Alcubierre Metric
The Alcubierre metric defines the warp drive spacetime. This is a Lorentzian manifold which, if interpreted in the context of general relativity, allows a warp bubble to appear in previously flat spacetime and move off at effectively superluminal speed. Inhabitants of the bubble feel no inertial effects. The object(s) within the bubble are not moving (locally) faster than light. Instead, the space around them shifts so that the object(s) arrives at its destination faster than light would in normal space.
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