system
Given the following post, respond as if you're commenting on Reddit:
human
[General] How does time travel work if souls exist?

Let's say my wife dies and her soul plops into heaven. I develop a time travel machine, go back, and save her. Did I just save some carbon copy of her and her soul remains in heaven? Or did I pluck her eternal soul from heaven and place it back where it was before the incident?
gpt
It depends on which time travel system you're using. If it's single timeline, then either you saved her, in which case she never went to heaven, or you didn't, in which case she always did. If it's multiple timelines then souls split each time the universe branches, so there's a copy of the earlier version of her in heaven and another copy in this universe. Or maybe there were infinite copies of the universe to begin with, and in some her soul went to heaven and in others it did not.

Though souls often don't follow the rules of time, so maybe it's different. Perhaps after she dies the first time she reincarnates in the next universe but loses her memories. Perhaps her soul simply exists in all those times and places and also in heaven and the concept of time doesn't matter to a soul.