Some ideas are:
- You branch off into another timeline and your actions make no difference to the previous timeline
- You’ve already taken said actions but just didn’t know about it so nothing changes
- Actions taken can have an effect (so you could suddenly erase yourself if you killed your parents)
- Only “nexus” or fixed events really matter, the timeline will sort itself out for minor changes
- something else entirely
The one where you can only jump forward, not backward. It avoids the common paradoxes.
we already live in that one
See? Problem solved.
I like the one where the motion of the universe is not accounted for, so the travelers drop into empty space. But someone figures out how to use that to travel through space.
Time Wars are fun though. Each prime timeline moving others toward them.
I was just reading this article about a mathematical understanding of closed time-like curves.
In essence, the argument is that time travel to the past is possible with a degree of free will, but you would not be allowed to alter the past in such a way as to remove the motivation for traveling back in time. E.g., it would be like Futurama where Fry kills his grandfather, but he impregnates his grandmother, thus allowing himself to be born. The idea is that the timeline would correct itself and ensure that your future self will always return to the past.
I like the persistent present. We simply live with the paradoxes.
“Remember when Hitler was assassinated in 1919, 1933, 1936, and 1939, then off’d himself in his bunker in '45?”
“An unidentified man in SS uniform reportedly tried to kill Hitler during a rally at the Berlin Sportpalast.” 1939
This was definitely the time traveller.