Riemann's Contribution to Flight and Laser Fusion

The Riemannian TraditionThe hydrodynamic method of Bernhard Riemann, particularlyhis 1859 paper on shock waves, has been an essential-andoften secret — ingredient in the development of thermonuclearfusion energy, supersonic flight, and the hydrogen bomb. Thisissue of Fusion looks at Riemann's influence in each of theseareas.• Steven Bardwell and Uwe Parpart discuss the impasse in inertialconfinement fusion research and present a proposal forbreaking this impasse using Riemann's concept of shock waves.• Fusion interviews Adolf Busemann, one of the most outstandingproponents of the Riemannian tradition in this century.A giant in aerodynamics, Busemann has also made majorcontributions to magnetic and inertial fusion.• Charles B. Stevens reviews the Progressive case, the government'sattempt to block publication of an article on theH-bomb. As he shows, what the government wanted to classifywas not the bomb, but Riemann's theoretical work.Above: Participants at the 1935 European aerodynamics conference atVolta, Italy, a milestone in the development of supersonic flight. AdolfBusemann is fourth from left, third row. Theodor von Karman (white coat) isat his left in the second row; Ludwig Prandtl is fifth from left, first row.Below left: Computer simulation of two shock waves propagating through apellet containing deuterium-tritium fusion fuel. See page 29.Below right: The November 1979 Progressive article. As Fusion hasdocumented, the so-called secrets that the government wanted to classifyhave been in the open literature since 1859.The cover: The front cover photograph, showing shock wave formation around a testmodel of the space shuttle in a wind tunnel, is courtesy of Ames Research Center.NASA: cover design is by Virginia Baier.