Listener Questions 3

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Speaker 1: Hey, Daniel, if you are the dictator of a country, what would you do in terms of science? In terms of science, I think I'd like to explore, like, what is the biggest cookie that's possible to be you can still be tasty. That's something physicists wonder about. I wonder about that because you know, a cookie is a complicated thing. It has to be crispy, has to be soft on the inside. You make it too big, then it's I'll just gonna be gooey. How do you get the heat dispersed? It's a hard physics problem. So you think you need to all the resources of a country to figure out the answer to this question. Hey, if you're gonna do something, do it ten billion dollars big right. That's the way I rolled the ten billion dollar cookie. That it would be your science project, your dream science project. How would you would you? Would you aim higher? I would probably do just make sure everyone understand science. You know, for all that money to educating people about science, you should fund like an awesome podcast about it. Yeah, oh man, you know, and maybe like get two people on it and two really good looking at people. We eat a lot of cookies with stay trim anyway. Yeah, and then just give them the ten billion dollars. I'm sure they'll be responsible with it. Yeah, totally, not spending on cookies or anything like that. That's right, that's right. Hi. I'm Jorge. I'm a cartoonist and the creator of PhD Comics. And I'm Daniel. I'm a particle physicist by day in a podcaster by I don't know afternoon, and I'm a big fan of cookies and science. And welcome to our podcast, Daniel and Jorge Explain the Universe, a production of I Heart Radio in which we look around and wonder what is weird, what is amazing, what is crazy about this universe, and then we talk about it in a way that we hope you will understand. And we're also the authors of the book We Have No Idea, a Guide to the Unknown Universe. So if you would like to hear more from us or learn more about all these great and amazing questions about the universe, go check it out. That's right, and we also love to hear from you about your questions about the universe. At the end of every episode we tell people please write in if you have something you'd like to hear us talk about if you have a question you can't quite figure the out the answer to, just using Google send it to us will break it down for you. And a lot of people write us, right Daniel, And we get a couple of a dozen a day. Right, Oh yeah, we got a lot of nice emails, and some of them are just appreciation people saying, hey, thanks for the show. We're enjoying it. It is wonderful to read. And then people send us their crackpot theories of the universe, like, hey, I figured out dark matter, and you know quantum gravity, and you know why airline food tastes so bad? All with my one theory? Daniel, Actually that that one was for me. What do you mean it's a crack poc? Didn't you read it? I read all the theories that people send us, sometimes everything carefully. Sometimes I skimmed through them, I'll admit, but I do love reading them, and I love getting people's emails, and mostly I love the emails where people ask questions. When people say, here's something I don't understand, something i'd love to figure out. Could you please explain something to me? Have you ever got a question that you had never thought about before? Oh? For sure. Yeah, lots of questions people ask I had never heard before. I never even thought about, like how to answer that question before. Those are my favorite ones, and so Daniel will answer your emails. But every once in a while we have an episode where we answer your questions on the podcast, and today is one of those episodes. Can I tell you about one of the questions that we got that totally blew my mind? Oh? Please? Somebody wrote in and said, what if the sun is actually a giant banana wrapped in hydrogen gas? Think about it? Think about it? So I did that. I thought about it. You know, Yeah, that's a fascinating idea. I've never thought of that idea before. I've never answered that question before. I don't know how to answer that question. So I thought, maybe you're the banana expert. What would be preventing the sun from being a banana wrapped in hydrogen? What would exploding hydrogen? Well, I guess it'd be like a roasted banana, right, because it's pretty hot there. So if you like, you know, banana's flambay and then maybe they'd be good. But I'm not sure how you would assemble all those hydrogen atoms and fuse them in the right way, they get potassium and all that stuff to make it into a banana. So I think that was not a sincere question. Is maybe actually a joke aimed at you. But technically is it possible, like um, you know, just out of random you know, fluctuations, somehow a banana forms for an instant in time, So it could be true. Yes, And in fact, if you believe in the multiverse, then there is some universe in which the Sun spontaneously forms a giant space banana in its core for you know, for an instant. Yes, yeah, there you go, There you go, And that's the universe I want to live in. We live This is an aspirational podcast, folks. We talked about the universe we live in, in in the universe we wish we lived in. That's right. And the answer is always in the multiverse, anything is possible. So technically you can be optimistic about anything, even space bananas. That's right. I feel good, people, because it's all possible. It's all possible. And so today on the podcast will be tackling listener questions. Some of them are questions that I get a lot, and I thought people might be interested to hear the answer. Maybe other people have these questions. Some of them are questions I had never heard before and had to do a bit of research, So mix it up a little bit. Yeah, and so today we have some pretty exciting questions. We have a question about a giant space gun. We have questions about photons, and we have questions about why isn't everything exploding? Or is it? Or is it? So we'll get into that today. So buckle up, folks, it's going to be a crazy ride today. So today's first question comes to us from Paul, and Paul had a question about how is there a better way to get to space? So here is Paul's question. Hi, Daniel and Jorge. When I was a kid, I remember reading in an old Guinness Book of World Record about a gun in Barbados sticking fire sixteen inch shell weighing about three hundred and thirty pounds to an altitude of two hundred and fifteen thousand feet. Now that's less than half of the lowest orbital altitude, but that was fifty seven years ago. So ken a gun put an object into orbit? And if so, why aren't we doing it? It has to be cheaper than rockets. Thanks all right, thank you Paul for that awesome question. This has the distinction to be you're the only person to ever write in asking that question. Really, it's not a it's not it's not a branding question in the in the public's mind. Apparently not. Not everybody is thinking about what they could launch in the space using a really big gun. But I love the end this question when he says, if we can do it, why aren't we doing it all the time? I mean, if this is within our grasp, man, I would be like shooting banana pies into space all the time. I think, I think. I think it's interesting because that the corollary to his question was what he was sort of really asking was isn't this cheaper than rockets? Because really, it seems anything should be cheaper than rockets. That's true. Rockets are not cheap, right, and so a lot of people spend a lot of time thinking about other ways to get stuff into space because rockets cost millions and millions of dollars, right, Yeah, So the question really is like, can you build a giant space gun? And and that's how you put things into orbit. You just shoot them out as super fast and up. I guess vertically up is how you would do it, or maybe not, and then that would just go off into space. It wouldn't stop, would go into space and get into orbit. That's the question, right, Yeah, that's the question. And let's unpack it a little bit because there's a couple of problems with this idea. First is just stting it up high enough, right, Like can you shoot something from the ground and make it all the way into space? Right? And if you just want to leave the Earth, it's a whole separate question of could you shoot something from the ground and get it into orbit. But let's just say you want to escape the Earth, you're on a mission, you want to flow down into space, and you just want to leave Earth's gravity, right, meaning shoot something with a gun and not have it fall back down exactly. Yeah. So the question is then how fast does it have to go? Right? That's called the escape velocity of the Earth. And the escape velocity of the Earth is really high, like if you're gonna leave the surface and not get any more pushes, right, Remember, a rocket gets continuous pushes. It brings the push the pusher with it as it's going up in the air, keeps getting more and more pushes keeps accelerating. Yeah, so you're going to get all that push in the very beginnings. You have to have your maximum speed is immediately after you leave the gun because you're gonna lose it pretty quickly. So then the question is how fast you have to be going to leave Earth's orbit? Okay, so like what's your the initial velocity you need to have in order to keep going on into space and not fall back down. That's right, exactly. And on the surface of the Earth, the escape velossity you'd need is about eleven kilometers per second, So in one second you'd have to be going you have to cover eleven kilometers, yeah, exactly. And you know, for scale, that's like thirty three times the speed of sound, so you know, like jets can go like Mack one, Mack two, Mock three. This is mock thirty three. Wow. How much is that in in miles per hour? In miles per hour, I think that's like twenty five thousand miles per hour. Wow, So that's a pretty big h I think I don't think that my prius has enough digits. I think in its digital readA. Yeah, I don't think the digits is the problem with your prius. But that's exactly the problem. Like number one is how do you get something going that fast? Right? Like shooting stuff from a rifle doesn't get anywhere near that speed. Um Like rifles can. They can shoot a bullet fast in the speed of sound, but not thirty three times the speed of sound. So you need a really big gun. You need a lot more explosive to get it up that speed. I say so, even if you take a rifle and point it up and you shoot, the bullet would eventually come back. Now, do not do that, Yes, do not point a rifle straight up, because that bullet will come right back down at you or the guy standing next to you. This happens every year in New Year's Eve. People fire guns into the air and you think, like, where do you think those bullets are go? And they're not going into space, not into space, not into space. Then they're coming back down and maybe hurting somebody. Um, So do not fire bullets into the air. Um, they will not go to space. And the other problem is say you did manage to shoot a gun, or you know, you had some payload and you shot it at this incredible speeds, had enough energy well, it's not easy to go through the atmosphere at that speed. What happens when you go through the atmosphere at high speeds is friction from the air air resistance, So you heat up, just like you know how spaceships when they land, they have to come through the atmosphere, and you know there's all that fire and burning and stuff. That's because of the friction with the air. So this way, you'd have so much speed, you'd have friction on the way up. Oh so it's kind of like the re entry problem, but in reverse exactly exactly, it's the re entry problem on the way out. So if you build like a three million dollar satellite and then want to launch it into space when you don't want it's going twenty five thousand miles per hour through the air because it'll melt. What have you put shielding on it, you know, like they do with the Shuttle and the landers. Yeah, but the Shuttle doesn't re enter the atmosphere twenty five thousand miles per hour, and that's on purpose, right. It slows down a lot, and it does it very gradually, so you need a lot of shielding. And then this thing we get heavy and then it gets more expensive and you're gonna get this thing. Plus it's shielding up to twenty five thousand miles per hour. It's not easy. Start to imagine that cold air can burn you to a crisp right, Yeah, we'll imagine it's sandpaper. Right. Imagine if somebody's gonna you're gonna do you're you have one of those bananas slipping slides in your backyard, except instead of slippery plastic, somebody puts sandpaper. Right, that's what it would be like. Yeah, that is a horrific scenario, Daniel, and trying to raise it from my mind there, right, Well, that is why we don't do this. I mean there's other problems too, right, but that's those are reasons number one and two. Reason number three, this is why we don't go on slip and slides of miles per hour, saying it's everything feels like sandpaper miles per hour. That's the point. Okay, So it's really hard to do just to just to accelerate any kind of mass or object up to twenty miles per hour, and also it would burn up with air. So what are some of the other problems. The other problem is getting into orbit. I mean, what we talked about just now is getting it out of Earth's atmosphere and out of Earth's gravitational pull. That's actually harder than getting something in orbit because you have to go higher. Right, So you might think, well, what if we just wanted to go into like low Earth orbit, we didn't want to actually leave Earth, And you think, well, that might be easier. It's true, but you can't actually shoot something from the ground into orbit. You cannot. You cannot because remember you're shooting it, you give it one push, right, You can't land in a stable orbit has a fixed trajectory, and that trajectory includes intercepting the ground, so eventually it will re intercept the ground. The way to get into orbit is you fly up into there and then you adjust your speed so you have the right speed and direction to be in orbit. But there's no way to get there from the ground without additional pushes once you're up in the atmosphere. But you're saying, is it you need minor adjustments once you get up there, or you need like a lot of adjustment. No, it could be fairly minor adjustments. So, like one scenario is you have stuff on the ground and you shoot it up to fairly low Earth orbit or just below using your massive space gun that you built because you're a dictator. And then you have something catch it something in low Earth orbit, like catch it and then readjust it and shoot it out into orbit, so that that kind of system might work. But you can't just shoot something into orbit from the ground because no, no trajectory that starts from the ground will lead to a stable orbit. Like I know, if you're a Superman, you could not put a football in orbit, no matter how hard you try. That's right, that's right. And and football and even Superman, if he threw a football thousand miles per hour, it would melt right, like unless it's a super football from his original planet or something. Yeah, kryptonite football, that's right. But then he couldn't hold it, Yeah, exactly. But that's just a detail. The thing is and and and Paul mentioned this in his question, is that people have tried this right, People have worked on this problem. People have shot stuff pretty far up, so you know, people are not daunted by the fact that this seems impossible slash in practice. Well wait, didn't they do the math? Yeah, you know, but these are dictators were talking about and so sometimes you know they are not bothered by math. You know they rules don't apply to them. These are autocrats we're talking about. Math is just fake news, all right. So that's a that's a pretty amazing thing to learn that people have tried this, and they both people who have tried it are are sort of pretty notorious. Yeah, this is not a community of folks you want to go to conferences with. Because the first person to really do this significantly was Hitler. And Hitler had this cannon called the V three cannon, and he could launch projectiles and nine away. Again, the Germans were also working in rocket technology, but this is just launching it from the ground with no more pushes. Well, I was wondering when our discussions would eventually devolve into talking about Hitler. So everything on the internet gets compared to Hitler eventually, right there, eventually here we are. Um, so he tried, he tried to build giant cannon that would launch things into space. Yeah, and I don't think his goal is to get into space. I think his goals be able to like launch shells to France from Germany, right, they want to like really long distance bombardment. I think that was their goal. I don't think they cared that much about shooting stuff into space. Oh I see, just like, what's the biggest, uh missile you can build? Yeah exactly. But it inspired another guy, a guy named Gerald Bull, and he convinced some combination of American and Canadian governments to give him a bunch of money for something called Project Harp, which is basically, build a huge gun and see if you can launch stuff into space. And he didn't do a terrible job, really he um. He came up with a pretty good name, Project Card, Project card project, that's build a giant gun and she takes into space. Project crazy dictators fund this, yeah exactly. So how far did he get? Well, his record still stands today. He shot a four hundred pound object a hundred and ten miles above the Earth's surface, so that counts like he got something into space. Now it came back down. It didn't escape the Earth, right, he shot it up and it came back down. But that's the record today for in terms of launching something from the ground and not giving it any more pushes is a hundred and ten miles. How did he do it? What? What did this gun look like? It just looks like a really big gun. I mean, it's just like a really big tube. I mean, there's not a whole lot of cleverness here, right, It's just a big twoe but a big explosive in it, you know. And the question is can you get enough money to build a bigger, bigger and bigger gun. And you know, some of these things don't scale that easily, and the strength of the cylinder, etcetera. You have to take into account. But basically it's just spend more money, make it bigger. It's kind of like particle physics, right, Spend more money, make a bigger accelerator. I guess. The idea is that you sort of make a like a rocket, but instead of having the propellant in the fuel on the rocket on the missile, you just keep it on the ground exactly, you know what I mean. Like, that's what a giant gun solves, is the idea that you don't need to bring the fuel with you. You just exploit it all here on Earth and then that sends you into space. That's right. The problem with the rocket is you're not just lifting your payload, you're lifting the fuel. You need to lift the fuel. You need to lift the fuel, etcetera, etcetera, so it gets by the time you're actually launching your fuel. So this solves that problem by basically blowing up all the fuel at once on the ground and seeing how far it goes. Right. Um, but it does really solve the problem. I think a more clever idea is like laser supported rockets, like shoot the energy at it using beams basically so you don't have to transport the fuel. You can send it up from the ground as it goes wow, and shoot it with lasers which would absorb the late and they would absorb the laser and redirected to their propulsion. Yeah exactly. I mean if I was a dictator and I was funding crazy science projects getting stuff in the space, I would definitely put some money in laser propulsion. You're like, I'm not going to be one of those crazy dictators and build giant gun. I'm just gonna be a dictator that makes giant lasers. Yeah exactly. Um, But the story doesn't end there. This guy Gerald Bull, he ran out of money from the U. S. And Canada and didn't finish his gun, but then he sold the idea. He sold the idea to Saddam Hussein right to what Yes, inspired by Hitler and then employed by Saddam Hussein, and he said, look, I'm gonna build you the biggest gun ever. And I guess that sales pitch worked. You know, he must have a killer powerpoints slide deck, and he was building the mother of all guns. Had three words, biggest gun ever. And it's just like I wanted. Um. Yeah, And so he was in the middle middle of building the biggest gun ever. Like I think Saddam called it the mother of all guns. And you know, Saddam probably had the same idea that the Hitler had, like I launched shells to Israel or launch shells to anywhere in the Middle East or something nefarious. Um. But the Bull was actually assassinated by we don't know who, um while he was working on the project. So it didn't end very well for the scientist. Wow. Yeah. And that's a movie or a comic book right there, Yeah, exactly. Ben Affleck is probably writting the screenplay as we speak. Yeah, he's the CIA agent task with assassinating the Big Gun. So Gerald Bull got a bunch of money from Iroq, but he never matched his original high score that he did on his own using Project Harp. So that stands today, um so and miles is the record. I don't think it's a practical way to launch things because remember the kind of things we want to launch in a space are usually delicate, right, tele communications, satellites or people, um, and you've got to be pretty careful. So the rocket approach is much more gentle because you never achieve as high as speed. Interesting, so putting it, putting your delicate object on top of like tons and tons of explosives not recommended. That's the safest way to do it in a rocket, Yes, that's that is the safest way to do it. Gradually blow up all those explosives, right, don't blow it up all at once on the ground. All right. So that's the answer for Paul. Can you shoot stuff into space using a gun? That's the question. The answer is, um, technically yes, but it's but it's really hard, not a good idea. And also you can't put it into orbit. You need something else, that's right, Yeah, you need another stage, I mean to catch it and redirect it or something once you get up into orbit. Yeah. And also for Paul, stop trying to make this gun because they're going to assassinate you. Little little pro tip there from your podcast. Also, funding from dictators doesn't always end out well. All right, thank you, Paul. And so we have two more questions about particle collisions and about dark energy. But first let's take a quick break, all right, Daniel, So today we are answering reader or more more like listener questions, questions that are listeners out there sentence and so we answered one about building a giant space gun. And so our second question comes from Jacob, and Jacob has a question about your job, right, Daniel's Hey, Daniel and Jorge. I was just wondering how you guys isolate and manipulate the particle or particles that you use for the large Hay John collider. Thanks. That's a great question, right, He's asking us like, how do you get one particle into the collider and slam it into into the other particles and how do you control them and manipulate them. It's a great question, yeah, because, um, you know we know that in a particle collider you're smashing particles together, and so I guess, I guess the question is how do you how could you possibly get two of these particles to hit each other right on the head. That seems like an impossible problem. It is an impossible problem. And that's why we don't do that because that's basically impossible, right, Yeah, you don't. You don't. You don't aim one particle to hit another particle. No, that would be really hard. It's like, imagine you're like throwing a water balloon from l A and somebody else that throwing a water balloon from New York, and you have to have them like meet somewhere over Kansas. Right, that's basically impossible. But wait, wait, what if you used a space gun? Totally will work. Absolutely, a water balloon will survive miles per hour, no problem, a space a potato gun, or a water builon gun. Yeah, now, the it's a good question. That's impossible. And so it's also very hard to just isolate individual particles. I mean, there's a whole field of physics that works on that, atomic molecular optics and stuff like that where they trap individual particles. But that's really hard to do. Um And so what we do instead is we don't send individual particles flying against individual particles. We send a little gas of particles like a bunch of particles against a bunch of particles coming. The other direction is that the official physics name bunch of a bunch. We actually use the word bunch, and the reasons you use, yeah, exactly, bunches. You can look it up at the lhc UM and um. The reasons for that are is that even if the particles do hit each other, the chances of a collision are not great, like mostly they just you know, gently brush off each other. So we want, actually, is a bunch of collisions happening at the same time, so that you have a higher chance of seeing something interesting. Plus it's just hard to get it, so even if you so, even if you could align one particle and aim it directly at another particles, they might not collide at all. Yeah exactly. I mean what do we really mean by a collision? A collision is an interaction. We think of collision is the edges of two things hitting each other, right, because we're used to macroscopic objects. But in that case, you know the zoom in macroscopically and think about what's happening when the two edges touch. What happens really is that the particles in one push away from the particles and the other. That's an interaction, that's like a force. So now strip that all away, and you have just two particles pushing against each other. Right if they're going really really fast, unless they hit immediately right on each other, then they'll just whizz right by each other. Um And even still, even if they go they go right on top of each other. It's quantum mechanical, and so sometimes just nothing happens. Most of the time, very little happens most of times. The thing that happens is boring is that the two particles just like slightly deflect. So what we want to see is the rare stuff at times when two particles smashed together make something weird and crazy nobody's ever seen before. So to make that happen, we have to send a bunch of particles in at once. But what's the difference between them interacting and not interacting? Do you know what I mean? Like, how do they decide? Or is it just that they're more head on than others and or that they have no other option but too smushed together or what? There's a real quantum mechanical mystery there, because you know, quantum mechanics tells us that you can repeat the same experiment. You can like shoot two particles exactly the same angle at each other the same way and get two different outcomes. So you're asking, like what determines whether they interact or they don't, or that the interaction is a boring one or an interesting one. It's random, Like there's somewhere in the universe a die gets rolled every time these two particles collide. That determines like are they going to bounce off each other gently? Are they going to create a Higgs boson? Are they going to create something else these folks have never seen and blow their minds, or are they just gonna miss? And so the strategy you guys use is to just go of the numbers. You just throw a whole bunch of the particles. You don't try to hit individual particles together. You just throw a whole bunch of them together, and you hope that you get some of them hitting each other exactly. It's like you're looking for your first job, and so you send out like thousands of resumets, right, you know, just email one resume and then wait a week, Right, you send out a lot of resumes and in our case, like my faculty search when for a professorship, exactly right, you go for the numbers um. And so in this case, we have ten to the eleven protons and every bunch that's a hundred billion protons in a little bunch, and they're all in a really small space, right, yeah, exactly, and we focus them using magnets. So the other part of his question was like, how do you control them, how you maintain them? Basically, use magnets because you can't, like you can't have a little zip block bag which just tend to the eleven protons in it, you know, you carried around. So we have a magnetic bottle. Essentially, we use magnets to keep these things moving in a circle. Right. Magnets bend path of a charged particle. So we focus that using magnets, and we get it down to um two and a half micrometers. Right, So we we want to we want as many protons as possible and as small as an area as possible, because it's the greatest density, the greatest possibility that something exciting is going to happen. So, and you might think, well, that's a lot of particles, right, it is, but it's also a small number right, like you know UM a mole, which is you know the atomic unit as UM you know is Avogadre's numbers like tend to the twenty three particles, right, And a really really good vacuum has tended to twelve particles in it um per cubic meter. So tend to eleven particles is a lot if you just count them. But it's also it's very diffuse, right, it's not. It's not like this is a very dense thing. This this this bunch of protons and you you don't just send one bunch at a time, You send a whole bunch of bunches at each other. That's right. It's organized like a Swiss clock, which makes sense because it's a huge circle in in in Switzerland. Geneva up, and we have more than two thousand bunches in the accelerator at all times, and you know, the thing is like tens of kilometers around, and so they're all synchronized, and so every twenty five nanoseconds, one bunch hits another bunch, and then nanoseconds later, another bunch is coming down the line and they collide. And so it's just like all day, all night, every five nanoseconds, we collide one bunch of protons against another bunch of protons. It's like a ferris wheel, but instead of each pod, you have twenty eight hundred bunches just going around and around. Yeah, first world makes it sound like it's all fun, enjoy, but these guys are slamming into each other. It's uh, it's like an assembly line. You know, they're just coming down the line and getting smushed into each other. Um. And also you can reuse the bunches, Like the bunches passed through each other, some tiny fraction that maybe interact, but most of them are untouched, so you can send them through again, so they go through each other and then they just come back around again. Yeah, exactly, you don't discard them. Yes, when we come out, it's called to fill. We fill the accelerator. We put all these bunches and we get them going. We slam into each other and then you know, eventually you lose some of them because you can't have perfect containment um and so the the effective number of collisions you're getting starts to drop. So then you empty it and you refill it start again. All right, Well, so that answers Jacob's question the he has how do we control how do you control the particles in the collider, and how do you get like single particles who hit each other? And the answer is using a bunch of bunches. Yeah, exactly. So we don't throw one water balloon at another water balloon. We throw like a hundred billion water balloons at a hundred billion water balloons, and then we have it's so so much fun. We just get to watch what happens. We like, you know, create explosions and watch them all day long. Best job in the world. Okay, here's here. Here's a question. Then for me, um, what if you aimed this collider into space, would you get the proteins up into space into proteins are definitely moving fast and to escape Earth velocity, but the atmosphere would stop them because they would slam into other particles and they would, you know, very quickly, so one proton would hit another proton, and then those two protons would share the original protons energy to have two particles at half the energy, and then you have four particles at accord of the energy, and eventually you have a trillion particles at a trillion the energy. But some of them might make it out into space, right, Yeah, some of them might bleed out over the edge of the atmosphere. But you wouldn't have like you know, you're imagining like Superman rocketing from the surface of the Earth triumphantly, arm raised, Right, that's not what would happen. You just gently heat the atmosphere, basically. Yeah, but some of them might leak out into space, Yeah, exactly. Some of them might leak into space, but not into Earth orbit. Got it, Got it? All right, Jacob. Hope that answered your question, and so we'll we have one more question about the exploding universe, but before we get to it, let's take a quick break, all right, Today we're answering listener questions questions from you, the listeners of this podcast, and so our third question of the day for this episode comes to us from someone in Dallas. Hi, Daniel and Jrge. This is Tom from Dallas. I love the show and always leads me to more questions. And one thing that I've been really grappling with is the expansion of the universe. Right, So, if the entire universe is expanding faster than the speed of light because of dark energy, and it's not expanding from a central point, but rather from all points in spacetime simultaneously. That wouldn't everything just kind of be exploding around us? How do I even exist? If I'm imploding at faster than the speed of light? I don't feel like I'm imploding Anyways, Guys, I really appreciate you taking my question, and I really enjoy the show. Thanks for everything you do. Yeah, I love that question. Um, I love he had his mind blown. You know that he's thinking about this cosmic sized questions he wants to understand. And that's my favorite thing is when you can get you can give people a piece of information that they didn't know about the universe, and then they try to fit it into their brain. They're like, Okay, if that's crazy thing you just said is true, then why doesn't this happen? Why doesn't that happen? And that's physics, right, that's like how do I reconcile this thing with all the things I know? And so I love seeing people do that. They're basically being physicists. Yeah, I feel like we're doing our job. If it makes people think and have their own questions, that's right. Not if we're making people worried that they're exploding. But you know, it's a good it's a good question to ask. They are their minds are exploding, their mental consciousness, their connection to the universe. Yeah, yeah, exactly, And it's a great question. And I think the question comes from hearing that dark energy is expanding the universe, right, stretching it out. Yeah, because we had an episode where the tide of the podcast episode was is the universe exploding? And we said at the end that yes, the verse that's right, the universe is exploding. And um, I think a lot of people are tempted to think about that like an explosion which has a center. Right, you blow up a bomb, things fly out from the center, and so you imagine, oh, the expansion is happening from the center, things are getting pushed out. But we we made the point in that episode, which is true, that that's not the way it's happening. That dark energy expands all of space. So every point in space is being affected by dark energy. New space is being created all the time, everywhere. Right, It's like the dark energy is not just acting in the center of the universe or at the end. It's like all the way through there's just a little bit of dark energy that's pushing everything apart. That's right. And it also it sounds really violent because we say that dark energy is you know, almost three fourth of the energy of the universe is dark energy, So it sounds like maw and this must be a really powerful force. It's pushing galaxy is apart, and galaxies have hundreds of billions of stars, So what could possibly have the energy to push those apart? And if that's applying to me too, if you could push galaxies apart, why isn't just just shred me like tissue paper? Right? I think that's the essence of the question. Yeah, And in particular, he said that if we are if the universe is expanding faster than the speed of light, how is it that we don't feel it right now? Like? Why why isn't my um hand moving away from my other hand at the speed of light? If the whole universe is expanding faster than the speed of light. Yeah, yeah, it's crazy. Um Well, the answer, the thing to understand and to grapple with this question is that dark energy is the most powerful thing in the universe in that it has the biggest slice of the energy budget. But remember the dark energy is everywhere, right, Most of the stuff in the universe is not everywhere, like the matter in the universe is clumped up into stars and galaxies and it's in most of space doesn't have matter in it. Right. Dark energy doesn't work like that dark energy. She's uniform. It's spread equally everywhere, So it doesn't have to be very powerful to add up to a really, really really big number because most of the places where there's nothing, there's dark energy. Do we know that for sure that dark energy is evenly spread out, it's not at all clumped together or in in you know, imperceptible clumps. That's right. We know very little about dark energy, but that's the model that fits the data. That dark energy is expanding the universe everywhere. And we again, we don't know what dark energy is, right. It's really just a description to the fact that the universe is expanding. But it's consistent with something which is a property of space, meaning that it's uniform. It's everywhere, you know, whether you're in the middle of a star or you know, in the middle of one of our listeners, or in the middle of one of these huge voids in the in the super supercluster sheets and bubbles. Right, it's everywhere, Right, it's like a it's like an even glow that the universe has exactly, And because it's everywhere, it's not really very strong anywhere. Okay, So, yes, it's creating new space between our galaxy and other galaxies, but there's a lot of space there, so it adds up. Right, it can have a big effect, but between like your hand and the your other hand, there's not a lot of space. So it is creating new space there, but it's very weak compared to the other forces at play, namely the chemical bonds holding your body together. Right. The reason that you don't fall apart is that the stuff in your body is holding onto the other stuff in your body, and those bonds are more powerful than dark energy. Right. But you know, I think Tom was maybe wondering how it can be that the universe is expanding faster than the speed of light, but yet you don't feel it here. Yeah, Well you don't feel it here because it's a very small effect here, right, Like it's it's creating a very small amount of space per space, and that adds up to making things, to creating space faster than light can travel. Right, Like, imagine all the space between here and another galaxy. So every piece of that space increases by one per cent, and then another one percent, and another one percent, and it's increasing at a rate that that it's faster than light can go through it. Remember, nothing can go faster than light through space, but there's no limit to how fast you can create space. So all those little bits of space between us and that other galaxy are working hard enough to create more space than light can fly through. I was thinking maybe a good analogy was that, you know, if you grab a rubber band or a strip of rubber band and you stretch it. You know, the ends of the rubber band can be moving really fast relative to each other, but if you're somewhere in the rubber band, you wouldn't feel the stretch that violently. Yeah, I think that works, except you know, we don't know if the universe has an edge, right, But if you just pick two points, right, like two galaxies, you can think of them as the edges of the rubber band, and uh, and all the space between them is like the rubber bandy part of the rubber band, Then yeah, I think that works, right, because the distance between the two alexis is the sum of all the increasing distances um and the little bits of space in between. Right, yeah, yeah, So dark energy is there, is out there, it's everywhere in the universe. It's also inside you. And the reason that like isn't ripping you away from the Earth is that, like the force of gravity is strong enough to keep you on Earth. The force of gravity, even though it's so weak, is stronger than dark energy is right here, right, Dark energy, remember, is very weak on a local scale, but only only great when it adds up over huge pieces of space. So you're like you're in one point of the rubber band and the ground the ribband is stretching a little bit, but you're keeping yourself together stronger than the rubber band is stretching you at that little point in the band exactly right, Like if you're you know, you're it's a windy day and somebody's getting blown, but they can grab onto something, right, You can grab onto a pole or to your friend or something. You can overcome the power of the wind just by holding on. Right, It's the same thing. Dark energy is just like wind, expanding everything in space, but it's it's a bit of a gentle ease, and so it doesn't take that much of a force to overcome it. And that's why, for example, our galaxy is not getting torn apart, right, the space between galaxies is increasing. Why isn't our galaxy getting shredded? The reason is gravity. There's enough gravity in our galaxy to hold itself together to battle dark energy. We don't know how long that's gonna that's gonna be the case because dark energy turned on like five billion years ago and started expanding the universe. We don't know why. We don't know how long it's going to keep going. We don't know if it's going to increase the intensity of the expansion or stop and turn around. We don't really know. So we'll forever be weaker than you know, local gravity and local chemical bonds, and we don't know. It could be in the future it's much more powerful and it shreds everything, right, or it could turn off and get board and go do something else. Looking forward to that all right, So Tom asked, why isn't dark energy exploding everything, even the things around is? And the answer is that it is. It is exploding everything. That's right, You've and you, Tom Boom, we just literally blew your mind. But we use the word exploding and the word faster than the speed of light kind of when a universe skill, right, like, on a universe scale, it's sort of exploding. And the ends of the university, if there are ends, or two extreme ends of the universe, are maybe moving faster than the speed of light relative to each other. But on like a local, little tiny, hey my house scale, it's not such an incredible effect. Right, Well, those ends are not moving faster than speed of light relative to each other, but space is being created between them faster than light can move through it, which is a slightly technical difference in the way you say it, but yeah, exactly, yeah, okay, alright, cool. So those are three awesome questions, mostly from the Southern United States. That's right, randomly selected, but this time they mostly ended up from the southern US. But we get questions from all over the world. So if you're a listener from a far flung place, please send us your questions, or if you just have a burning question about something in the universe and you'd like us to explain it, please write it in. I love getting your emails. Yeah, so please send them into questions at Daniel and Jorge dot com. Well, thanks for listening. We hope you guys enjoyed that. Tune in next time, and if you're a dictator of a country with a billion dollar signs budget, consider investing it in a podcast or a giant space gun using rubber bands to fly protons into outer space. There you go, give this man some money that I will agree with. See you next time. If you still have a question after listening to all these explanations, please drop us a line. We'd love to hear from you. You can find us at Facebook, Twitter, and Instagram at Daniel and Jorge That's one word, or email us at Feedback at Daniel and Jorge dot com. Thanks for listening, and remember that Daniel and Jorge Explain the Universe is a production of I Heart Radio. For more podcast from my Heart Radio, visit the I Heart Radio, a Apple Podcasts, or wherever you listen to your favorite shows.