Multiverse, not to be confused with Multipass, which is something completely different.
this post was submitted on 22 May 2026
17 points (90.5% liked)
Explain Like I'm Five
21231 readers
8 users here now
Simplifying Complexity, One Answer at a Time!
Rules
- Be respectful and inclusive.
- No harassment, hate speech, or trolling.
- Engage in constructive discussions.
- Share relevant content.
- Follow guidelines and moderators' instructions.
- Use appropriate language and tone.
- Report violations.
- Foster a continuous learning environment.
founded 2 years ago
MODERATORS
Time travel isn't realy possible. No time travel is accurate.
I think Tenet or Primer might be the closest to actually plausable. And they don't realy match what people think of as "Time Travel".
My head canon is the only viable timeline is the one where time travel is never invented.
I’ve not seen either of those but I always imagined if time travel to the past was real, it would be circular, as in, in 2027 I travel to 1950, but right now in 2026 I haven’t travelled yet, but if I were to look, I would have already been in 1950 in the worlds past but my future. Eg Harry Potter, Timeline, etc
Primer is a great flick for thinking the logic through. Unfortunately you'll need to watch it a few times at the very, very least, to get all the interthreading plot lines. But it's fun.
It didn't. It's a movie. They don't care.
There's a conversation between Banner and Rhodes while they're working on the time travel tech that's basically saying "anything we do in the past becomes the new cannon" as a massive handwave. It doesn't make sense at all, the writers know it, so they put that in as a not-so-subtle message to the audience to not take it seriously.
The Loki TV show goes way deeper into the mechanics of MCU time travel. Basically every timeline where they changed the past is supposed to create an alternate timeline that then gets pruned by the TVA, at least until the end of Loki Season 2 where they switch to a full "it's a multiverse, infinite alternate timelines are A-OK" stance.
Still doesn't explain old man Steve Rogers unless he switched timelines to say goodbye to Sam.
The scene where they reference other movies is just establishing the in-universe rules for time travel. Specifically, that when they time travel, they're actually traveling to a different branch of the "many worlds" tree of possibilities. This is a real theory that says that every time a quantum waveform collapses, what's actually happening is that the universe is splitting into multiple copies, one for each possible outcome, so that all the possible outcomes actually happen. So their time travel is actually finding a different universe that is identical to the one they want to travel to. The in-universe consequence of this is that, since they're going to a whole different universe, any changes made there don't affect the universe that they came from.
It's accurate in that the "many words" theory is a real (but unproven, possibly unfalsifiable) theory. It's not accurate in that there's no reason to think you could get from one universe to another. And maybe questionable that a universe identical to your own universe's past actually exists as one of the many words.
It's also internally inaccurate, since Steve Rogers travels to the past and then apparently just waits around to show up in the present again, which is exactly how they said it doesn't work.
There are two "possible" time travel scenarios:
- You go back in time and create a new timeline (Back to the future, ...) so you can't go back to your timeline.
- You go back in time and change the unique timeline (EG) so you memories change and whatever you changed it is now reality.
The difference is if the traveler is linked or not to the traveler's timeline. In the first case, the traveler is not linked and can change anything... But in the traveler's timeline nothing has changed and the travel didn't work.
In the second case, the traveler is linked and anything that changes because of the traveler is now that timeline reality and that can create a paradox. Imagine you go back and kill Trump when he was a kid. But you went back because you know the current Trump, the president. But of you kill him while he is a kid he won't become president and you won't know him so you won't travel back to kill him... so he will grow up and become the president and...
You forgot the third possible "outcome".
In short, you will never change anything in the present, because it already happened.
everything you've wanted to go back and change has already been changed by you, you going back doesn't change anything, because it already happened, you're just tying up and completing the paradox.
There wouldn't be anyone for you to go back and kill because if you did and succeeded they wouldn't even be alive when you decided to go back. E.g. let's say you wanted to kill Hitler (he's already dead) All you've done is one of the failed assasination attempts. And it's only now you realise that was you.
Or you killed Klara Hitler's boy in the cradle whom she would have taught love and kindness to. Lost to recorded history, she adopts a new boy, because evidence of a random (at the time) woman adopting a kid can easily be lost. Now she's got a chip on her shoulder, and she raises her new son with one goal...
Congrats, you are the cause of Hitler.