There's no record of any such occurrence ever taking place. Superstitions tell us it can't. That it would mean the end of the universe. A rip in the space time continuum. That it would be too much for reality itself to handle. But it must have happened somewhere, some time. Since travelling back became possible, there must have been instances ... but as I stood there watching me and our eyes suddenly met, it was like a thunderous bolt had hit me for six.