Savannah: We are all allowed to have our own favorite space words, but mine has to be "spaghettification." Okay, it's not a 100% official astronomical term, but it's such a great, if potentially gruesome, visual - why would we need anything else.

But spaghettification describes what might happen to you during your hypothetical descent toward a black hole; you're ripped apart into a noodly stream of subatomic particles. And it's sometimes treated as an inevitability, but because there's still a lot we don't know about black holes, astronomers have proposed ways you could possibly avoid a spaghettified fate.

How does a human body, or any clump of matter, get turned into a noodle? Well, it all comes down to what's called a "gravitational gradient" - how the strength of gravity varies with distance from a massive body. Basically, the closer a bit of matter gets to another bit of matter, the stronger the force of gravity. But it's not a one-to-one relationship. If you cut the distance in half, you multiply the strength of gravity by four.

So imagine you're an astronaut chillaxing near a black hole with your little astronaut booties pointed toward the event horizon - the infamous point of no return where gravity is so strong, you inevitably spiral down into the singularity at the heart of that black hole. Your feet will feel a slightly stronger pull than your head. Far enough away from the event horizon, the difference isn't particularly noteworthy. But as you drift closer and closer, it gets larger and larger; eventually the gravitational gradient is so large, it overpowers the strength of the tissues holding your body together: skin, muscles, bones, and so on. So as you continue your fall, you get ripped into ever smaller pieces, which form a nice, little, noodly line as they all funnel downward.

But how close to the black hole does this spaghettification happen? It all comes down to the black hole's mass, but maybe not in the way you're thinking. For black holes with masses around that of our Sun, you'd become spaghetti before your booties got anywhere near the event horizon. But the more massive the black hole, the larger the event horizon, and the weaker the gravitational gradient.

It seems counterintuitive, but it's a natural consequence of Einstein reconceptualizing gravity itself, and his theory of general relativity. Gravity isn't so much a pull as it is falling along curves in the fabric of spacetime. The more massive a black hole is, the shallower those curves are at its much larger event horizon. So in the regions just beyond that point of no return, gravity's strength changes more slowly. For a bigger black hole, you need to get closer to the event horizon for the full spaghettification effect.

But for supermassive black holes - black holes that are millions, if not billions, of times the mass of a single star - the extreme forces you need to tear your body asunder happen, well, *inside* the event horizon. So if you slip past the event horizon of a supermassive black hole all is not lost. You'll never see your friends or family again, but you might not be spaghettified, because while physicists have plenty of models for what happens inside an event horizon, no one *knows* what will happen. And the math often creates paradoxes.

And trying to solve some of these problems, like not knowing whether or not information is destroyed when it passes through the event horizon, theoretical physicists have proposed some pretty extreme ideas. For example, in 2012, one team suggested that any matter that reaches the event horizon of a black hole would be almost immediately incinerated by a "firewall" of radiation, created as the black hole evaporates. While the idea of a black hole wall of fire is controversial, according to that world view, you *would* escape the fate of spaghettification if you were falling into a supermassive black hole. You're still dead, of course, so it's not a happy ending, but what if there were one?

To avoid death, you would first hope that the black hole you've fallen into is spinning. When pop science talks about spaghettification, or anything to do with black holes really, it's often in the context of non-rotating black holes. But most black holes start off as a dead star; stars rotate at least a little bit, so theoretically, most black holes rotate at least a bit, too.

And because of that rotation, the physics gets pretty complicated. For example, the fact that it spins means it actually drags the fabric of spacetime around it, creating not just one but two event horizons, one inside the other. Most theoretical physicists think that any matter that reaches this inner event horizon before being spaghettified will either finally be torn apart or fried from all the radiation.

But there are a few who think otherwise. Instead, you could experience any one of the infinite number of futures past that inner horizons. Maybe you get the one where you survive your trip through the black hole entirely, because black holes have another weird quirk: the singularity isn't a single point toward which all matter must inevitably tumble - it's a ring. And according to a paper published in 2020, if you came in at just the right angle, you might miss that ring-shaped singularity and end up outside the black hole in another universe - emphasis on the "might."

But you're not in another universe, so back home will have no idea you survived, with no way to observe what happens beyond the black hole's event horizon. We'll never actually *know* if anyone could completely avoid spaghettification, and we'll have to wait for a new theory to unite the physics of the very massive with the physics of the subatomic, before we even have a solid idea of what's really going on down there.

But that means there's hope, right? Maybe that's all we need for now, because we're at least, like, a month away from trying to shoot something into a black hole? We've just got to invent a spaceship that can go faster than the speed of light to get us to the nearest known black hole first. Okay, maybe we're like, *two* months away.

So while humanity waits for scientists and engineers to actually perform some real black hole experiments, we here at SciShow will be over here telling stories about just how awesome and weird they are. We've even got you covered if you're looking for the weirdest of the weird, like this video ["Naked Singularities"] on a hypothetical kind of black hole that isn't even black because it's naked, and this one ["The Kugelblitz"] which asks if we could make a black hole out of light.

So, thanks for watching, and if you'd like to help us cover even more black hole awesomeness, head on over to patreon.com/scishow to find out more.

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