cover image Rising Force: The Magic of Magnetic Levitation

Rising Force: The Magic of Magnetic Levitation

James D. Livingston. Harvard Univ., $27.95 (260p) ISBN 978-0-674-05535-3

In this follow-up to his earlier book on magnets, former GE physicist and MIT lecturer Livingston (Driving Force) explains the science and mysteries of magnetic levitation, or "maglev." The ability of like poles of magnets to repel each other has led to the development of popular toys, such as the Levitron, and widely publicized stunts, such as levitating a frog ("diamagnetic") or a person (mildly magnetic). Magnev turns out to have more important applications%E2%80%94from wind turbines on the roof of actor Ed Begley Jr.'s house, to new techniques for minimally invasive surgery, to heart pump replacements. Although eddy currents and superconductors are important for modern-day feats of levitation, it was feedback systems that enabled engineers to apply maglev to larger bodies, such as trains. Livingston explains why the proposed Orlando maglev train system failed, and why the most successful maglev train is an expensive airport shuttle in Shanghai. Some scientists hope that NASA will keep trying to incorporate maglev into rocket launches. General science and technology buffs will find this accessible book fascinating and might be tempted to try a little levitation themselves. (May)