I think time travel is possible, but you can only change things from the perspective of the person who travelled back. The original timeline just keeps on going.
Person (a) travels back in time to kill Hitler and succeeds. That new timeline exists now without Hitler, but in the original timeline is already written in stone. There is no changing it. The moment that person travels back, they’ve created a new timeline. It’s both impossible for them to change the original timeline, and impossible to ever return to the original timeline because if they go back to the future they’ll only be travelling along the new timeline.
Rhynoplaz@lemmy.world 1 week ago
In Back to the Future, the timelines forked, so as long as they went back before the fork (point in time that a change was made), they would be in their original timeline.
You say there’s no going back to the original timeline, and I’m wondering if and how that would differ from the BttF fork theory.
Adderbox76@lemmy.ca 1 week ago
Because of wave function collapse.
Think of it this way:
We live in a universe where we did NOT travel back in time to kill Hitler.
If we then jump backwards in time to kill Hitler, we create a tangent universe in which we DID travel back in time to kill Hitler.
Its not the act of killing Hitler that creates the tangent universe, its the act of going back in time itself. We are moving from a universe in which we DIDN’T go back in time to one in which we DID.
If we then travel back to before our initial jump backwards, yes, we are travelling back along the original universe, but we are automatically creating a tangent universe starting from THAT point.
Flagstaff@programming.dev 1 week ago
The time-travel visual novel and anime Steins;Gate uses this multiverse premise, yeah.