeck problem", and they considered the idea of using a reusable liquid metal liner instead.