Could The Universe Be Inside A Black Hole?

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What is inside a black hole? Inevitable crushing doom? Gateways to other universes? Weird, multidimensional libraries? If you’ve ever wanted to know then you might be in luck - Some physicists have argued that you’re inside one right now.

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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Post Production by Leonardo Scholzer, Yago Ballarini, Pedro Osinski, Adriano Leal & Stephanie Faria
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Directed by Andrew Kornhaber
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[JSorngard]

Oh goodie, some existential dread before I go to bed!

[JasonBoyce]

The idea that our whole universe could exist inside a black hole is pretty amazing. It really reminds me of the meme about how life is formed from all of the elements created from a supernova, and ends with, “If you explode something hard enough, sometimes dust wakes up and thinks about itself”

[gilgamesh.....]

So wouldn't this be a new way to think of multi-universal theory? Because it would mean, at least in theory, that there's potentially a greater/outer universe that spawns black holes that contain nested universes within it. Or it would mean we exist in a fractal reality where instead of turtles it's black holes all the way up and down.

[stacyjohnson]

Black holes and the entire universe and anything and everything about these subjects are actually some of my very very very extreme favorite subjects of all time.

[davewestner]

To me, the most incredible thing about this is that people who study this subject can walk around freely without their brains exploding.
What a confusing subject.

[boukenohryis]

If a black hole is pulling in spacetime, then from the inside, wouldn't it appear to be gaining spacetime, and therefore appear to be expanding?

[mothercrazy]

I like this idea because if true, it also answers the multiverse question. There are lots of black holes and therefore lots of little universes absolutely everywhere. And they could contain their own infinity of black holes. It all makes sense.

[Akadehmix]

I’ve always wondered about this. Mostly because of the theories behind the Big Bang. I always thought that maybe that’s what happens inside a black hole.

[jonathancapps]

So, this video discusses the possibility of our universe being inside a black hole. I've also seen something about our universe possibly being on a 3D event horizon of a black hole in a 4D universe. I don't know if there's enough there for an episode, but it would be cool for Matt to discuss it.

[brucefoote]

Just wanted to say, I'm 70, and started speculating a decade ago the analogies between the collapsing space inside a black hole, and the steadily expanding space-time universe in which we live. I've not known who or how to ask, but I'm so happy to hear it articulated. Now I can die in peace, knowing that speculation is in good hands. Thank You Matt.

[IamKlaus]

Wonderful to see we haven't run out of theories yet.

[bigyeticane]

Wow, what an interesting episode! Thanks everyone who made this!

[chrisjager]

Fun fact, black holes get less dense without limit the bigger they are, because they have a radius r = (2G/c^2) * M directly proportional to their mass. For example, a black hole with the mass of our universe would have a Schwarzschild radius about the size of our universe and a density about the density of our universe.

[jimmygriffiths]

I'm really glad you mention the infinite nesting at the end! It was bugging me the whole time. If the black hole contains black holes, well, then unless the one we are in is unique and the ones inside it are different, it means universes are fractal.

[ethrael]

First time watching. I saw you on Star Talk and figured I'd check it out.
Now I need to add Space Time to my playlist. Great video!

[Kylie-wcgx]

This idea just makes sense to me, I've always had a gut feeling that reality is a fractal. And being inside a black hole makes sense

[theonions]

Thinking about our existence is crazy as it is .. thinking about the universe’s existence is just next level mind blowing craziness

[tudordima]

This is exactly the way I imagine our Multi-verse looks like. The fractal structure of never-ending hard to put in words beatiful infinite reality we're living in.

[PlanetXMysteries-pjnm]

"Your videos always leave me in awe and eager to learn more about the mysteries of the universe. Thank you for fueling my curiosity.
"

[upsyloownmusic]

This has become my favorite space theory of all time, first because it would kinda make sense, and if proved true, it would answer so many questions while also opening the way to a whole new series of thoughts and discussion on what's out there, beyond our bounded universe.