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
I believe it’s impossible in the real universe.
Sure there are solutions of general relativity that contain time loops, but they require stuff like an infinitely long cylinder, or escaping a spinning black hole, or negative energy. I just don’t believe beings made of finite matter and with finite energy will ever be able to time travel (except into the future at various rates) and that’s the only kind of beings I think exist.
You are currently correct. Things change.
But my question was if it was possible. Not do you believe it’s possible.
You’re right.
It would have to be multiple timelines or single consistent history. Of the two, I think multiple timelines is a little more likely.
The only saving grace of GR based time travel is that we don’t actually know if the weak energy condition is physical. It probably is, but technically it could be a false assumption.
Yeah, but I feel like if it were feasible to violate the condition we would have done it by now (besides the Casimir effect). That’s just an opinion of course, and I’m just an interested layperson, but I know physicists have been trying for at least a few decades.