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The Observable Universe Might Be A Black Hole, Suggests A Chart Of Everything
(www.iflscience.com)
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this post was submitted on 21 Oct 2023
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note: clickbait sources/headlines aren't liked generally. I've posted crap sources and later deleted or edit to improve after complaints. whoops, sry
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Doesn't that not mesh with the whole "space is constantly expanding" thing?
If the observable universe was all in a black hole, everything would be moving closer together as we get pulled toward the singularity.
...right? Definitely not my area of expertise, but the little I do know is raising a few flags.
Things nearest the center would move towards the center at an accelerated rate. So observation from the perspective of an object falling in the black hole could be everything is expanding? Since everything is getting compressed as it goes toward the center. I’m not an expert on anything but it seems like an intriguing concept.
It won't work like that, the expansion we observe has no directional bias. If it were due to some collapse to a well defined point, we'd be able to tell the difference.
Iflscience is a pop science website. There's no guarantee this isn't bullshit.
You can just read the submission in the AJP issue: https://pubs.aip.org/aapt/ajp/article/91/10/819/2911822/All-objects-and-some-questions
Ifl science was once good, but it's been click baity junk for as long as I can remember now.
This article is pretty pointless, it's not a new observation at all but it doesn't really mean anything. There are a few different reasons we know that the observable universe can't be a black hole.
From the article:
Not saying any of this makes sense, but you seem to be working with different assumptions.
Another narrative could be: As mass gets added to the black hole, it (the universe) grows.
That also isn't how it works, I'm afraid.
The black hole gets less dense because the so called "event horizon" becomes larger, the space inside doesn't stretch like we see in the universe.
It's a little removed from my area, but as I understand it there are similarities in the maths. The observable universe has a horizon in some sense, but it's not a point if no return like a black hole, so much as a point of "the universe hasn't existed long enough for anything to be able to travel that far yet"
This has a similar effect as a black hole, but it's really just a concept we see in perfectly flat empty space, light taking time to move.
There's also an event horizon where space is expanding away from us rapidly enough that we can never get that far no matter how long we travel.
Oh yeah, that's also a great point, the Hubble horizon!
It turns out there are a few different horizons in cosmology like that, they really do show up everywhere.