Daniel and Kelly’s Extraordinary Universe - Great, Big Questions about the Universe

Episode Date: September 26, 2023

Daniel and Jorge answer questions from young people about the Universe, to mark Jorge's new book!See omnystudio.com/listener for privacy information.

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Like on Fridays when I take your questions for the BAQA. Whether you're trying to invest for your future, navigate a toxic workplace, I got you. Listen to Brown Ambition on the IHeart Radio app, Apple Podcast, or wherever you get your podcast. Hey, Jorge, if you had to leave a Yelp rating for the universe, what would you give it? Can I give it like a trillion, trillion stars? I think that might break their database, but I'm guessing you're saying that the universe is,

pretty great. Yeah, it's pretty great in a lot of ways, right? You mean great as in it's awesome? It's awesome and it's also really big. It's a great big universe. Hey, that's a catchy phrase. Yeah, somebody should use it for the title of a new book. That's a great big idea. Hi, I'm Jorge. I'm a cartoonist and the author of the new book, Oliver's Great Big Universe. Hi, I'm Daniel. I'm a particle physicist, and I also think the universe is pretty great. And big. It's a great big universe. Great also means big, doesn't it? Or isn't that part of the etymology of great?

I think technically can mean several things. Like, it's great, like you like it, but also like it's great, like it's big. Yeah, like Great Britain, right? It's pretty great. And also big. And pretty British. But anyways, welcome to our podcast, Daniel and Jorge Explain the Universe, a production of iHeartRadio. In which we try to accomplish a feat, which sounds impossible to download the entirety of this great, big universe into your mind. To summarize all of the whizzing and banging and frothing and towing of the tiny little particles that make up this universe into a mathematical story that somehow makes sense to these grown-up apes. That's right, because it is a great big universe full of amazing facts that we like to talk about here on this podcast.

and also rate, I guess, with stars. The universe is definitely filled with stars, big, glowing stars, and also, you know, blowing up pop stars. Well, hopefully, I'm not literally blowing up. But it is filled with stars, planets, asteroids, galaxies, dark matter, dark energy, and also people young and old. We're here to ask questions and also sometimes answer them about the universe. That's right. We think everybody should be curious about the universe.

When you stare up at the night sky, we want to know what makes you wonder, what questions do you have about how it all works, not just the earth that's under our feet, but the whole big, great universe out there. Yeah, and speaking of Great Big Universe, we are here to celebrate the release of my new book called Oliver's Great Big Universe, which is out now and you can go out and buy it. Yeah, congratulations. Tell us a little bit about the book and why you wrote it. Yeah, it's an awesome book.

It's maybe the only book that is endorsed by Jeff Kinney, the author of Diary of a Wimpy Kid, and also Carlo Rovelli, the theoretical physical physical physical. That's quite a collection. Do you have to be a cartoonist or a theoretical physicist to read it? Absolutely not. I actually wrote the book for kids who wouldn't normally pick up a science book. And also for anyone out there who's interested about the universe. Yeah. Tell us a little bit about your approach. How do you attract people who aren't usually into science? Well, the book, again, is called Oliver's Great Big Universe. And it's about the story of this 11-year-old kid named Oliver, who one day decides he wants to be an astrophysicist. But of course, being 11 years old,

He doesn't quite know what that means. And so the whole story is about him trying to figure that out and also him explaining to other kids all of these amazing facts about the universe. So there's chapters about black holes. There's a chapter about dark matter and dark energy. There are chapters about the planets and there are chapters about the time as well.

And don't you, by coincidence, have an 11-year-old named Oliver? Yes, it is not a big coincidence. So the whole book was kind of inspired by my son when he was in fifth grade. he came home one day and at the dinner table he announced he wanted to be an astrophysicist and so we were like do you know what that means and he's like I have no idea and so yeah that all sort of like confidence and chutzpah and curiosity is kind of what

inspired the whole book so what's it like when a cartoonist has his son say I want to be a physicist is that like when a physicist has a son who says I want to be an artist yeah kind of you're going to go no no it's cool he's always been kind of a science kid he's always been interested in science. He's in the math team. He's in the science Olympics team. And so it wasn't super surprising that he says that he wants to be an astrophysicist. But it's pretty cool. Yeah, we try to encourage it for sure. Awesome. Well, something we encourage in our podcast listeners and their kids is asking questions, is thinking about the universe, is wondering if they want to be an astrophysicist when they grow up and what exactly that entails. And step number one of being an astrophysicist is just

looking up at the night sky and wondering what's out there. How does it all? work. What is in our great big universe? Yeah. And so to celebrate the release of the new book, we are answering listener questions from kids today. That's right. I went out there and asked our listeners to ask their kids what questions they had about the universe. And so today we'll be tackling a few of those. That's always a risky thing to ask your kids what kind of questions they have. Or did you make it specific about the universe? I made it specific about the universe, which makes it totally generic. Yeah, I guess the universe is everything.

Even the uncomfortable parts. Ask me a question, but only about anything in the universe. Right, so we have several questions here from kids about all kinds of things about the universe, from suns and black holes to the infinity of the universe. So the first question comes from Violet. Because the sun is still a star, winter one day collapsed like other stars and turn into a black hole.

That is a deep question. From a small mind. I love, even in that brief question, you can hear her train of thought. She's connecting our star to other stars. She knows that other stars collapse into black holes. And then she was reflecting that knowledge back here and wondering about the fate of our star. I love all the connections she's making, all the physics you can hear happening in her brain. Yeah, it's pretty awesome.

And the sun is something I think all kids can relate to, right? I mean, everyone sees it every day. Maybe not directly, but we're all basking in its light. I don't know. She sounded like she had an accent. She might not see the sun that often out in Great Britain. It's pretty cloudy. Well, some parts of it are sunny, aren't they? Let's hope so.

I do have a whole chapter in Oliver's Great Big Universe about the sun, which it's a nice coincidence. It's kind of fun to explain it in terms that kids can understand. And so let's dig into Violet question here. She wants to know if our son is going to collapse into a black hole because I guess she's heard that other stars collapse into a black hole. Yeah, there are a lot of black holes out there. sort of two varieties. There are the kind at the center of galaxies, which are called supermassive black holes, really, really big ones. And nobody really knows where those come from. It's kind of a mystery. But then there's lots of smaller black holes out there which come from stars at the end of

their life, these stars that have collapsed into a black hole. And so she's wondering about those. And black hole is the end point of some stars. Not every star is going to end up as a black hole. And to understand why some stars become black holes and others don't, you have to understand something about the balance of forces that are keeping a star burning in the first place. Yeah, I guess it's a big point to know that not all stars are the same. They're all different and they mostly differ in size, right? And like the amount of stuff that's in it. Yeah, stars come from the collapse of a big cloud of dust and gas that forms a denser blob. But a cloud can sometimes make lots of stars and you can get smaller stars or more massive stars.

It depends a little bit on the configuration and whether there was like a supernova. a shockwave that triggered it and whether you had like a cluster of heavy metals in the center to gather stuff more rapidly. So there's a big variation. The bigger stars are less likely and they burn hotter and shorter and the smaller stars are much more common and they can burn for a long time. And as you said, it's kind of a balance of fusion and gravity. Like there's stuff exploding in the middle, but there's also gravity trying to squeeze the whole thing down, right? Gravity is what gets things started. You tug a little pebble here and a little bit of cosmic dust over there, and then you get this runaway effect where it gets stronger and stronger gathering stuff

together. And if there was only gravity, then any accumulation of stuff would turn into a black hole because it'd be nothing stopping it from getting infinitely dense. But there are other things in the universe than just gravity. Like the Earth doesn't collapse into a black hole. You don't collapse into a black hole because your body or the Earth's structure is strong enough to push against that gravity. Gravity is a huge force in the universe, but it's not very powerful. So it's not actually that hard to overcome. Yeah, but on a sun, what keeps the whole sun, the whole cloud of gas from collapsing is fusion, right? It's the nuclear reactions that are happening in the middle. Exactly. We call it radiation pressure. That fusion is like an

explosion. It's shooting out photons. It's pushing out on all the stuff and that balances the gravity of the star. It's sort of amazing that those things can be in balance and be in balance for so long. Stars can burn for millions or billions. We think some small ones might even burn for trillions of years. It's an incredible balancing act. Yeah, it's pretty wild even now that I think about it to think that it is stable, right? Like it could have been the case that suns and stars are not stable. They could either fizzle out pretty easily or maybe they could have blown up more easily. Exactly. And if you get a star that's big enough, like more than 300 times the mass of our sun, then it gets so hot and so intense at the core that it really does blow itself apart. They don't

last very long. There's an interesting range of masses. As you say, the initial scoop of stuff that you get really determines the outcome. And I guess we're just kind of lucky that there are lots of stars that can burn long enough to make our universe bright. I guess they're sort of like candles, right? Like a candle burns for a long time because it has this kind of balance that it can burn, but it can't burn too much or too fast. Exactly. That's why you like to build a candle instead of a bomb, right? It'd be hard to light up your home with bombs. Right. I don't recommend anybody reads Jorge's new book by the light of bombs. Please get candles if you don't have light bulbs. Yeah, yeah. Or flashlight as well. That works. It's a little safer. Exactly. But it's not just radiation pressure

that can keep something from collapsing into a black hole because eventually that radiation pressure gives up. When you've burned up all the fuel in your star, when you've turned all that hydrogen into helium or something heavier, then you're not fusing anymore. But even still, not every star that finishes all of its fusion will turn into a black hole. Right. Like you need to have a certain amount of mass to your star for it to even have a chance of becoming a black hole. Exactly, because there are other forces that can push back against gravity. Like you can make something really, really dense like a neutron star, which can have like

the mass of the sun with a small radius of just kilometers. And even that is very dense, has a lot of gravity, but there are nuclear forces there. The strong nuclear force is pushing back and preventing it from collapsing into a black hole. So even if you don't have fusion pressure from an active star, you can still avoid collapsing into a black hole just from the chemical forces or the strong nuclear force. forces. Right. Now, Violet's question was about our son. She's wondering if our son will one day collapse into a black hole. And so what's the answer? Yes or no? The answer is almost certainly no, but there is still a lot of uncertainty in exactly how much mass you need. As you said,

if you have enough mass, then you have enough gravity. You can overcome all of these forces, eventually the fusion force and the strong nuclear force, and you can collapse into a black hole. But we think that the threshold is somewhere around 10 times the mass of the sun, though it's something we understand in great detail and the sort of the consensus number has been moving around a lot wait what you mean we don't know for sure if our sun is going to collapse into a black hole we don't know absolutely for sure but it's very very unlikely the smallest black hole we've ever seen is just over three times the mass of the sun and it probably came from a star that was more like 10 or 15 times the mass of the sun

some calculations say you have to have 20 25 times the mass of the sun but by looking at black hole mergers. We learned a lot about the sort of minimum black hole mass. It's a lot of interesting stuff still to be learned about this question. But Violet, don't worry, we think our son is safe. Which means we're safe and she's safe. Although, of course, even though the sun won't turn into a black hole, that doesn't mean it'll be a fun place to live in about five billion years when it expands into a red super giant and fries the earth. Boy, way to set her at ease there. We just answer a question and she's like, and then you drop

the bomb. Well, you know, budding astrophysicists got to learn that the universe is a scary place. But the basic answer for Violet is that our sun doesn't have enough mass, we think, to ever collapse into a black hole. So what's going to happen to our sun is just going to keep burning forever? It's not going to burn forever. A lot of helium

will accumulate at its core, which will move the burning more to the exterior, which will puff up the sun, so it'll grow to be a super giant, a big red star, then it'll blow off its outer layers, and they'll leave behind a hot core. So probably the sun will become a white dwarf, which basically just means it leaves behind a big blob of hot metal.

Yeah, it'll just be sort of like a big ball of metal glowing in the dark. Yeah, exactly. Well, hopefully by then, Violet will have invented a war drive or something, or a wormhole maybe. The violet sounds pretty smart. And by then we'll be expanding into other solar systems. That's right. or a whole generation of astrophysicists inspired by your book will save humanity.

Yeah, and then I'll get all the credit, right? And the royalties, right? You get some of those patents, right? Yes, I'm going to say yes, and then have the lawyers figure it out. All right, well, let's get to more questions from kids about this great big universe. But first, let's take a quick break. Your entire identity has been fabricated. Your beloved brother goes missing without a trace.

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I ended up having amputation below the knee of my right leg and the traumatic brain injury. because I landed on my head. Welcome to Season 2 of the Good Stuff. Listen to the Good Stuff podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. Now, Danny, what kinds of books did you read when you were a kid? Did you read any physics books?

Hmm. Oh, great question. When I was 11, I was definitely reading a lot of science fiction books. And I definitely watched a lot of like Nova and documentaries on TV. And I gobbled up like big picture books with drawings with artist's impressions of black holes and stuff like that. Yeah. And so today to Mark, the release of the book, we're answering listener questions and specifically from kids. And so our next question comes from James and his dad. Hi, Daniel and Jorge. This is Paul from Manchester in England. My son James likes thinking about the implications of an infinite universe. In particular, he has this idea that in an infinite universe, anything that could possibly have happened must have happened an infinite number of times. He was talking to me about this recently, and it led me to wonder whether we can say that if the universe is infinite,

it must not be possible to make a machine to travel cosmic scale distances very quickly. Because if it was possible to build such a machine, then in an infinite universe, an infinite number of alien civilizations would have done it, and our planet would inevitably have been colonized by aliens. James and I look forward to hearing your thoughts on this. Thanks very much. Oh, my goodness.

Just get James to write his own book. What an awesome idea. Can we just give him a Nobel Prize? A Nobel Prize for arguing that a breakthrough is not possible. A Nobel Prize just for blowing my mind. What an interesting question. Yeah, it is a really ingenious idea. All right, so let's break it down.

So I think James is saying that if faster than light travel was possible and the universe is infinite, then by now some alien civilization with faster than light travel should have visited us by now. Yeah, I think that's the argument. It's sort of similar to saying if time travel is possible, somebody in the future would have discovered it and then come back to visit us. And so since they haven't, therefore time travel is not possible. Except in this case, he's reflecting the argument into space and imagining somebody out there must have figured out faster than light travel. And if they had, they would have come visited us.

And they haven't, so therefore maybe it's impossible. Right. What do you call that kind of argument? Is there a name for it? Clever. Clever. Argument from desperation. I don't know.

And I've heard this argument before. Like there's no time travel because otherwise there would be. time traveler is visiting us right now. But I always feel like that's assuming we live in an interesting time. But if there's an infinite future for humanity, then somebody will find us interesting, right? Well, I feel like it's sort of like if you're in a really bad place and you're like, there must not be any tourists in the world because we never get tourists here. That really just says something about where you live.

But if there were an infinite number of tourists, somebody would think that your boring street was fascinating. I think that's the crux of his argument. I mean, it really relies on this idea of infinity and the power of infinity. Right, right. Unless you live in an infinitely boring place in which case it cancels out. What's infinity divided by infinity? Theologians have been thinking about infinitely powerful forces and infinitely strong walls,

but you're thinking about infinitely boring places and infinite numbers of tourists. Yeah, you know, that's what this podcast is all about. Great big ideas. That's right. Well, there's a lot of really interesting ideas in James' argument. The first one is essentially that if the universe is infinite, anything that can happen will happen. And that's how he gets the idea that if faster than light travel is possible,

somebody out there will develop it. And that's a subtle idea, actually. It's pretty interesting, right? To think there might be an infinite number of alien civilizations. And if it was possible, one of them must surely have invented a warped right. Yeah. And if you take it literally, it doesn't just imply an infinite number of alien civilizations. It implies an infinite number of human civilizations.

Right? Because if humanity can evolve, which obviously it can because it has, and space is infinite, that would suggest that it's happening somewhere else, actually an infinite number of times. But do they have to be humans? Couldn't they be like tentacled aliens that invent the warp drive? No, they don't have to be humans. I think it's actually weirder if there are more humans out there, totally independently evolved than like weirdly tentacled aliens. Although technically in an infinite universe, wouldn't you also get an infinite number of human civilization? Yeah, exactly. You get an infinite number of everything that's possible. And virtually possible because we're here. Yeah, exactly. So you would have an infinite number of James is asking an infinite number of questions on an infinite number of podcasts. All right, so then how would you answer that, or how would you break down the infinity argument?

I think it's a pretty strong argument, but there are some holes here, some nuances. And one is on the issue of infinity. It's true that anything with a finite probability will happen an infinite number of times if you get an infinite number of tries. Like if you have some huge dye with a billion sides to it, it doesn't really matter how many billion sides there are. If you get to roll an infinite number of times, eventually every side will come up. So that part is true. But when you apply that to like anything could happen in the universe, there's a little wrinkle there, which is that you need the right initial conditions. Imagine an infinite universe, for example, that's just smooth and has no features, no structure to it, no stars ever form, no galaxies ever form. That's,

That's an infinite universe, but you don't get every outcome because the outcomes are determined by the initial conditions. You have to have the right configuration for things to start from, which determines essentially what is possible. Yeah, I guess you have to assume that the rest of this infinite universe is just like the universe that we see around us, which may not be the case. Which may not be the case, exactly. But you could also imagine that maybe in order to develop faster than light travel, some alien

civilization needs a very different set of conditions than the kind we have. here near much stronger curvature so these aliens grow up with a native understanding of space time and can therefore manipulate it maybe they need to be like a planet inside a black hole right it's possible inside supermassive black holes to have stable orbits and people have speculated you could have life evolve inside of it but a species that evolves inside a black hole they couldn't even use their FTL travel to reach us whoa but i think that doesn't affect james's question right Like, we know that the conditions around us are possible. I think it's true that if the universe is infinite and filled with infinite stuff, there's

an infinite number of human civilizations and maybe also infinite alien civilizations. But it might be that FTL travel is possible, is allowed by the laws of physics, but that none of the infinite number of human civilizations discover it, either because the conditions in which we grow up, in which we evolve, don't give us a sort of natural intuition to manipulate space time because we're like not near enough black holes to experience that. Well, but isn't that a bit of a stretch of an argument? I mean, we can still discover it. We don't have to be living inside of a black hole for us right now

to understand what it's like to live in a black hole. Yeah, that's right. It's possible that we could in the future discover FTL travel. My point is essentially that there's some limitations to the possible outcomes. You have an infinite number of roles that die, but the die might have some limitations on those possible outcomes based on the configuration of space. Not everything that is possible actually does happen,

only things that are possible and that are potential outcomes from the initial conditions of the universe. Like, for example, having the entire universe collapse into a black hole, physically possible, there's nothing against the laws of physics from that configuration, but you can't get to that configuration from here. There's lots of things between you and that arrangement of stuff in the universe. So not every arrangement that's physically possible will actually be realized by our universe because we start from a certain configuration. But then in an infinite universe, don't you get all infinite possible starting conditions?

Yes, great question. We don't know, right? Because we don't really understand the starting configurations of our universe. We know that we had a fairly smooth universe with some quantum fluctuations. We don't really know exactly where those came from and what came before that. So we don't know if we've like really explored the full range of possible initial configurations or if we're only getting a little slice. Or maybe elsewhere in the universe, they got different initial configurations.

We just don't know. I guess I think James is saying if it is possible for humans, at least, to come up with faster than light travel, then if there are infinite number of humans out there, then they must have surely discovered it. Just because it's maybe more likely for a black hole aliens to discover it doesn't mean that we can't discover it or that it's not possible, right? Because it's the same loss of physics, isn't it? Yeah, that's right. If it's possible for humans to discover FTL travel, then I think you're right in an infinite universe, they will. But there's a difference between is FTL travel allowed by the laws of physics and is it possible for humans to discover it?

Another possibility is the universe allows faster than light travel by some crazy warp technology. But humans are just not smart enough to figure it out. That it's not discoverable by us and any of our infinite brethren because it just requires like much more mental computing power than we're capable of. But that's why we build AI. Yeah, that's a great point. So like machine augmented human intelligence might not have the same kind of limitations. So that's a way around that argument. So, yeah, it's a really interesting, I think quite powerful argument.

There are a few nuances and subtleties there. But I think he's right that we can say a lot about the likelihood of FTL travel from the fact that we haven't been visited. Or maybe you're right. And our corner of earth is just too boring. Infinitely boring. Well, I think the other big limitation is just time. Like maybe you need more time for any of these infinite. civilizations to come up with faster than light travel and maybe the universe is just not old

enough you sort of also need infinite time right you definitely need time but how much time you need depends a little bit on like how fast this faster than light travel is if you can go anywhere in the universe in a moment like with a wormhole then you're really visitable from anywhere in the infinite universe and you know the universe is pretty old 14 billion years is a long time we're sort of late in the era of the universe our solar system's only been around for a few billion years. So in an infinite universe, there will have been civilizations that started billions and billions of years ago and certainly have had time to reach us. Or maybe not, right? Like maybe you need more time, right? And the other thing I was thinking

about is that if it is an infinite universe, that means there are an infinite number of places you can go, which means like the likelihood that some alien civilization with faster than light travel would come to our planet is almost like infinitely small too, isn't it? Yeah, there's a lot of infinities here. You tackle a lot of similar ideas when you think just about the more standard Fermi paradox. Like the galaxy is pretty old and not that big. Why haven't we been visited even without FTL travel? Because it only takes like a few tens of thousands of years to explore the whole galaxy, either with like self-replicating probes or even a small fleet of ships. So I think the same math holds there. That in an infinite universe, you should have an infinite

number of aliens with FTL travel and eventually some of them should reach us. And given how old the universe is, it is a little odd that we haven't been visited. And the other counter argument to James' idea here, I feel like it's like, how do you know we haven't been visited by aliens with faster than light travel? You know, like, how do you know, I'm not a time traveler from the future? Or maybe James is actually an alien, and this is his way to sort of introduce subtly the concept into the zeitgeist. I see.

Maybe he's an alien and a time traveler. But maybe he's an alien from the future. James, if you're visiting alien or visiting human from somewhere else far away in the universe, I hope you don't find us too boring. I hope he finds us only finally boring. All right, well, let's get to more questions from kid listeners. But first, let's take another quick break. A foot washed up a shoe with some bones in it.

They had no idea who it was. Most everything was burned up pretty good from the fire that not a whole lot was salvaged. These are the coldest of cold cases, but everything is about to change. Every case that is a cold case that has DNA right now in a backlog will be identified in our lifetime. A small lab in Texas is cracking the code on DNA. Using new scientific tools, they're finding clues in evidence so tiny you might just miss it. He never thought he was going to get caught, and I just looked at my computer screen. I was just like, ah, gotcha.

On America's Crime Lab, we'll learn about victims and survivors, and you'll meet the team behind the scenes at Othrum, the Houston Lab that takes on the most hopeless cases to finally solve the unsolvable. Listen to America's Crime Lab on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Hey, sis, what if I could promise you you never had to listen to a condescending finance, bro, tell you how to manage your money again. Welcome to Brown Ambition. This is the hard part when you pay.

down those credit cards. If you haven't gotten to the bottom of why you were racking up credit or turning to credit cards, you may just recreate the same problem a year from now. When you do feel like you are bleeding from these high interest rates, I would start shopping for a debt consolidation loan, starting with your local credit union, shopping around online, looking for some online lenders because they tend to have fewer fees and be more affordable. Listen, I am not here to judge. It is so expensive in these streets. I 100% can see How in just a few months, you can have this much credit card debt when it weighs on you. It's really easy to just like stick your head in the sand.

It's nice and dark in the sand. Even if it's scary, it's not going to go away just because you're avoiding it. And in fact, it may get even worse. For more judgment-free money advice, listen to Brown Ambition on the Iheart Radio app, Apple Podcasts, or wherever you get your podcast. Your entire identity has been fabricated. Your beloved brother goes missing without a trace. You discover the depths of your mother's illness. the way it has echoed and reverberated throughout your life, impacting your very legacy.

Hi, I'm Danny Shapiro, and these are just a few of the profound and powerful stories I'll be mining on our 12th season of Family Secrets. With over 37 million downloads, we continue to be moved and inspired by our guests and their courageously told stories. I can't wait to share 10 powerful new episodes with you. stories of tangled up identities, concealed truths, and the way in which family secrets almost always need to be told. I hope you'll join me and my extraordinary guests

for this new season of Family Secrets. Listen to Family Secrets Season 12 on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Hola, it's HoneyGerman, and my podcast, Grasasas Come Again, is back. This season, we're going even deeper into the world of music and entertainment, With raw and honest conversations with some of your favorite Latin artists and celebrities. You didn't have to audition? No, I didn't audition.

I haven't audition in like over 25 years. Oh, wow. That's a real G-talk right there. Oh, yeah. We've got some of the biggest actors, musicians, content creators, and culture shifters sharing their real stories of failure and success. You were destined to be a start. We talk all about what's viral and trending with a little bit of chisement,

a lot of laughs and those amazing Vibras you've come to expect. And of course, we'll explore deeper topics dealing with identity, struggles, and all the issues affecting our Latin community. You feel like you get a little whitewash because you have to do the code switching? I won't say whitewash because at the end of the day, you know, I'm me. But the whole pretending and code, you know, it takes a toll on you.

Listen to the new season of Grasasasas Come Again as part of my Cultura podcast network on the IHartRadio app, Apple Podcast, or wherever you get your podcast. All right, we're answering questions from kids to celebrate the release of my new book, Oliver's Great Big Universe. Let's get to our last questions here from kid listeners. The next one comes from Ida.

Hey, Daniel and George. Would I have special powers if I was inside a black hole? Awesome question. I'm going to say the answer is yes. next question you are the superhero science expert on the podcast yeah what kind of special powers would you get from being inside a black hole oh boy i feel like i could write a whole other book about this idea sounds like you and ida should write that book idas great big black hole done well let's see her question let's bring it down she asked

would she have special powers if she was inside a black hole do you think this is sort of like a bitten by a radioactive spider kind of situation? Or maybe I think she's saying like if she lived inside of a black hole, would life be the same for her or would she be able to do things she couldn't do outside of the black hole? Yeah, I see. Well, there is one way in which being inside a black hole would be pretty different from living on Earth. And that has to do with the flow of time.

Right. We know that time goes slower when space is curved. The same way that space is curved near masses, time is essentially also curved. space and time curved together. What that means is if you're near something really, really massive, your time goes slower. Like somebody far out in space, their time goes faster than somebody standing on Earth. And near a black hole or inside a black hole, time goes super duper slow. How slow? Like to zero? It depends a little on the observer, but if you're far away from a black hole and you see somebody falling into a black hole, you will see their time go slower and

slower so that you'll never actually even see them cross over into the black hole because their time will slow down so much they'll sort of asymptotically approach the black hole from their point of view they will fall in the black hole and they will see your clocks speed up by how much depends on the mass of the black hole that you're falling into i see so the power you get by falling into a black hole is you get to fast forward the rest of the universe yeah you get to fast forward the rest of the universe like if it's infinitely boring you can just be like skip exactly that button that says like skip intro or skip recap you can just like skip everything I just want to see the credits exactly skip forward to see the credits and so you'll see the rest of the universe going in fast forward you'll see like the end of our star you'll see the collision of our galaxy with other galaxies all this kind of stuff will happen now you'll actually see it all through just a tiny little pinprick because if you're actually within an event horizon of a black hole all the light in the universe still comes to you but it comes to you but it comes to you you through this tiny little dot.

Most of space is so bent that everything in front of you is just the singularity. But there'll be this tiny little dot behind you where photons can still make it to you and bring you news of the universe you fast forwarded. Well, first of all, as we talked about before, it is possible to go into a black hole, right? Like if a black hole is big enough, then its event horizon is at a point where you wouldn't necessarily get shredded by the gravitational forces. Like, it is possible for someone like you and me to go into a black hole. Yeah, and as we talked about in our recent book, frequently asked questions about the universe.

As you get closer and closer, the event horizon swells to take up a larger and larger portion of your view. Eventually takes up like half of your view and then it grows around you and then you can only see a tiny little dot. But then you could potentially still be conscious and be thinking about and experiencing this phenomenon, right? Like you'd be like, oh my God, what's going on? Now, Ida's question is, would you have superpowers? I think fast forwarding to the end of the universe feels like a special power. It's not a superpower in the sense that it's not like supernatural. It doesn't break the laws of physics.

But I think what physics can do is pretty special. So I think it counts as a special power, even if it's not a superpower. I guess like if you fell into a black hole and you survive, your body wouldn't necessarily change. So you wouldn't get the superpowers necessarily. But I wonder if maybe Ida's wondering like, you know, like if you go to the moon or moon here, you could jump really high, for example, because there's less grass. Would there be any kind of things I could do in a black hole I couldn't normally do? I think in a black hole you'd never have to worry about cleaning up. You could just throw stuff into the singularity.

You'd basically never have to take out the trash. Yeah, that's a superpower for sure. I'm not sure that they'll let you into any Avengers team or anything like that. But you know, you said earlier that it is possible maybe for there to be planets inside of a black hole, you know, orbiting a star and stuff. Would life be different for them or would it be the same as it is? is for us. Life would certainly be different for them.

And you could check out our podcast episode. I think Katie was our co-host on that one because they would see things very differently, right? You wouldn't have any illumination. And your planet would be really hot on the inside, it would be squeezed by the tidal forces. It would be more like living on the moon of Jupiter, you know, like Io, which is very volcanic. So it would be a very different kind of experience. Kids on that planet wouldn't look up at the night sky and see the same things that we see.

They would see a completely black night sky except for a tiny little dot through which which they would see everything else in the universe. Could they see like the hand in front of them? Like if I put my hand in front of me inside a black hole, could I see my hand? On the outskirts of a super massive black hole, space is not so occurred that you couldn't see anything. And so it is possible for light to still make some progress towards your eyeballs and the outskirts of a super massive black hole. Like you'd be inside, but you'd be near the edge.

So maybe you could, you would see your hand, but it would all be kind of weird and distorted. All of space would be very distorted. The way time would flow would be different. People closer to the center of black hole would have their clock slow down compared to people further from the center of the black hole. So it would be pretty hard, for example, to have like a Zoom session across the whole planet if you're living inside a black hole. Oh, thank goodness. Great. There's your superpower.

You can say no to all online meetings. That's right. It'd be infinitely boring. Just like a regular Zoom meeting. All right. Well, to answer IRIS question, it sounds like she wouldn't gain any special. special powers, except the ability to see the rest of the universe in fast forward. And to never have to clean your room.

Although I think if Ida ever makes it inside of a black hole and lives to tell about it, I think she would be a superhero in my book. All right. Our last question comes from Joey. What are the newest and the oldest black holes in the universe? What are the newest and oldest black holes in the universe? Awesome question. A little nosy if you ask me.

You don't think he deserves to know. I'm saying if you go around asking people's age, you know, you might get some current answers. I see. No, I think the biggest, oldest black holes in the universe are probably proud of their status, you know? They're like silverbacks tromping around in the jungles at the hearts of galaxies. I see. Yeah, they're like the alpha black holes. Is that what we're saying?

Yeah, the OGs, exactly. All right. Well, this is an interesting question because we know that black holes form very, very early on in the universe and we know that black holes are forming all the time right now. So, you know, I wonder if his question is, what are the oldest and newest black holes we know about or what are the oldest and newest black holes that exist in the universe? Yeah, right. Both of those are good questions. In the case of the oldest black hole, we definitely don't know what is the oldest black hole or theoretically what could be the oldest

black hole because there's one theory that black holes are as old as the universe itself, that they might even like be older than electrons, that black holes could have been formed during the Big Bang. Whoa, wait, even before we had, like, quantum field. Before we had matter, before those quantum fields settled down so that we could have things called electrons and protons and quarks, when things were still so hot and so dense, that talking about them in terms of those objects

doesn't make a lot of sense, the way you wouldn't talk about a wave in terms of its drops. So there's this theory of primordial black holes that suggest that very hot patches of the universe, might have collapsed into black holes even before matter was formed and those black holes might still be around. They wouldn't have evaporated by now or right? Because black holes don't die very easily. Some of the black holes would definitely have evaporated. The bigger black holes evaporate more slowly and smaller black holes evaporate quickly. So we would expect that some of them to have

evaporated and some of them to still be around and some of them to be evaporating right now. So if this scenario is true, we should be able to see these primordial black holes like evaporating all the time. So maybe the oldest black hole in the universe was there from the beginning, from the beginning of the universe. It's possible. It's even this fun theory that this impact in Siberia about 100 years ago, which mysteriously left no crater, was actually a primordial black hole that took like a core sample of the earth instead of an actual meteor. Whoa. Well, we should do an episode about that. We should. The problem with primordial black holes is, again, if they were created, we should

see them evaporating all the time and we haven't ever seen one we've looked for evidence of black holes evaporating very bright flashes of hawking radiation but haven't seen any so it's a possibility that there are black holes as old as the universe but it's still just theoretical but we have seen some very very old black holes like actually seen them so then what's the oldest black hole we know about the oldest black hole we've ever seen was formed around 500 million years after the big bang it was seen by the james web space telescope it's super duper far away, which is why we can see so far back in time. Remember, light takes time to get here. And so the further things are, the further we're looking back in time. So we're seeing

this black hole, which formed just a few hundred million years after the Big Bang. It's called Sears C-E-E-R-S-1019. Well, what that means is it, it's like 13, 14 billion years old? That's exactly right. It's between 13 and 14 billion years old, which is pretty old. At the time, the light left it, you only had about 9 million solar masses, which is much smaller than some other supermassive black holes, which have grown to like billions of solar masses. In the meantime, of course, it might have grown. The light we're seeing is very out of date. Or it might have disappeared, right?

We don't actually know it's the oldest black hole. We just know that it was around a long time ago, but by now it could have maybe disappeared or evaporated. Isn't that possible? It's possible. You're right that we're not getting new information about this very quickly. We'd have to wait billions of years for the updates. But it's unlikely that a massive black hole in a cluster of stars, which is where we've seen it, would evaporate into nothing.

To evaporate, it really has to be isolated to not be fed at all. And a black hole with 9 million solar masses is going to have very, very faint hawking radiation. The hawking radiation goes like inversely proportional to the mass. So very low mass black holes evaporate more quickly than very high mass black holes. What if Ida went into that one and broke it up? That would be a superpower. Yeah, maybe she did get superpowers when she went in. All right, so that's the oldest black hole we know about.

What are the youngest black holes we know about? The youngest black hole in the universe is certainly one that was created right now. And then another one created right now. I mean, they're happening all of the time. We know that supernovas, which are typical precursors for black holes, happen like every 50 years in our galaxy. But, you know, there's trillions of galaxies out there. So there's almost certainly a black hole being formed as we speak.

And by the time you listen to this podcast, that will be out of date. It'll be a new black hole formed that's even more recent. So the youngest black hole in the universe is definitely one that was just formed. They're probably forming all the time right now, right? Especially if it's an infinite universe, there's an infinite number of black holes being born right now. Yeah, that's exactly right. So the youngest black hole is constantly being replaced by some new baby black hole. But what about the youngest one we know about?

So the youngest black hole that we have seen is called W49B. It's about 26,000 light years away from Earth, and we know it's about 27,000 years old, because the light from it indicates that what we're seeing is a black hole that's about 1,000 years old. So we're looking at the remnants of a supernova collapse that formed a black hole about 27,000 years ago, 26,000 light years away. So to us, it looks 1,000 years old. But wait, wait, wait, how do we know its age? We can tell it's age from the light we get from it, or we just saw the supernova and assumed that a black hole formed inside of it? Yeah, great question. This one we can actually deduce the history of it just by running the clock backwards.

We look at the distribution of iron and sulfur and silicon in the remnant, and we can tell what happened and how long it's been drifting. So we can run our clock backwards essentially and say, oh, this is about a thousand years old. The same way you could look at a mushroom cloud from a nuclear bomb, you could tell when it went off. And you can actually see the black hole in the middle? But I thought we could only see black holes if there was like a quasar or something. Yeah, you're right. We can't see the black hole directly because the black hole is black. We're deducing the presence of the black hole from the mass of the whole system and the x-rays from the hot gas that are nearby. And so according to our model, a black hole has formed.

Like what we're seeing is consistent with a star that exploded and left behind a black hole. All right. So then the youngest black hole that we think we know about is about a thousand years old. It looks a thousand years old to us, but it happened 27,000 years ago. I mean, we caught it, like we took a picture of it when it was 1,000 years old, but the picture was taken 26,000 years ago. Exactly. And to answer your other question, like, it's possible that we did see this thing go supernova that like Chinese astronomers a thousand years ago were looking up in the sky and saw it. We do have some examples of that where we see a supernova remnant and we can find in the historical record Chinese or Persian or Indian astronomers writing about that supernova, which is pretty cool. Not in this case. but it's possible the humans did see this one blow up a thousand years ago.

Whoa. Do you think kids asked questions about it back then? It's been a great big universe for a great long time. So yeah, probably. All right. Well, I think that answers Joey's question. The oldest black holes in the universe might be the ones that were formed with the universe, but we don't know for sure.

There is one that's at least 13 to 14 billion years old that we know about. And there's one that was born about 27,000 years ago. that is the youngest one we know about, although there are probably definitely black holes being born all the time right now. And I hope that one of those black holes is being formed near some distant human civilization that's inspiring them to invent faster than light travel.

And maybe better cleaning technology because we could all use that. And maybe give Ida special powers so that our corner of the universe becomes less boring and we get more visitors. I think if you take all of these kits and put them into a team together, they'd be like a superhero physics team.

I mean, these kids are so, curious and clever and smart. Yeah, well, I hope that they and all the kids inspired by your book do solve some of our problems and change the way we understand the universe. So thanks again to all of our kid question askers and to all of our listeners for sending in their questions. That's right. What's that website one more time? Great big universe.net. We hope you enjoyed that. Thanks for joining us. See you next time. Thanks for listening and remember that Daniel and Jorge Explain the Universe is a production of IHeartRadio. For more podcasts from IHeartRadio, visit the IHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.

I'm Mani. I'm Noah. This is Devin. And we're best friends and journalists with a new podcast called No Such Thing, where we get to the bottom of questions like that. Why are you screaming? I can't expect what to do. Now, if the rule was the same, go off on me.

I deserve it. You know, lock him up. Listen to No Such Thing on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. No Such Thing. I'm Dr. Joy Hardin Bradford, host of the Therapy for Black Girls Podcast. I know how overwhelming it can feel if flying makes you anxious.

In session 418 of the Therapy for Black Girls podcast, Dr. Angela Neal-Barnett and I discuss flight anxiety. What is not a norm is to allow it to prevent you from doing the things that you want to do, the things that you were meant to do. Listen to Therapy for Black Girls on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. Let's start with a quick puzzle. The answer is, can see? Jennings' appearance on The Puzzler with A.J. Jacobs. The question is, what is the most entertaining listening experience in podcast land? Jeopardy-truthers believe in...

I guess they would be conspiracy theorists. That's right. They gave you the answers, and you still blew it. The Puzzler. Listen on the I-Heart radio app, Apple Podcasts, or wherever you get your podcasts. This is an I-Heart podcast. Thank you.