  Continued gravitational collapse gives rise to curvature singularities. If a
curvature singularity is globally naked then the space-time may be causally
future ill-behaved admitting closed time-like or null curves which extend to
asymptotic distances and generate a Cosmic Time Machine (de Felice (1995)
Lecture Notes in Physics 455, 99). The conjecture that Cosmic Time Machines
give rise to high energy impulsive events is here considered in more details.
