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Research suggests Big Bang may have taken place inside a black hole

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Re: Research suggests Big Bang may have taken place inside a black hole

#571

Post by mordae »

2OEH8eoCRo0 wrote: post #528
godelski wrote: post #522

Earlier quoted context omitted.

> requires a parent universe Not exactly . A universe can expand, slow down, then collapse. In this case, bouncing back out. Does that repeat forever? Does it lose energy in the bounce? If so, to where and how? > The black hole in the parent universe must be much much bigger than anything we see in ours Yes and no. You're not thinking about contraction. With relativity we can fit a 100ft ladder inside a 10ft barn. Mo…

Where does the information of the previous universe before the bounce go? Is it destroyed?

Maybe we live inside an universal hash function.

Re: Research suggests Big Bang may have taken place inside a black hole

#572

Post by nbulka »

kosh2 wrote: post #515

I have two problems / questions with this: 1. This theory requires a parent universe that can't have been formed inside a black hole. This means there must a be second "universe creation" mechanism that we can / may never know about from our child universe. For me, this doesn't really answer the true question: "How did our universe begin?" Yeah, it may the "unknown field with strange properties" but instead we get an…

We think the universe had to "begin" because we "began" and tend to anthropomorphize. Is that necessarily true? The universe is under no obligation to have a beginning. Sail around the Earth and you might just end up right where you started.

Re: Research suggests Big Bang may have taken place inside a black hole

#573

Post by meta-level »

bglusman wrote: post #278
danieldrehmer wrote: post #96

I sympathize with Lee Smoolin's cosmological natural selection hypothesis, which would require that black holes give birth to new universes within

I can’t beleive you and I are the only ones familiar with, and that no one else referenced or responded to this connection! https://news.ycombinator.com/item?id=44251438

I too read the book and was just searching for anyone mentioning it. Why can such an idea be called new, when someone else already described it decades ago?

Re: Research suggests Big Bang may have taken place inside a black hole

#574

Post by mr_toad »

leiroigh wrote: post #476
jarend wrote: post #350

The article is based on a physics paper (arXiv:2505.23877), not management theory or institutional metaphors. What the paper actually proposes is that the Big Bang may have been a gravitational bounce inside a black hole formed in a higher-dimensional parent universe. Quantum degeneracy pressure stops the collapse before a singularity forms. From the outside, it looks like a black hole. From the inside, it evolves as…

>in a higher-dimensional parent universe That's incorrect: The parent universe is not higher-dimensional, it's the same good old 3+1 as our universe. What they propose is: Let's take our good old GR, and start with a (large, dilute) compactly supported spherically collapsing collapsing cloud of matter. During that, you get an event horizon; afterwards, this looks like a normal black hole outside, and you never see th…

> with the cosmological horizon somehow (?) corresponding to the BH horizon as viewed from the outside.

That’s not mentioned in the summary. After inflation the event horizon would not exist.

Re: Research suggests Big Bang may have taken place inside a black hole

#575

Post by corry »

PaulHoule wrote: post #525
kosh2 wrote: post #515

I have two problems / questions with this: 1. This theory requires a parent universe that can't have been formed inside a black hole. This means there must a be second "universe creation" mechanism that we can / may never know about from our child universe. For me, this doesn't really answer the true question: "How did our universe begin?" Yeah, it may the "unknown field with strange properties" but instead we get an…

I don't see this idea as very new. There are many models of black holes, such as the Schwarzchild solution, that have an area of "asymptotically flat spacetime" which is, from the viewpoint of our universe, part of the black hole. That something happens around the singularity that creates this new universe doesn't sound that crazy. If our universe is a child of another universe and that is a child of another universe…

Do you find the idea of an infinite regress -- "our universe is a child of another universe and that is a child of another universe and so forth" -- holds much explanatory power for you?

To me it's prima facie a hollow explanation. I get that some models, like eternal inflation or certain cyclic cosmologies, entertain the idea of an infinite past or blur the standard arrow of time... but how does pushing the origin question back indefinitely actually resolve anything?

Re: Research suggests Big Bang may have taken place inside a black hole

#576

Post by modderation »

account-5 wrote: post #198
meindnoch wrote: post #101

I've read somewhere an article which posited that our 3D universe might be inside a 4D black hole. When you cross a black hole's event horizon, the radial coordinate becomes timelike, so you lose one degree of spatial freedom. Movement is still possible in the tangential directions however, so what you get is basically an N-1 dimensional universe. So maybe our 3D universe is actually matter that fell into a 4D black…

What's in a 1D black hole?

I'm guessing it'd look something like this on a 1-dimensional number line:

    --- >   | > >> .
The dot in the middle would be the singularity, the pipes the event horizon, and the contents would be increasingly warped spacetime that may or may not exist, depending on your interpretation of things.

Re: Research suggests Big Bang may have taken place inside a black hole

#577

Post by nwienert »

refulgentis wrote: post #553
adwn wrote: post #431

Earlier quoted context omitted.

I can't parse either of your sentences. Maybe you could introduce some intermediate variables, or use parentheses to give them structure?

I can't parse what you're asking for :| Ran my comment + your reply through AI and asked it to respond to you, as I do want to help. Let me know if there's other instructions I can give it, it may have taken your variable ask too literally? :( Here's its output: Sabine Hossenfelder, after distancing herself from academia, has recently pivoted to monetizing a specific narrative: Let’s define Premise A as “String theor…

Pretty valuable to have people who see A to be true, have presumably seen some of B to be true too (trivial to see with the many replication crises) - and then to do their best to disseminate that to the general public so change can be made. I see no problem there, and I'd hate for the case where people were afraid to make content covering it because they were waiting for years for huge studies (which could also be poorly done) to 'prove' it.

Re: Research suggests Big Bang may have taken place inside a black hole

#578

Post by mr_toad »

0x0203 wrote: post #517

If the universe does have a positive curvature as this predicts, would that mean that if we look out into space, we could see the same galaxies multiple times? Or even our own galaxy in the past? Or is the predicted curvature slight enough that anything we might see multiple times is already beyond the limits of visibility due to universe expansion?

Only if the circumference of the universe is small enough for light to have made the round trip since the universe began. But we think that the universe is much larger than that.

https://en.wikipedia.org/wiki/Particle_horizon

Re: Research suggests Big Bang may have taken place inside a black hole

#579

Post by downboots »

joshdavham wrote: post #546
downboots wrote: post #376

Earlier quoted context omitted.

Might I suggest Brouwer's theorem while we figure it out

Could you elaborate? It's been a while since I've done any real analysis/etc.

A 2D version: If you have a map of the place you're in, there must be a point on the map that's in the exact place it represents.

Re: Research suggests Big Bang may have taken place inside a black hole

#580

Post by nwienert »

teaearlgraycold wrote: post #561
tiltowait wrote: post #559

Earlier quoted context omitted.

While I doubt you’re unique in this, I think this is the first time I’ve seen someone say they hope there’s no such thing as free will. Can you explain why you hope everything is deterministic?

Might just be a reflection of my enjoyment of life. I’ve been very lucky on most aspects. Perhaps if things were worse I’d wish for the knowledge that it could have gone differently. But also it would be super trippy and interesting. Knowing just the mass of the universe you’d be able to peer into any time, past or present, and see exactly what happened. But then what happens around areas where people look into the l…

Not much concern for all the people less lucky than you?
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