Using only permanent magnets and a light source Japanese scientists have succeeded in controlling the motion of a magnetically levitating graphite disk. The technique can be used to develop light-powered maglev transportation systems and to convert sunlight into kinetic energy.   For their experiment Dr. Masayuki Kobayashi and Professor Jiro Abe of Aoyama Gakuin University in Kanagawa, Japan exploited the diamagnetic properties of pyrolytic graphite. When graphite is exposed to an...