I could read Finn's the anger and frustration, well done.

Also was fun to read about gravitational waves, which I just happen to know what they are. Heh.

And ya, the ending was a nice touch. But I wonder if they're now stuck in a loop forever. Because rewinding the simulation might not diverge results. Finn might not remember what happened in the previous iteration.

Well, obviously Finn does recall the previous iteration, otherwise he would never be able to break from the loop of the first time he tested it.