What are Gravitational Waves?

Published Oct 9, 2018, 9:00 AM

What does it mean for gravity to make waves? How do we see them?

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Okay, Daniel, is it possible for Einstein the famous scientists to be wrong?

Well, I got a lot of crackpots in my inbox every week claiming have proven Einstein wrong, because it's every physicist's number one fantasy to prove that the most famous scientists of all time could have made a mistake.

Well, I have the prof here for you. I heard that Einstein he was right about a lot of things. But I heard that he predicted that we would never see gravitational waves.

That's right, and then scientists actually found these crazy little features at the universe.

So he was wrong, right, I mean technically he was wrong in that he predicted that physicists could improve him. Right.

Yeah, it's a small victory, but technically we've proven Einstein wrong.

Will take it, We'll take it.

Hi.

I am Jorjank and I'm Daniel. Welcome to our podcast. Daniel and Jorge explain the universe Now. I am a cartoonist.

And I'm a particle physicist.

I draw comics called PhD comics online.

And I do research at a large Hadron collider, smashing protons together to try to figure out what the universe is made out of and explain it to you.

Yeah, we just like talking about this crazy stuff that our universe is made of and how it works.

We basically think of what could people out there be interested in? What kind of questions is an everyday person had about the universe, And we thought, let's dig into that and explain.

It to be On the program, we're going to talk about gravitational waves.

What is a gravitational wave? That's today's topic.

What are they? How wavy are they? And will they make you gravitationally seasick?

It's a grave topic too.

It's a grave, grave topic.

This topic we hope won't put you in your.

Grave, that's right, It will make you feel lighter.

Actually, even though it's a pretty heavy topic. You probably know what gravity is, You probably know what a wave is. But we went out in the street and we asked people do they know what a gravitational wave is.

Here's what they had to say, A wave of gravity kind of like how it acts on people. The only thing that I might think, I guess is gravitational waves is because something that's reflected from the sun.

No, I've heard of gravity, not gravitational way.

I'm not sure. Yeah, okay, so most people have heard of the word gravity. That was encouraging. That's good.

That's encouraging from your like a general sense of what do people out there know?

Yeah, yeah, you know, like it's not well, it's kind of an interesting concept because it gravitational ways. It's like two things everybody knows about gravity and waves, and it's like you put them together. Suddenly it's this whole new thing nobody knows about.

That's right, And frankly, it surprised me how little people knew about it, because some people had heard of the topic but knew almost nothing. Some people really had no idea what it was. But for me as a physicist, this is something that made a huge splash in the physics community. It made enormous waves. Jokes aside when it was discovered a few years ago. I mean, it's the kind of thing where they discovered it and almost immediately won the Nobel Prize for it. That's a big deal.

Yeah, But I guess the truth is that I had never heard about it until the big discovery was announced, you know, and I'm pretty sort of plugged into research and physicist, but no, I had no idea what these things were until I started hearing from physicists like, hey, we think there's a big discovery about to be announced.

That's right. There were rumors bubbling around for a while. But I don't think you're unusual. I think before the discovery, nobody outside of physics had really heard of gravitational waves, and even most people inside physics thought it was kind of a crazy backwater subfield that might not ever amount to anything. But once it happened, there's this huge splash and publicity and everything. You'd think it's spread around the world and everybody would remember. But I guess it's faded. Maybe if we'd done this a couple of years ago, just after the announcement, people might know more or remember more, or at least be better at pretending they knew something about it, right.

Right, or maybe it's just kind of a reflection of how we're all trapped in our little bubbles these days. You know, like what feels like a huge deal that it's all over the media to us, Maybe somebody who lives in another media bubble has it doesn't make it to them, you know.

Yeah, yeah, maybe. Well. One of the fun things about these interviews is hearing people try to figure it out as they're talking to me, you know, like, hmm, maybe it has something to do with the sun, or like it has waves on people or something. I think that's pretty insightful for some psychologists to dig into.

Right, And it's been a big deal in the face community for a while. I mean, this is the project that discovered these gravitational waves a few years ago, LIGO, that's been going on for years and years. It's what it's like, one of the most expensive physics experiments ever, right.

It's been going on for a long time. It's not one of the most expensive. It's only six hundred and something million dollars. Oh my god, I can't even say.

That for a laptop to a particle fis I know.

I mean from the point of view like the LHC which is ten billion. Yeah, this is a pretty cheap experiment. But the amazing thing is that it's been going on for decades before it got results. I mean, they've been working on this since the seventies and eighties and they've been getting funding with no discovery for decades. That's the kind of crazy blue sky research that I think is wonderful, but it's happening less and less these days.

Well, let's break it down. What is a gravitational wave?

Right, So a gravitational wave, simply put, a gravitational wave is a ripple in space. Right, Space itself is not emptiness, it's not the backdrop of the universe. It's not nothing. It's a physical dynamical thing. It's like we're fish swimming through water, right, and space is our is our water. And so it turns out because space can do things like bend and expand, it can also ripple, and so a gravitational wave is a ripple in space itself.

So like if you were a fish your whole life and you were just moving through water, you wouldn't think of the water as a thing. It would just be the thing you're moving around on the right.

That's right. You might not even notice that it's there unless it did something or had some effect on you, right, And so if you're a fish, you notice, oh, look there are currents, and I can serf those or whatever. And so we're starting to notice that space is doing some stuff, and that's what makes us pay attention to it.

Okay, So gravitational wave is a ripple of the space itself, like the space itself we're in actually kind of ripple.

Yeah, And I think people might have an easier time understanding ripples if they start first by thinking about other things that space can do, which are similar, like space bending. So space is three dimensions, yeah, that we know of, right, that we know of, yeah, down, forward, backward, left, right, But it's hard to imagine space bending in three D, so it's easier to think of it in two dimensions. So typical examples think of like a big rubber sheet, that's space. Well, space can be bent when you have big heavy objects sitting on it, like a like if you put a big bowling ball onto a rubber sheet, it's going to distort it. And then if you, for example, if you roll a marble across that sheet, it's not going to anymore move in a straight line. It's going to move like in an orbit, or if you've ever spun a coin down one of those crazy parabolic things in a museum and then it seen it do crazy orbits. Space gets bent by mass, and that's what makes things go around the Sun, for example.

So space is not like a flat, stiff sheet. It's like this kind of wobbly kind of thing that we're rolling along in.

That's right along it. We're moving in what seems like the most natural path, the straightest line for us, unless you get pushed in some direction. But if there's a big heavy thing near us, like the Earth or the Sun, pretty big massive stuff in the universe, then it bends that space and affects sort of the natural straight line we would travel in. So people can practice thinking about space bending by understanding how big heavy masses can distort space, affecting the way that we move through it, and the subtle bit there is in the rubber sheet analogy. The two dimensional rubber sheet is bending into the third dimension, right, which doesn't exist in the two D rubber sheet universe, but in the full three D example and the real universe that we're in, our space is not bending in some hidden, higher fourth dimensional universe. The bending is intrinsic. It's the relationship of objects in that space. If you want to ask, like, what's the shortest distance through space for these two points that's affected by this bending of the space between them.

Oh, so it's kind of like the relationship between things in space is what's changed, what's getting distorted.

Exactly the relationship between things in space. And when I first started thinking about this, like space as a thing, even as a physicist, it's pretty hard to think about because you imagined space as being defined by distances or as you say, like the relationship between things. And so I always wondered, like, how could you even tell if space is bending? Because wouldn't your rulers bend? Also, like don't you need some like absolute external yardstick to notice if space is bending?

But you would notice it, wouldn't you. Like if I'm near a distorted space and I take my rule ruler and I point it one way, I would measure something differently than if I pointed in another way.

Yeah, exactly right. And that depends a little bit on how your ruler is built, Right, If your ruler is built out of molecules like most rulers, and those molecules have a distance between them that's fixed by like their you know, the forces between them, like you know, a standard wooden rulers held together by chemical bonds. Then those bonds are going to be stronger than like any space stretching, and so a ruler like that is not going to be affected by space getting stretched, and so it would certainly notice. But say, for example, your ruler was like a bunch of equidistant pebbles floating in space, right, then if space stretched, you wouldn't even notice because the distances between those the pebbles would grow and shrink as well, and you would have no comparisons.

So you mean, like if you if you measured distances kind of like they do in my home country of Panama. It's not like you look it up in a GPS map. It's more like, Okay, you go down this street and then you make a ride at the McDonald and you make a left at the gas station, and that's how you get to my house. Then if like the terrain change, I wouldn't notice a difference because I would still use these landmarks.

Still get to McDonald's exactly. You still take a ride yeah. Yeah. So if it's like an earthquake and suddenly McDonald's much further away, it's still like, you know, it's one McDonald's away. Still right, Well, this is a perfect spot to take a break. We'll be right back. With big wireless providers, what you see is never what you get. Somewhere between the store and your first month's bill, the price you thoughts you were paying magically skyrockets. With Mint Mobile, You'll never have to worry about gotcha's ever again. When Mint Mobile says fifteen dollars a month for a three month plan, they really mean it. I've used Mintmobile and the call quality is always so crisp and so clear. I can recommend it to you. So say bye bye to your overpriced wireless plans, jaw dropping monthly bills and unexpected overages. You can use your own phone with any Mint Mobile plan and bring your phone number along with your existing contacts. So ditch your overpriced wireless with Mint Mobiles deal and get three months a premium wireless service for fifteen bucks a month. To get this new customer offer and your new three month premium wireless plan for just fifteen bucks a month, go to mintmobile dot Com slash Universe. That's mintmobile dot Com slash universe. Cut your wireless bill to fifteen bucks a month. At mintmobile dot Com slash Universe, forty five dollars upfront payment required equivalent to fifteen dollars per month new customers on first three month plan only. Speeds slower about forty gigabytes on unlimited play. Additional taxi s, fees, and restrictions apply. Seement Mobile for details.

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So space is this squishy thing that we're living in. It's not like a big vacuum or an empty warehouse. It's like this squishy thing and it's going squish by things that are heavy and that can affect how far things are apart from each other. So now a ripple is like what is that?

Then?

Like a ripple in water? Is it similar to like a ripple? Like if you fish, is a ripple grifftage and wave like a ripple in the water. You know, like there's an explosion underwater, we would feel that sort of shock wave.

That's exactly what it is. Yeah. And so if you have two really heavy objects, for example, spinning around each other, or one really massive object that's accelerated, the gravitational field from that object is going to change really quickly. Right. So you imagine a static object is a gravitational field around it. If that object accelerates or moves really its velocity is changed really quickly, then the gravitational field itself is going to change, and the wiggle in the field caused by the acceleration of that object is a ripple. Right, It's going to travel through space outward from that object. So imagine you take like a rock. It has a gravitational field. A rock is going to be bending space around it. And then if you move that rock, something far away is not going to notice instantaneously that you move the rock. It can't tell that the gravity has changed yet because the information about the rock moving travels at the speed of light.

Wow, So even gravity can only move with the speed of light.

That's right. Everything in the universe that carries information can only move at the speed of light or slower. And so for example, say the Sun disappeared magically, the Earth wouldn't notice for eight minutes. What because that's how long it takes for light from the Sun and for the gravity from the Sun to reach us. So the path of the Earth wouldn't be effected for eight minutes.

So there'd be eight minutes where there was no Sun, but the Earth would just keep going like, hey, we wouldn't see it gone either, right, because the light would also take eight minutes to get here.

That's right. The Sun could have disappeared five minutes ago. We would have no idea. Don't rush outside and look at the sun. Everybody, please don't know.

I'm scared of Daniel.

Anyway, in that scenario, there's nothing you can do in that scenario, so there's no point in preparing for it.

Okay.

But the point is that the gravitational information moves through space the same speed everything else does.

And so if something is changing really quickly, then that like increasing gravity decreasing gravity would sort of travel would take a while to get to me, and I would see that as kind of a wave, like a ripple.

Yeah, exactly. Imagine somebody's turning the Sun on and off. It exists, it disappears, it exists, it disappears. Then the gravitational fields of the sun, this bending of space is going to disappear and then snap back and disappear and snap back. And what we would see it or on Earth, is gravity turning on and off and on and off, and those would be enormous ripples in a gravitational field. Yeah.

Wow, Well, I think what's cool is that, you know, everyone talks about it like it it has to be like two black holes or something huge and massive, But it's really like everything generates gravitational waves, right like you and I. If I move my arms back and forth, I'm generating gravitational waves.

That's right. And you happen to be a very magnetic person or a gravitational person, so I sense those waves from your hoe head.

I'm glad you didn't say heavy, thank you.

I know I was about to say that. I was trying to steer clear of it. Yeah, you're right. Everything that has mass bends space, and anything that has mass and is accelerated will be generating gravitational waves. But the thing for people to remember is that is super duper crazy, ridiculously weak, which is why, for example, if you're sitting next to somebody in a train, you don't feel a literal gravitational force between you. There is one there, but you can't even sense it because it's so tiny compared to the gravitational force of you and the Earth.

No matter how attractive that person is.

That's right, you might be feeling other forces, and you know, feel free to act on that or not not. Yeah, to you, there's no physics advice about whether or not to approach people on a train. But your point is correct. Everything is generating gravitational waves that has mass and is accelerating.

Right, but they're so weak.

Yeah, you need something really really huge in order to be able to detect them.

Okay, well, let's talk about how we even came up with this idea of a gravitation wave. Right. Who sits around thinking, hey, I wonder if ripple, if gravity and space time itself can generate waves.

Well, your first guess would probably be right in that case, because the first person to think about that was Albert Einstein, Right, everybody's go to scientist. In this case, it is exactly right. He came up with this theory of general relativity, and the core idea in that theory is that gravity is not a force but a bending of space. And so a very natural consequence of his theory was that if things accelerate, then it would make these ripples in the bending of space, and those ripples he called gravitational waves.

Oh, I see. It's like, once you come up with the idea that space can bend that, and that also this information about space bending can travel faster than light, then your naturally are left with the idea that you can have these waves traveling through space for gravity.

Yeah, exactly. But a funny wrinkle in the story, or ripple in the story, if you like, is that Einstein he thought about these things as sort of a theoretical possibility or an abstract idea. But he I think he wrote in his paper. He's like, he said, but we could never discover these because they're too small. Even Einstein, who predicted these things, thought it would be impossible for us to ever detect them, which is like even more kudos to the experimentalists or proving Einstein wrong by proving him right.

Wow, So even Einstein didn't think that it would be possible to measure these but they've done it. They did it a couple of years ago.

Yeah. And you know, there's one way in which I personally agreed with Einstein because I remember when I was choosing where to go for graduate school, I was visiting various institutions and thinking about what physics they were doing, and I went to Caltech and Caltech was one of the leading institutions on LAGO, and I actually got to talk to one of the leading scientists on it at the time. He was telling me about this project and I thought, Wow, this sounds cool but really hard and basically impossible, and that would be crazy to sign up to do a PhD on this. Wow, I thought, they're never going to see these things. It's impossible and ridiculous. More power to you, but I'm going to go do particle physics.

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The skill of the problem is insane, right like it's first of all, you need something momentous happening, like two black holes spinning around each other so fast and I'm just about to like crash together, right.

Yeah, really really massive objects. And you need a lot of acceleration also, as you say, for example, black holes smashing into each other does that. And the reason is that the very last moment before the black holes collide into each other, they're moving super fast. It's a huge acceleration there.

Oh, because you know, we think of black holes crashing like they're traveling the straight line and they crash into each other, but they don't, right, They actually kind of get close to each other, and then they start circling each other, and then that circling gets smaller and smaller and smaller and smaller.

Yeah, exactly, they spin around each other a little bit, unless you build like a black hole collider to shoot them exactly at each other. And you know, anybody out there who knows how to do that, give me a call. But if two natural black holes that approach each other are going to already have some relative angler momentum, so they're going to keep that relative spin from each other. So they're going to keep that and then they're just going to spin around each other. As you get closer and closer to have the same angler momentum that you're going to have to go faster and faster.

Kind of like when you flush the toilet. You know, two things floating there spin around each other, and then as to get closer and closer, they start spinning really really fast.

Yes, exactly, the dark matter in your.

Toilet, the other from the black hole.

Yeah, exactly, it spins around each other. I was going to say, more like an ice skater spins around faster and faster as she pulls her arms in. But yes, also dark matter in your toilet does the same thing.

Yeah, and then right before it flushes down, it's spinning so fast. That's when these generates massive gravitational waves. Right, that's the idea, that's right.

So jorge'es takeaway from this topic is every time you fluck the toilet, you're generating gravitational way which is through, which is technically accurately true. Yes, yes, yes, and you have a physicist now on record saying that. But in the case of the cosmic toilet, you know, and black holes actually swish around each other and flesh themselves away. What happens is you get these ripples, and when the ripple passes through Earth, it squeezes the space in one direction and stretches it in the other. That's the effect of the ripple on Earth. So if we want to see it, we have to have a very accurate ruler pointing in two directions, one ninety degrees from the other, so we can see a squeeze in one way and a stretch in the other direction at the same time. So the direction of the wave tells you where it was coming from. Also, and you want to calibrate yourself by having measurements in the direction of the wave and ninety degrees. Also, because you don't know which direction a wave is going to come from, you want to make sure to be sensitive to it no matter where it comes. So you have two basically really careful rulers that are ninety degrees or arrange from each other, so you can be sensitive to any direction.

But it's crazy because even though these are generated by two colliding black holes, by the time they get to is these waves are like really faint, right.

Yeah, there really are tiny. I mean Einstein had a good point. In order to see these things, you have to see space shrink by one factor in ten to the twenty, right, that's ten with twenty zeros after it.

It's like if you had a meter stick those ten to the twenty meters long, you would have to see a shrink by one meter.

Yeah, exactly, yeah, Or if you wanted to see something shrink by like a millimeter, you'd have to have a yard stick. That's like, you know, ten six tillion meters long or something crazy. It's really ridiculous. It's like the size of our solar system, right, yeah, I think so. And so you can imagine not only is it really hard to see things that are small, but other things are affecting you. Right, not that anything else is shaping space that same way. But if you have a ruler, how do you even know how long it is to ten to the twenty right to one part in ten to the twenty. How do you detect when it's wiggling? Like if you just heat up your ruler, it's going to get a little longer, if you cool down your ruler, it's going to get a little shorter. So the experimental trouble of seeing something so tiny is really really it's really difficult and It's really an amazing coupde gra that they pulled it off.

So it's like if I was standing on one end of the solar system and you were standing on the other side of the solar system, it'd be like asking, like, hey, Daniel, did you feel the space between us showing by one millimeter exactly? That's crazy.

It's pretty crazy, and so in order to do it, they had to come up with some pretty crazy technology. The way they do it is really awesome and beautiful. I mean, there's fascinating theoretical stuff, but the experimental side of it I love also because they had to come up with new techniques that nobody had ever used before.

So this is the LIGO project, right l I GOO.

Yeah, that's right. LIGO stands for laser interfer Metric I think gravitational observatory LEGO.

Not to be confused with LEGO.

That's right. Lego's almost as expensive as LIGO. But the way they do it is they have these two rulers that are four kilometers long each, and they shoot a beam of laser light all the way down this tunnel and then it bounces off a mirror and comes back, and they do that simultaneously along both legs, and then when the lasers come back, they can tell how far the light went by comparing how many wiggles it's made.

Oh, it's kind of like a relay RaSE, right, Like you send a laser beam out and then you measure how long it tastes for it to come back, and that's how you know how far it went.

Yeah, but you don't need to measure the time because lasers are light and lights has wave like properties, and so it wiggles. So if you send out two beams of lasers and then at the same direction and they bounce off mirrors and come back, they're going to be wiggling all the way there and wiggling all the way back. And when they come back, they should be the same place in their wiggle, right either up or down. And if they're in the same place in their wiggle, they'll add up together. If they are opposite places in their wiggle, like one of them went a little bit further and now instead of being in the upwiggle, it's at the down wiggle, then those two will add up to be zero destructive interference. And so that's the interferometer part of the experiment. Is that they send out these two pulses of lasers and when they come back, they see are they interfering positively by adding up on top of each other or interfering negatively by canceling each other out. They're interfering negatively. It means one of them wiggles a little bit longer than the other one were a little bit shorter, and now they're out of sync.

I see. So it's not like you're measuring whether the distance in one direction change. You're measuring whether it change relative to the other direction exactly. And that's what these ways do. They shrink space in one direction and stretch it in the other.

Direction exactly, And so that's what you're looking for. And they actually have multiple observatories. They have one in Louisiana and one in Washington State, and they're finishing one or just finished one in Italy, and they're building other ones around the world and the idea and they're all pointed in different directions and there are different locations, so you can use those multiple telescopes to tell you like is it real, you know, or is it just like a semi truck driving over it, which is shaking all of my mirrors. And you can also do it to tell like where did it come from? Because if it landed in Washington before it landed in Louisiana, then you can tell which direction it came from. You can use it to sort of triangulate.

It's interesting how the word telescope changes, right because of physicists. Right, like people think of a telescope as this tube that you look through to tell how far ships are away from me or something, or how far land is. That's a telescope. And nowadays telescope in science way means you know, it could mean a giant antenna, or it could mean like an array of antennas, or it could be like these crazy long laser tunnels spread all over the world, Like you call that a telescope.

Yeah, well, I think telescope. I'm not a linguist, but I think telescope essentially means seeing far away, and so you can just generalize it to mean we don't have to see only with light, right, we can see with other things. And so you're right, And I think that's an awesome use of the word telescope because as we invent new kinds of technologies and new kinds of telescopes. It gives us other ways to look out into the universe. Right, and you know, we're in this tiny little dot in a corner of the universe, desperately drinking in the information that the universe is sending to us. It's wonderful to imagine. Can we have another way to listen to the universe? Can we have another way to get information about where we are and what's going on around us?

Well, that's what people say. It's so significant about the discovery of gravitation ways is that it gives us another way to listen to the universe. Right as people say that it's like a new way of listening to the universe.

Yeah, that's right, and it is amazing and dramatic. A couple of quibbles though. Sometimes people say it's the first time we have another way to listen to the universe. Right, They say, forever we've been doing astronomy using only light, and now we have a second method. It's not exactly true, because we also have particles. For example, we've been using neutrinos to look at the universe, and we've been detecting neutrinos for a while now. So it is true that we're adding to our tool belt by adding gravitational waves, and it's hugely important and fascinating, but it's not the first time we have a new tool in our LIU.

So primarily before the only way we even know about the rest of the universe or what's going on is by the light or the particles that come to us.

Yeah, the photons from stars and from other galaxies. Yeah, it's all been photons.

Like the radio waves. Those are all photons and light, different kinds of light. But now in addition to particles and light, we have this other way of like knowing what's going on elsewhere in the universe, which is these gravitational waves.

And it's really important, not just because it's ooh cool, new shiny tool, which is fun, but because gravitational waves can do things if particles can't. Right, gravitational waves are not moving through space, so they're not like blocked the way things move through space, are right, There's no dust cloud that can block a gravitational wave.

They don't get like attenuated if they hit a big black hole or something.

Well, they can be they attenuated the further way you are, right, Like everything else, they spread out through space and they get weaker and weaker, but they can't be blocked by matter. I mean they can get they can if you have another gravitational wave, you can they can get reflected or distorted or something. But it penetrates through things which are otherwise invisible to us and can send us messages from inside things that otherwise would be opaque to us. And so it's a really powerful, fascinating new tool. It really is like we're opening up a new kind of eye to the universe for the first time. One of the other crazy things about gravitational waves is that we had no idea how often they came. Right. One tricky thing is can you see them at all? Right? The second tricky thing was are there any anyway right? It could have been that we're really good at seeing them. We developed this amazing technology. We're super sensitive to these tiny little effects. But they only come once every one hundred years.

You mean, like the kinds of events that would generate them in a large enough way for us to detect may not be happening as often as we think, Like these black holes crashing into each other, with these nutron stars flushing down the toilet. Maybe these things were.

Rare right, Yeah, we didn't know, right, but the first time that they turned on the experiment with the new powerful capability. They've been incrementally improving it for decades, but when they first got to the place where they thought, okay, now we really think we can see them, they saw one within like a day of the first time they turned it on. It was incredible.

Wow.

And now they've been seeing many, many, many. They have like a huge pile of these things they've been studying. And so that's really exciting because it could have been that you turned on this new telescope in the universe, so it's just really quiet and there's nothing, didn't really have anything to say, But it turns out it's got a lot to say. And these things happen more often than people hoped.

And so now we can learn more about like things like black holes crashing, right and nutron stars crashing and what happens in those like extreme moments of physics.

Yeah, yeah, exactly. So I think one of the really exciting things is that we have this new eye on the universe, this new way to look at the universe. And in addition, there's cool stuff to see. Right, So one of the cool things they saw recently was not just two black holes colliding, but two neutron stars colliding well. And the fascinating thing about that is that they saw through the gravitational waves and at the same time they saw through telescopes using normal light, So they could see these two things happening through two kinds of vision overlaid on top of each other. That was really pretty awesome.

Yeah. I like the way they always describe this project, which is which is very poetic. I feel like it's like they always say, imagine if your death your whole life. I mean, you could look around you, but you could hear anything, and then all of a sudden, somebody gives you the ability to hear stuff, and so now you not only can you see stuff with light, but you can also kind of hear them through this whole other channel.

Yeah, there's some poetry there. Sometimes I think they take it a little too far because in science communication articles about this, they often describe this as listening to the universe or and you can hear the chirp, you know. I think that gives people the impression that gravitational waves are sound, or that colliding black holes make a sound. Remember that space is quiet sound can't go through space because there's no air. So these are gravitational waves, and you can take the frequency of those waves and transform it into sound waves and listen to it, the way you can take the frequency of anything and transform it into sound waves. Like people took the Higgs boson events and transform them into sound waves, and you're like listening to the Higgs boson. I don't really think you're listening to the Higgs boson, so you're not really listening to the universe. But poetically, I agree, it's another way to get information from the universe. Yeah, it totally works as an analogy, but I think some people think it's literal, and I just want to make the point that it's not literally listening to the universe.

These are gravitational waves, not sound waves, although they kind of propagate in a similar way right.

Well, in the same way that waves do propagate, But you know, water waves are compression waves through a medium and gravitational waves are ripples in space, and so it's a little bit different. But the analogy is very, very useful as long as you remember it's an analogy. Don't stick your ear into space and expect to hear gravitation always, Yes, not a good idea.

Yeah, I know. It's like it's very poetic. It's like, all of a sudden you can hear and suddenly you're hearing all these toilet flushings across the cosmos. It's very poetic.

Yeah, exactly, listen to the universe flushing away. It's waste.

Well, on that note, thank you very much for listening. I hope you guys enjoyed that discussion.

It's a pretty heavy topic and I hope we handled it with gravitas.

Yeah, I hope you didn't get gravitation. Elise back. All right, Well, thank you very much. Have a great day. Guys.

Do you have a question you wish we would cover, Send it to us. We'd love to hear from you. You can find us on Facebook, Twitter, and Instagram at Daniel and Jorge one Word, or email us to feedback at Danielandjorge dot com. When you pop a piece of cheese into your mouth, you're probably not thinking about the environmental impact, but the people in the dairy industry are. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. How is us dairy tackling greenhouse gases? Many farms use anaerobic digestors to turn the methane from manure into renewable energy that can power farms, towns, and electric cars. Visit you as dairy dot COM's last sustainability to learn more.

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Daniel and Jorge Explain the Universe

A fun-filled discussion of the big, mind-blowing, unanswered questions about the Universe. In each e 
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