Three time travelers—Chernikowski, Plant, and the narrator—keep going further and further back in time to escape the wave of destruction that’s seemingly following their time machine.
I do not have to be a physicist, and I certainly am not one, to recall Einstein’s words: “The distinction between past, present, and future is only a stubborn, persistent illusion.”

Variants

(1)
  1. “Zip” by Steven Utley, in Asimov’s Science Fiction, July 2012.
    2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Steven Utley