 By the time t = t*, the object has literally disappeared from the world—its world-line never reaches the t = t* surface. (Never mind how the object gets accelerated in this way; there are mechanisms that are perfectly consistent with classical mechanics that can do the job. In fact, Xia (1992) showed that such acceleration can be accomplished by gravitational forces from only 5 finite objects, without collisions. No mechanism is shown in these diagrams.) This “escape to infinity,” while disturbing, does not yet look like a violation of determinism. But now recall that classical mechanics is time-symmetric: any model has a time-inverse, which is also a consistent model of the theory. The time-inverse of our escaping body is playfully called a “space invader.”