Faster-than-light travel

thumb|upright=1.3|A wormhole visualized as a two-dimensional surface. Route (a) is the shortest path through normal space between points 1 and 2; route (b) is a shorter path through a wormhole.

thumb|330x330px|Because the sphere travels faster than light, the observer sees nothing until it has already passed. Then, two images appear: one of the sphere arriving (on the right) and one of it departing (on the left). Faster-than-light (superluminal or supercausal) travel and communication are the conjectural propagation of matter or information faster than the speed of light in vacuum (). The special theory of relativity implies that only particles with zero rest mass (i.e., photons) may travel at the speed of light, and that nothing may travel faster.

apparent faster-than-light motion of distant astronomical objects

fringe theory claiming to unify quantum mechanics and general relativity

hypothesised phenomenon in quantum field theory

NASA conceptual interstellar ship

2011 experiment which mistakenly seemed to show faster-than-light travel