Kurzbeschreibung (VLB): As 'Faster-Than-Light Particles' G. Feinberg introduced tachyons in 1967. The characteristic quantity for tachyons is their momentum parameter instead of the rest mass of particles. We point out the difference between the terms correlation and interaction. We find tachyons as solutions of the sine-Gordon equation over a lattice structure, what was first done by G. Eilenberger 1981. We investigate collision processes with tachyons and discuss hypothetical consequences concerning particle creation and dark energy. We demonstrate how the Einstein-Podolsky-Rosen paradox can be explained using instantaneous zero-energy tachyons and thus give a model for Zeilinger's teleportation of 1997.