Warp Drive

Roger Bell_West

May 7, 2013


1 Behaviour

The warp drive has opened interstellar space to humanity. It produces an effect with some characteristics of bias and Alcubierre concepts, but is somewhat more controllable.

The drive generates a force bubble which partly isolates the ship from the surrounding universe, then projects a simulated mass inside it. Within the bubble, space becomes ``sloped'', and the ship will accelerate ``downhill'' towards the simulated mass, gaining velocity; the vehicle is accelerated as a whole, so the occupants feel no force. The bubble may be reinforced, and this is necessary for FTL transitions; its shape is reconfigured, and the ship disappears from normal space.

During FTL flight, no energy can enter or leave the bubble. Speed and direction of flight can be altered, but the ship is entirely isolated from the universe, flying blind. When it returns to normal space, it maintains the velocity it had before the transition. However, even for a transition taking only a fraction of a second, its position is uncertain; it will arrive randomly somewhere within a sphere of roughly 50 AU diameter.

A transition into or out of FTL produces gravity ripples (``wake turbulence''), with strength proportional to the mass of the vessel. These are detectable, and impair (but do not prevent) further FTL transitions within a few hundred thousand miles of the epicentre while they persist (typically for some hours).

Entering normal space interpenetrating an object already there causes an energy release (roughly equal to 10^-7 the interpenetrating mass), in the form of gamma rays. For typical interplanetary and interstellar media this causes only minor radiation damage to ship and crew, but the presence of a solid object (even a dense molecular cloud) is generally fatal.

Therefore FTL travel is a tradeoff: a single long transit will be quicker than several short ones, but will be more risky, as navigational errors are bound to accumulate.

Maximum FTL speed is theoretically infinite; in practice it is dependent on the strength of the field that separates the vehicle from the surrounding universe.

Roger Bell_West 2013-05-07