Tachyon trajectories in Schwarzschild's space-time

Abstract

The motion of a tachyon in the empty Schwarzschild solution outside a mass m i~ discussea. It is shown that a tachyon falling radially inwards never reaches the space-time singularity at the origin. Instead, it is bounced back at a point inside the Schwarzschild radius. The causal and non-causal aspects of such a bounce are considered. It is shown that a tachyon dropped from a radial co- ol'dinate < 2.56 m always aarives before it went in whereas a tachyon dropped from a radial co-ordinate >3.27 m always arrives later than its starting time. The more general case of a tachyon with a finite angular momentum is also analyzed. The possible astrophysical consequence7 of the presence of tachyons near condensed or collapsing objects and black holes are qualitathely discussed.