Alderson drive

The Alderson drive, named after Jet Propulsion Laboratory scientist Dan Alderson, is a fictional device that enables instantaneous interstellar transportation. It is featured in the CoDominium series of Science fiction novels by Jerry Pournelle, including the Mote series by Larry Niven and Jerry Pournelle. Dan Alderson helped Pournelle work out the notional science behind the drive, and how it should work to be a useful plot device.

The Alderson drive is not, strictly, a faster-than-light drive: it can more nearly be likened to a device able to use a form of wormhole, whose entry and exit 'Alderson points' are at either end of an 'Alderson tramline'. Alderson points are difficult to find. Alderson tramlines form between points of equipotential thermonuclear flux located near stars. Not all star pairs form Alderson tramlines, and not all those tramlines which do form are large enough to take a spaceship. This means that in order to travel between star systems, it is frequently necessary to carry out a series of Alderson jumps interspersed with periods of travel between Alderson points in normal space. Alderson tramlines, when they form, form instantaneously, and travel along them appears to take no elapsed time. However, sentient beings who travel using an Alderson drive experience "jump shock", a temporary period of extreme disorientation immediately following an Alderson jump. Computers are affected for an even longer period of time, making it difficult to automate spacecraft after a jump. Spacecraft are thus vulnerable to attack until their occupants recover from jump shock.

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