If you had a machine that created a window through which you could see the future, and in the future you wrote down the winning lottery numbers and relayed that information to your present self before that lottery number was drawn.
However, in your present selfs excitement, you turn off the machine before your future self wrote the winning lottery numbers into it for your past self.
What would happen?
I don’t see that as a problem. Every possibility co-exists, and every reality is equally real. Every moment and decision forks the universe in infinite ways, but you get to choose the one where you go.
You can save a drowning person, or let them die, but in the big picture, it won’t matter. That person will drown infinitely many ways anyway, but there are also infinitely many universes where they get saved. Don’t worry about the big picture. What matters, is how you act and how the world acts on you in this universe.
Apologies, I copied and pasted the answer below from another reply I made elsewhere in this thread
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I’m not talking about about the possibility of real infinite dimensions. I’m talking about sci fi, and stories, which is the context of the OPs question.
In a “real” scenario, the experience that matters is the one I’m having, not the one other versions of me might be having.
But in a story, there is no “true” timeline, or a more “real” timeline. They’re all being retold to us indirectly, and the choice of the version of the person retelling those experiences is arbitrary by the author. It doesn’t matter what perspective the author chooses, because every other outcome also happened, the author just didn’t tell us those stories.