It depends.
this post was submitted on 02 Aug 2025
2 points (54.5% liked)
No Stupid Questions
42629 readers
474 users here now
No such thing. Ask away!
!nostupidquestions is a community dedicated to being helpful and answering each others' questions on various topics.
The rules for posting and commenting, besides the rules defined here for lemmy.world, are as follows:
Rules (interactive)
Rule 1- All posts must be legitimate questions. All post titles must include a question.
All posts must be legitimate questions, and all post titles must include a question. Questions that are joke or trolling questions, memes, song lyrics as title, etc. are not allowed here. See Rule 6 for all exceptions.
Rule 2- Your question subject cannot be illegal or NSFW material.
Your question subject cannot be illegal or NSFW material. You will be warned first, banned second.
Rule 3- Do not seek mental, medical and professional help here.
Do not seek mental, medical and professional help here. Breaking this rule will not get you or your post removed, but it will put you at risk, and possibly in danger.
Rule 4- No self promotion or upvote-farming of any kind.
That's it.
Rule 5- No baiting or sealioning or promoting an agenda.
Questions which, instead of being of an innocuous nature, are specifically intended (based on reports and in the opinion of our crack moderation team) to bait users into ideological wars on charged political topics will be removed and the authors warned - or banned - depending on severity.
Rule 6- Regarding META posts and joke questions.
Provided it is about the community itself, you may post non-question posts using the [META] tag on your post title.
On fridays, you are allowed to post meme and troll questions, on the condition that it's in text format only, and conforms with our other rules. These posts MUST include the [NSQ Friday] tag in their title.
If you post a serious question on friday and are looking only for legitimate answers, then please include the [Serious] tag on your post. Irrelevant replies will then be removed by moderators.
Rule 7- You can't intentionally annoy, mock, or harass other members.
If you intentionally annoy, mock, harass, or discriminate against any individual member, you will be removed.
Likewise, if you are a member, sympathiser or a resemblant of a movement that is known to largely hate, mock, discriminate against, and/or want to take lives of a group of people, and you were provably vocal about your hate, then you will be banned on sight.
Rule 8- All comments should try to stay relevant to their parent content.
Rule 9- Reposts from other platforms are not allowed.
Let everyone have their own content.
Rule 10- Majority of bots aren't allowed to participate here. This includes using AI responses and summaries.
Credits
Our breathtaking icon was bestowed upon us by @Cevilia!
The greatest banner of all time: by @TheOneWithTheHair!
founded 2 years ago
MODERATORS
Assuming it comes back through the portal, and it took 4 seconds with no portal.
Your stopwatch will measure 4 seconds when the portal is there.
A stopwatch in the ball will measure 4 seconds when the portal is there.
If you want to take stepwise measurements based on your clock, the ball will be at time 1 sec before going through the portal, time negative 1,767,225,598 when it hits the wall, 3 sec after it exits the portal second time, 4 sec when it reaches you.
Never. It's in the past?
Why though? In 1969 a ball appeared in the middle of the room, hit a wall and came back towards the portal...
what if the portal didn’t exist in 1969? The ball travels to 1969 and is unable to come back.
Anything coming "back" (which kind of back?) through the portal was not in your scenario specification....
12
42!
Depends on the type of time travel you believe in. My favorite type involves infinitely forking universes, where every event happens and is equally real. You can travel between branches, and each trip also creates another branch every time.
So, let's say you start with universe A, kick the ball into universe B, and it stays there, which results in an "infinite delay". If you're lucky someone in universe C, D, E... etc. kicks their ball to you in universe A. Basically the perceived "time delay" could be anything. Technically, the whole concept of delay is totally invalid, but let's just roll with it.
If they decide to kick the ball to your yesterday, the delay is -24 h. They could also choose to send it at the exact same time your ball went to universe B, so that the event would look just like as if there were no time travel portals. It's up to them really. The delay could be anything they want it to be.
That’s not the time travel I like because it doesn’t create any fun paradoxes!
I support the “unique universe” idea, with all the paradoxes that that can generate. So, you send the ball back to 1969. Has the ball then been bouncing up and down the room since then? You should have seen it when you threw your “new” ball, then!
Or the same ball cannot exist twice at the same time, then somehow the 1969 ball stopped existing when the now-ball got created. And you will never get your ball back because it disappeared in the past.
Or the universe fixes itself, then when your ball disappeared in the time portal, the 1969 version somehow reappeared in the room, but that is the paradox that needs the most “fixing”, so I don’t prefer it
Oh ok, no problem. I can switch to a model that doesn’t shy away from paradoxes and contradictions.
Next, you would need to address what to do with those problems. Can we allow the same thing to exist in two places simultaneously? How about information and items without any origin? Does it matter if the model isn’t consistent or doesn’t make sense? If so, it’s going to be a very flexible tool when writing a scifi story.
Never?