Speaker 1: Sometimes science comes up with the worst name for things
Speaker 1: they discover. I know, like killer whales, which aren't killer
Speaker 1: and are not actually whales, they're actually dolphins. Excellent point.
Speaker 1: But I was actually thinking about black holes. Okay, that's
Speaker 1: one of my favorite space names. What's round with black holes?
Speaker 1: It's an awesome name. But black holes aren't totally black
Speaker 1: and they're not actually holes. Their dolphins, all right? Who
Speaker 1: runs the science pr department here? I think it's run
Speaker 1: by a bunch of dolphins, a bunch of killer dolphins.
Speaker 1: So long and thanks for all the fish. We're heading
Speaker 1: to the black hole. Hi. I'm Jorge and I'm Daniel,
Speaker 1: and this is Daniel and Jorge. It's explain the Universe today.
Speaker 1: We're going to ask the question what is inside a
Speaker 1: black hole? Maybe the deepest, darkest mystery in the universe.
Speaker 1: But first, as usual, we went around and asked people
Speaker 1: on the street what do they know about black holes
Speaker 1: and what's hiding inside them. Here's what they had to say.
Speaker 1: A bunch of destroy destroyed matter and energy. I don't
Speaker 1: know exactly what's inside, but like it like captures light,
Speaker 1: and it has a gravity so like strong that like
Speaker 1: after a certain point you can't escape it Isn't it
Speaker 1: like a vacuum? The anti universe, I don't know. Holy moly,
Speaker 1: I love some of those answers the anti universe. It
Speaker 1: seems like most people kind of had had had a
Speaker 1: good idea of what a black hole was, right, Like
Speaker 1: a lot of people knew it was like a dance mass, right, Yeah,
Speaker 1: it's like a gravitational trap things can't escape from. People
Speaker 1: seem to have the basics out there, right that they're ends,
Speaker 1: they're dark, and things can't escape from them. Right, But
Speaker 1: nobody named knew what's inside of one. That's right. Nobody
Speaker 1: could tell us what was inside a black hole. Apparently
Speaker 1: just walking around in the street isn't the best way
Speaker 1: to get a solid scientific answer. But anyway, it's a
Speaker 1: black hole. So I guess you know, before we talked
Speaker 1: about what's inside a black hole, we should still recap
Speaker 1: what is a black hole? Yeah? What is a black hole?
Speaker 1: Black Holes are sort of fascinating ideas because for a
Speaker 1: long time people thought black holes were just sort of
Speaker 1: like a mathematical curiosity, like the kind of thing that
Speaker 1: you see in an equation. Then if you believe that
Speaker 1: equation describes reality, then it suggests black holes might exist.
Speaker 1: But it's the kind of thing that makes you wonder,
Speaker 1: is this really true or it's just so sort of
Speaker 1: like a weird feature of the equation, something people are
Speaker 1: not going to actually discover. What do you mean, like
Speaker 1: this is the origin of the idea of black holes,
Speaker 1: Like it was actually a theory first wasn't observed or
Speaker 1: anything exactly. The idea of black holes came from general relativity,
Speaker 1: and it wasn't observed for decades later. In fact, Albert
Speaker 1: Einstein thought black holes would never or be seen. He
Speaker 1: thought they didn't really exist, even though his theory predicted them.
Speaker 1: What did the theory predict. Einstein's basic idea is that
Speaker 1: gravity is not a force like other forces things that
Speaker 1: pull and push on each other, like electromagnetism and the
Speaker 1: weak force. He thought gravity instead was just a bending
Speaker 1: of space time that his idea was any mass which
Speaker 1: is sort of bend space. So imagine like a rubber
Speaker 1: sheet spaces that rubber sheet, you put something big and
Speaker 1: heavy on it, it bends things down. Now, if you
Speaker 1: want to marble, you roll marble across that sheet instead
Speaker 1: of just going flat across the sheet. If it encounters
Speaker 1: someplace where the sheet is bent, it's going to change
Speaker 1: its path. So the marble thinks it's going straight. But actually,
Speaker 1: like the rubber it's it's on is curved. That's right.
Speaker 1: It's that the most direct path is now curved with
Speaker 1: respect to your previous path. And that's a tricky concept
Speaker 1: for people to understand that. It's the bending of space,
Speaker 1: and it's the sort of intrinsic bending. It changes the
Speaker 1: natural straight lines. Um. But I love how you say
Speaker 1: the marble thinks it's going straight, Like you have this
Speaker 1: tendency to anthromorphize everything, like we were talking about that
Speaker 1: last time. In this case, like the marble has an
Speaker 1: opinion like, hey man, I'm going straight. I don't care
Speaker 1: what space says. Cartoon is I imagine that you look
Speaker 1: at the world and see little cartoon thought bubbles on everything.
Speaker 1: That's my world. So we were talking about very heavy objects.
Speaker 1: So the idea is very heavy masses bend space. Right,
Speaker 1: the bend space so that when you move through space,
Speaker 1: you end up moving through a curved path. Right, and
Speaker 1: Einstein and some then some later folks realized that there
Speaker 1: are some solutions to the general relativity equations where space
Speaker 1: has bent so much that you can imagine it's like
Speaker 1: a bottomless hole in that rubber sheet, so the things
Speaker 1: can never escape them. And Einstein and these other folks
Speaker 1: they discover these features the equations, but they were like,
Speaker 1: is this real? You know? And this goes to the
Speaker 1: heart of some of the stuff I love, like the
Speaker 1: connection between physics and math, right, we like we use
Speaker 1: math as a language of physics to describe the universe,
Speaker 1: and sometimes the math takes this in directions where we're like, no,
Speaker 1: that doesn't really work here. The math is not physical, right, Well,
Speaker 1: like throw away mathematical ideas that we say are not
Speaker 1: physical because they don't describe what actually happens. Sometimes the
Speaker 1: math describes something which we think is unphysical it turns
Speaker 1: out to be real and that's that's what happened here,
Speaker 1: which is pretty cool. Well. Um, so the math predicted
Speaker 1: that if you you might have a situation where we
Speaker 1: have so much mass in such a small space that
Speaker 1: will distort space so much that it will sort of
Speaker 1: create almost like a hole in space. Yeah, like a
Speaker 1: bottomless hole in this rubber sheet, so that even light
Speaker 1: which travels you know, the fastest thing in the universe. Um,
Speaker 1: can't escape because the all the straight line paths are closed. Now. Wow,
Speaker 1: So like you're so dabbed down into the whole of
Speaker 1: the barberschee, you'd have to be pointing up basically to
Speaker 1: get out. There's no path out. Yeah, exactly. Um, you
Speaker 1: know those big funnels they have in lots of science museums.
Speaker 1: You can put a penny in and it rolls around.
Speaker 1: It goes faster and faster and faster than it drops
Speaker 1: down to the hole. You can think of it sort
Speaker 1: of like that, but imagine that when you're down in
Speaker 1: the hole, right, there's no way for the penny to
Speaker 1: roll up and out of that hole. Right, Okay, So
Speaker 1: so that so it started off as a mathematical weird case,
Speaker 1: right for Einstein, and he was a smart guy, but
Speaker 1: he didn't think that that could actually exist in real life. Yeah,
Speaker 1: he thought it wouldn't actually happen because he thought that
Speaker 1: everything spins and because things spin, it it's harder for
Speaker 1: them to collapse. Right. You can think of most of
Speaker 1: the stuff in the universe as sort of a battle
Speaker 1: between gravity and some sort of pressure keeping it from collapsing.
Speaker 1: Like gravity wants to suck stuff together, rightsh them together. Yeah,
Speaker 1: it's weak, but you give it enough time, it's going
Speaker 1: to pull things together and make them tighter and denser
Speaker 1: and denser. So you might ask, well, why isn't everything
Speaker 1: in the universe a black hole? Like it's fourteen billion
Speaker 1: years in the gravity has had a lot of time.
Speaker 1: You know, why is the Sun not a black hole?
Speaker 1: Or why is the Earth not a black cool? Because
Speaker 1: gravity has compressed them. Um. And the answer in many
Speaker 1: cases is that they're spinning, and the spinning provides a
Speaker 1: sort of a rotational pressure. Think about what happens when
Speaker 1: you're standing on a merry go round, right, Um, somebody
Speaker 1: spins it, you can get thrown off the merry go round.
Speaker 1: And so that's sort of rotational pressure that keeps you
Speaker 1: from getting sucked in. And our galaxy and the Sun
Speaker 1: and the Earth, all these things are spinning, and it
Speaker 1: does make it harder to become a black hole. And
Speaker 1: so Einstein thought that there's no way you could ever
Speaker 1: see this because things were spinning, and that we wouldn't
Speaker 1: ever actually see a black hole would be impossible for
Speaker 1: them to create. He thought gravity could never actually crunch
Speaker 1: anything down that's small, because at that size things would
Speaker 1: sort of spin outwards more than gravity could crunch them in.
Speaker 1: But then he was proven wrong, Like, we actually saw
Speaker 1: black holes. That's right, and I want to talk a
Speaker 1: little bit more about that, but first a quick break. Yeah, so, um,
Speaker 1: we should talk about how you can see a black hole. Right.
Speaker 1: I imagine you see like a little black dot or
Speaker 1: a black circle in the sky or something. So a
Speaker 1: black hole is so heavy that light can't escape it,
Speaker 1: and that means that it doesn't reflect any light. Right,
Speaker 1: you shot a flashlight on it, no light comes back. Right,
Speaker 1: you shot a spotlight on it, shot a laser on it,
Speaker 1: shown anything on it, No light comes back. Even if
Speaker 1: there has the sun next to it, who won't bounce off.
Speaker 1: That's right. No light reflects, and it also doesn't admit
Speaker 1: any light. Now, there's a tiny asterisk we should talk
Speaker 1: about later, which is called hawking radiation. Turns out, black
Speaker 1: holes do give off a little bit of energy, but
Speaker 1: you can't really see it. So from the point of
Speaker 1: view was seeing a black hole, it's basically invisible. It's
Speaker 1: just like a black circle, right, So how could you
Speaker 1: possibly see that a black hole is there? Well, you know,
Speaker 1: I watched the movie Interstellar, which I know could be
Speaker 1: a whole topic of conversation, but that your research for
Speaker 1: the podcast. That and I read the Wikipedia page for
Speaker 1: the black Hole movie, which is a classic seventies movie.
Speaker 1: Did you ever watch the movie? Yes? It did. In fact,
Speaker 1: I saw that movie a few weeks ago with my kids.
Speaker 1: No way, really. I think it was supposed to be
Speaker 1: like a response to Star Wars or something, um and
Speaker 1: it's much weirder than Star Wars. According to Wikipedia, it's
Speaker 1: like the first Disney movie ever to get a PG rating.
Speaker 1: My kids were like, why did you show us this movie?
Speaker 1: Was this supposed to be good? Or is this educational?
Speaker 1: But this that movie was a huge part of my childhood,
Speaker 1: you know. It was like made a huge impression on me.
Speaker 1: You saw the black Hole movie as a kid? Yeah,
Speaker 1: you didn't see this again? You might have been the
Speaker 1: only one. I don't think it was very It was
Speaker 1: huge in Panama. What are you talking about? Huge in Panama?
Speaker 1: I rest my kids. Yeah, let's hope this podcast is
Speaker 1: huge in Panama. Let's hope we we achieved that level
Speaker 1: my fellow Panamanians. I hope they're listening. So how could
Speaker 1: you actually see a black hole? Let's shift out of
Speaker 1: the fictional world and back into the what we imagined
Speaker 1: to be the real world. How could you see a
Speaker 1: black hole? Well, it's biggest to funding feature is it's gravity,
Speaker 1: and so it has very powerful gravity, and you can
Speaker 1: see the effect of gravity on nearby stuff. So, for example,
Speaker 1: one of the biggest black holes that's near us is
Speaker 1: at the very center of the Milky Way. There's an
Speaker 1: enormous black hole there. It's huge. It's called super massive
Speaker 1: and um that's the category of black hole. And we
Speaker 1: can see that it's there because we see stars orbiting it.
Speaker 1: So we see the path of stars that are going
Speaker 1: around the black hole, so we can tell these stars
Speaker 1: are orbiting something, but we see nothing there. So you
Speaker 1: can do the calculations. You can say, oh, all these
Speaker 1: stars orbits are consistent with something really heavy here. Like
Speaker 1: imagine you were looking at the Solar System and you
Speaker 1: couldn't see the Sun. You could guess that there was
Speaker 1: something really massive there because see, look all these planets
Speaker 1: they are going around and they're all consistent with orbiting
Speaker 1: one thing that's really heavy, and you can even calculate
Speaker 1: its mass from the orbits and all that stuff. You
Speaker 1: could deduce that the Sun was here without actually seeing it.
Speaker 1: That would be a pretty silly way to see the sun.
Speaker 1: But you could definitely tell. And we can use that
Speaker 1: same approach, and we have to see the huge black
Speaker 1: hole in the center of the Milky Way for example.
Speaker 1: I see. Maybe that's the problem is that the closest
Speaker 1: black holes to us is at the center of the
Speaker 1: Milky Way galaxy. Now that's the closest, really big one.
Speaker 1: It's like twenty seven thousand light years. I think that's
Speaker 1: pretty far away. There are closer black holes to us
Speaker 1: than the one at the center of the Milky Way,
Speaker 1: but they're not as large, I see. But there's a
Speaker 1: theory about what they sort of look like, which is
Speaker 1: like a black ball, right, yeah, and there's other stuff
Speaker 1: near the black hole, right Like say, for example, you
Speaker 1: have a black hole and it's near a star. What's
Speaker 1: it gonna do. It's gonna shred the star. It's gonna
Speaker 1: suck all the stuff out of the star into the
Speaker 1: black hole. And you can see that also before stuff
Speaker 1: falls into the black hole, you can see it like
Speaker 1: on the way you know. Um, So for example, imagine
Speaker 1: there's like a you know, a hole in the sidewalk
Speaker 1: and everybody's falling into it. If you notice that trail
Speaker 1: of people walking along the sidewalk and then nothing on
Speaker 1: the other side, Oh my gosh. Exactly. So there's lots
Speaker 1: of black holes where you can see the stuff falling
Speaker 1: into it because it and sometimes it's like orbit once
Speaker 1: or twice before it falls in. This this thing called
Speaker 1: the accretion disk, which is like the stuff orbiting the
Speaker 1: black hole before it comes in. And so a lot
Speaker 1: of times you can see that around the black hole. Um,
Speaker 1: it's sort of like a warning, like, you know, abandoned,
Speaker 1: hope all you who fly near here because you are
Speaker 1: entering the black hole. But that also brings up another
Speaker 1: really interesting point, which is like a black hole is
Speaker 1: not a hole. You know, it's a clever name and
Speaker 1: it sounds awesome, and it's connects to this sort of
Speaker 1: geometric idea of like having a hole in the bottom
Speaker 1: of the rubber sheet. But I think most people think
Speaker 1: of a black hole is like a hole in space,
Speaker 1: like something you could fall into, right, But as you
Speaker 1: said earlier, a black hole is something that's really dense,
Speaker 1: it's really heavy, it's really thick. You can't fall into it.
Speaker 1: It's more like a black Man as sort of like
Speaker 1: a black rock. You know, it's like saying, can you
Speaker 1: fall into the earth? Right, Like, you can't fall into
Speaker 1: the earth, you fall onto the earth. Right. Well, you're
Speaker 1: sort of assuming you know what's inside a black hole? Right? Well,
Speaker 1: we know it's really dance, right, we know there's a
Speaker 1: lot of stuff in there. But in terms of like space,
Speaker 1: like space is so distorted. It's sort of like a hole,
Speaker 1: isn't it. It's like the rubber sheet analogy. It is
Speaker 1: sort of a like a three D hole. It's like
Speaker 1: it's through a hole in three D space. Right, it's
Speaker 1: a gravitational well that you can't climb out of. But
Speaker 1: that doesn't mean that it's like empty inside. You can
Speaker 1: like once you go in, you can like dance all
Speaker 1: around is playing the room. Let's think about that this
Speaker 1: sort of where is the edge of the black hole?
Speaker 1: And a lot of people think of the edge of
Speaker 1: the black hole as something we call the event horizon. Okay,
Speaker 1: what's the event horizon? Besides being a bad science fiction
Speaker 1: movie with Sam Neil, the Event Horizon is another movie.
Speaker 1: I see you're not up on your bad sighest fiction cinema.
Speaker 1: Did this? Did this? Only come out in Panama. No,
Speaker 1: this was a real movie. It had like fishburn I
Speaker 1: think Sam Neil. It was like a big deal. But anyway, so,
Speaker 1: what is the event horizon of a black hole? Yeah,
Speaker 1: so that's the point after which you can't escape, right,
Speaker 1: if you are closer to the center of the black
Speaker 1: hole than the than this threashold you can't escape. Outside
Speaker 1: of that, there's still a possibility. Inside there are no paths.
Speaker 1: It's like, you could escape if you could move faster
Speaker 1: than light. But even if you were like moving at
Speaker 1: the speed of light, you could not escape. But be
Speaker 1: careful because people like to say, oh, maybe if you
Speaker 1: went faster than the speed of light, blah blah blah.
Speaker 1: But going faster than the speed of light, that's a
Speaker 1: whole other podcast we should do. Right, it's impossible, And
Speaker 1: so saying something like going fast in the speed of
Speaker 1: light is like saying like, well, then if you had magic,
Speaker 1: then sure all the rules would be off. So like
Speaker 1: an interstellar when they shared the black hole, is this
Speaker 1: black sphere, that's the event horizon, right, that's like the
Speaker 1: edge of that sphere black circle is the event horizon
Speaker 1: because anything inside would just look black. So Is this
Speaker 1: a PHY six podcast asked or a film podcast? Film
Speaker 1: six podcast? No? But I mean, I guess you know what.
Speaker 1: The reason I bring it up is that, you know,
Speaker 1: I think a lot of people have heard of the
Speaker 1: event of horizon, right, and the conceptually what it is
Speaker 1: you can't escape after that, but like a representation of
Speaker 1: a black hole, that that circle is kind of the
Speaker 1: event horizon, right, Yeah, you're exactly right. And so you
Speaker 1: would see like the accretion disk around the black hole,
Speaker 1: the stuff that's about to fall in, like what's on
Speaker 1: deck to get sucked up by the black hole. But
Speaker 1: you're right, the black hole itself would be black, and
Speaker 1: that's the event horizon. You're seeing the edge because you
Speaker 1: can't see anything in it, nothing can escape it, and
Speaker 1: so it's surrounded by matter which you can normally see.
Speaker 1: But the actual black hole itself is the edge of
Speaker 1: the event horizon, and that's what that's what makes the
Speaker 1: questions how interesting. Because you can't see in there, people
Speaker 1: wonder what's in there? Right. Einstein's original idea was that
Speaker 1: there was something called a singularity that's a point of
Speaker 1: essentially infinite density at the very center of it. Right,
Speaker 1: that's right, Yeah, an infinite least small space, right, super
Speaker 1: super dense. As soon as you cross some threshold of
Speaker 1: mass density, then you've created this hole in the bottom
Speaker 1: of the rubber sheet, a gravitational well that nothing can escape.
Speaker 1: But it's not necessary that the whole event horizon is
Speaker 1: filled in with mass. I think this is the point
Speaker 1: you were trying to make earlier. There's got to be
Speaker 1: a dense core in there somehow, but it creates a
Speaker 1: gravitational well that's larger than that core um. And so
Speaker 1: this is the original idea in stands. Original idea was
Speaker 1: that there's this singularity, this really really dense point. Okay,
Speaker 1: so maybe a black hole is like some kind of
Speaker 1: point surrounded by who knows, but it sort of goes
Speaker 1: out to the sphere of blackness. That's going to be
Speaker 1: the name of our band, right, Sphere of Blackness or
Speaker 1: my next Panamanian bad sci fi movie. I think that's
Speaker 1: a la. There's so many concepts tied together into a
Speaker 1: black holes. But I think people still wonder what's inside
Speaker 1: a black hole because we're pretty sure that this idea
Speaker 1: of a singularity can't be right, pretty sure that there
Speaker 1: aren't singularities inside black So not even our theory about
Speaker 1: what's inside is right, yeah, And you know, Einstein's theory
Speaker 1: is wonderful and it's beautiful, and it's predicted lots of
Speaker 1: stuff which seemed weird but actually happens, like gravitational waves. Right.
Speaker 1: Einstein predicted gravitational waves, these ripples in space time when
Speaker 1: massive objects slam into each other or spin around each
Speaker 1: other a hundred years before we saw them, right or
Speaker 1: hurt them as yeah, yeah, decades and decades, I don't
Speaker 1: remember the exact date, but a long time before we
Speaker 1: saw them. And the problem with Einstein's theory is that
Speaker 1: it doesn't include any quantum mechanics. And that's because we
Speaker 1: figured out quantum mechanics sort of at the same time
Speaker 1: or in the decades after general relativity. And something really
Speaker 1: important about quantum mechanics is that it doesn't allow things
Speaker 1: to be located in infinitely small spaces. There's a basic
Speaker 1: fuzziness to the universe and you just can't violate that.
Speaker 1: So having a singular already like a point of matter
Speaker 1: in its zero volume is you know, it would blow
Speaker 1: a quantum mechanics mind, right, but it's it's I guess
Speaker 1: technically quantum mechanics is about momentum, right, Momentum has a
Speaker 1: minimum size. Right, Well, it is about momentum, but it's
Speaker 1: about actually most measurable things like time, energy, space, and momentum.
Speaker 1: All these things come in finite grains like little quantum,
Speaker 1: a little basic units that you can't get smaller than.
Speaker 1: But even if, what if, like it's infinite mass, like
Speaker 1: a black hole, or like infinite density. Yeah, well, the
Speaker 1: quantum mechanics tells us that doesn't exist. You know that
Speaker 1: there's a there's a finite width to everything, and so
Speaker 1: you can't have infinitely small objects um. Quantum mechanics says,
Speaker 1: it just can't happen. But something is happening in there, right,
Speaker 1: there's something going on inside a black hole, and whatever
Speaker 1: it is, it's intense enough and dense enough to create
Speaker 1: a black hole. You don't need infinitely small points to
Speaker 1: create a black hole. You just need a density above
Speaker 1: a certain thresh hold. Genel relativity tells us it's an
Speaker 1: infinite singularity, but coonum mechanics says it can't be infinite. Right. Yeah,
Speaker 1: there's this idea that I thought was really cool that
Speaker 1: anything can become a black hole. Like if you squeeze
Speaker 1: it enough, it becomes a black hole. Right, Like if
Speaker 1: somebody squeezed me and my mass into a small enough volume,
Speaker 1: I would just like become a black hole, right. Yeah,
Speaker 1: it's a great idea, And I'm not sure like technically
Speaker 1: anything can become a black hole because you need to
Speaker 1: have a certain amount of mass per volume. But I
Speaker 1: guess in principle, if you compress something down far enough
Speaker 1: and it had some mass, then it would be dense
Speaker 1: enough to become a black hole. And black holes don't
Speaker 1: have to be huge. Black holes can also be tiny.
Speaker 1: For example, we're trying to create black holes at the
Speaker 1: large age on collider and those would be black holes
Speaker 1: like the size of protons. That is a great thought
Speaker 1: that I don't think a lot of people know is
Speaker 1: that black holes can be different sizes. Yeah. Absolutely, you
Speaker 1: can have a tiny one, or a huge one or
Speaker 1: an super massive gigantic one. That's right. And basically the
Speaker 1: only thing you can know about a black hole from
Speaker 1: the outside is um it's mass, which means its size,
Speaker 1: and it's rotation, so it's whether it's spinning or not.
Speaker 1: And so that's why we desperately want to know what's
Speaker 1: inside a black hole beyond our just our curiosity. Like
Speaker 1: anytime there's something in the universe you can't it's something
Speaker 1: in your house, for example, that you aren't allowed to
Speaker 1: look inside. Like if I said or I never look
Speaker 1: inside this box, you'd be definitely curious to see inside it. Right,
Speaker 1: So you're saying it's like the universe has has created
Speaker 1: a box and it it refuses to tell us what's inside.
Speaker 1: That's right, Well, this is a perfect point to take
Speaker 1: a break. If you could see inside it, um, you
Speaker 1: would learn something really deep about the way gravity works
Speaker 1: and quantum mechanics and how they're connected. It's like, you know,
Speaker 1: ten Nobel prizes worth of stuff hiding inside a black hole,
Speaker 1: maybe even an actual Nobel prize. So that's the answer
Speaker 1: to the question what's inside a black hole? Is uh,
Speaker 1: fame and fortune, a trip to Stockholm. So what would
Speaker 1: happen if you try to get near a black hole? Well,
Speaker 1: this is something you have to understand, which is something
Speaker 1: called a tidal force and um best way to understand
Speaker 1: it maybe is to think about what happens when things
Speaker 1: get near the sun for example. So one of my
Speaker 1: favorite examples came in when this comet came into our
Speaker 1: solar system and approach really close to the Sun. It's
Speaker 1: called comet Shoemaker Levy. That is that the one that
Speaker 1: almost missed Jupiter, That's the one that slammed right into Yeah. Yeah,
Speaker 1: it was pretty awesome to watch cosmic collisions. Um, but
Speaker 1: before it got there, it got torn apart by tidal forces.
Speaker 1: Oh shredded. Yeah, I got shredded. And um, say you're
Speaker 1: near a black hole, or you're near the Sun or something,
Speaker 1: then your head and your feet are not the same
Speaker 1: distance from the Sun. And because gravity depends on the distance,
Speaker 1: so like your head will be pulled in with greater
Speaker 1: force than your feet. If your head or closer than
Speaker 1: your feet, then yeah, there'll be a stronger force on
Speaker 1: your head than there is on your feet, right and
Speaker 1: effectively that means it's tearing you apart. But the difference
Speaker 1: would have to be greater than the forces holding me together. Exactly.
Speaker 1: Like right now you are sitting on the earth, and
Speaker 1: there is a greater force on the on your feet
Speaker 1: then there's on your head. So whatever part of your
Speaker 1: body is on the floor right now is feeling a
Speaker 1: stronger gravitational force than whatever part is elevated, right, Because
Speaker 1: it's further from the center of the Earth, gravity falls
Speaker 1: like one of the distance squared. So that's that's a
Speaker 1: pretty big factor. But the difference is not enough to
Speaker 1: overcome the forces that are holding me together. That's right,
Speaker 1: you're saying near a black hole, those differences are so
Speaker 1: huge he would actually shred your part. Yeah, exactly, like
Speaker 1: that comment that came into the Solar System got shredded
Speaker 1: by Jupiter and by the Sun. If you got too
Speaker 1: close to a black hole, you would get torn apart
Speaker 1: before you got anywhere near it. So it's in my
Speaker 1: view it's impossible to get very close to a black
Speaker 1: hole unless you're incredibly strong, like you need to build
Speaker 1: an object with really really tight bonds. Right. The things
Speaker 1: that are holding me together are the electromagnetic bonds between
Speaker 1: the atoms in my body, and gravity is constantly tugging
Speaker 1: on those if I'm near the Earth or near the Sun,
Speaker 1: tugging on those. But you know, not so hard and
Speaker 1: and where we've evolved to be strong enough to to
Speaker 1: not be shredded by the Earth, but not it's strong
Speaker 1: enough to be to not be shredded by a black hole. Right,
Speaker 1: So basically we may never be able to like go
Speaker 1: to a black hole and see what's inside, right, it's
Speaker 1: hard to imagine and and I hate to say never.
Speaker 1: I disamber because it prescribes future generations intelligence and there's
Speaker 1: probably some genius out there was a clever idea for
Speaker 1: how to do it. It's not theoretically impossible to be
Speaker 1: near a black hole. It's just practically very difficult, which
Speaker 1: makes it, you know, a pretty tough engineering problem. So
Speaker 1: we know black holes are out there, we know they're mysterious,
Speaker 1: we know they contain some deep, dark secret. We don't
Speaker 1: think they contain the anti universe. I don't believe they
Speaker 1: contain worm whole. I don't know, you know, they don't
Speaker 1: believe they contain worms or anything else weird. But I
Speaker 1: would love to get to know what's inside a black hole.
Speaker 1: I don't know about visiting one, or seeing one, or
Speaker 1: getting too close to one and getting shredded, and desperately
Speaker 1: want to know what's inside a black hole. Maybe side
Speaker 1: will find my marbles lost for sure. All right, thanks
Speaker 1: everyone for listening to Daniel and Jorge explain the universe.
Speaker 1: Thanks for listening. Do you have a question you wish
Speaker 1: we would cover send it to us. We'd love to
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Speaker 1: us to feedback at Daniel and Jorge dot com