The Dean drive was a device created and promoted by inventor Norman Lorimer Dean (1902–1972) that he claimed to be a reactionless drive.[1] Dean claimed that his device was able to generate a uni-directional force in free space, in violation of Newton's third law of motion from classical physics. His claims generated notoriety because, if true, such a device would have had enormous applications, completely changing human transport, engineering, space travel and more.[2] Dean made several controlled private demonstrations of a number of different devices; however, no working models were ever demonstrated publicly or subjected to independent analysis and Dean never presented any rigorous theoretical basis for their operation. Analysts conclude that the motion seen in Dean's device demonstrations was likely reliant on asymmetrical frictional resistance between the device and the surface on which the device was set ("stick and slip"), resulting in the device moving in one direction when in operation, driven by the vibrations of the apparatus.[3][4][5][6]
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