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No she didn't. X is the point in spacetime where Carol begins her trip. From her perspective, Dave came from the future. The only reason that this cannot happe
by gizmo686 10y ago
No she didn't. X is the point in spacetime where Carol begins her trip. From her perspective, Dave came from the future.
The only reason that this cannot happen is that X and Y are so far away in space, and close in time, that it is impossible to travel between them.
- lisivka 10y agoSorry, I cannot follow you here. Maybe it's well known thought experiment, but I'm unable to find it.