2 ms·
The notion of "backwards" in time is a bit fuzzy once you get into relativity, so the three person example I gave may not clearly show it. However, in the four
by gizmo686 10y ago
The notion of "backwards" in time is a bit fuzzy once you get into relativity, so the three person example I gave may not clearly show it.
However, in the four person example, Dave is able to hand Carol her diary of the trip that she is about to make. If that is not time travel, I do not know what is.
- lisivka 10y agoIt's very unlikely. If Dave has Carol diary, then Carol made the trip already, so Carol will notice empty fuel tanks and big holes in the shield. She will may have problems with memory, but she is not stupid.
- gizmo686 10y agoNo 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.