Daniel and Jorge answer questions about the Universe from Jorge's daughter Elinor, and talk about their new PBS Kids TV show: "Elinor Wonders Why". Link: pbskids.org/elinor
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Hey, Daniel, do you think humans will eventually discover all of the deep secrets of the universe?
M I guess I think it depends on what you know. It depends on how curious future generations are. If the kids growing up today are curious enough, who knows what they might discover.
Well, that's why I give my kids plenty of vitamin.
C so they'll have a strong immune system to survive the next pandemic.
Actually, I mean see for curiosity, so they're not immune to amazing discoverage.
As long as they don't get a see in science.
But see for catching it all right, that's right. I am Moorhee. I'm a cartoonist and the creator of PhD comments.
Hi.
I'm Daniel. I'm a particle physicist, and I'm super curious about what our kids will discover.
Welcome to our podcast, Daniel and Jorge Explain the Universe, a production of iHeart Radio.
In which we ride that curiosity wave. We take the power of your curiosity, and we take it all the way to the end of the universe and look backwards. We try to understand the very big the very small. We ask all the questions, from the littlest ones to the biggest ones, to the hardest ones to the weirdest ones.
Yeah, because it seems to be part of human nature to ask questions, you know, to ask questions about their surroundings and even about the universe. It seems like we're all curious at some basic level.
That's right. And sometimes we want to know the way things work around us for practical reasons like wow, how fast can that leopard? Am I faster than it? And sometimes we just want to know. We want to understand the context of our lives. How should we live, what does it mean? Where do we all come from. It's a deep seated need to understand the universe around us, and it's translated into a pretty impressive set of knowledge about the universe and how it works. But it's also shown us how much we still have to understand.
Yeah, and it's not just scientists who have curiosity. It's kind of everyday people, right.
It's everybody. When I talk to people about what I do for my job. Their eyes light up. Well, first they say physics, man, I did terrible at physics in high school. And then they go, oh, wait a second, I want to note the answer to that question, what is the universe made out of? Or where did it come from? Everybody's curious, and on this show we believe that wondering and curiosity belongs to everybody.
Nobody ever confuses you for a psychic instead of a physics person.
That's never happened, not even once. They can read my mind, so they can tell that I can't read theirs.
Well. Today we have a very special episode because we are announcing the release of our television show. I don't know how many of you out there follow us on social media on our Instagram and Twitter, but Daniel and I have made a television show for kids.
That's right. It's the next step in our adventure of collaboration. We started with online videos and then wrote a book together, and we've been doing this podcast and the next step is this TV show which celebrates and supports curiosity, especially scientific curiosity in children.
Yeah's a show called Eleanor Wonders Why, and it premieres this week on ppskids dot org. And on the PBS Kids app, and also on the Pskids YouTube channel, and also on Amazon Prime if we have the PBS Kids subscription.
It will dig into the details of what that show is about. But basically, it's about a bunch of curious kids asking questions about the world they find themselves in and figuring out the answers for themselves.
Yeah, it's a project that Daniel and I are super excited about. We've been working on it for years, kind of on the background of this podcast. We're super excited to share with you and with all of the kids in your lives, whether there are nieces and nephews or grandkids or kids.
So, if you're a fan of science and you're a curious person and you'd like your kids or your friends kids to grow up with a scientific mindset and explore the universe and answer some of these deep questions that we all have about the universe, maybe give it a try.
Yeah, share it with them. And So the show is called Eleanor Wonders Why, and it's based sort of on our kids, but specifically the main character is called Eleanor and she's the bunny rabbit in this world of the show. But she's based a little bit on my daughter Eleanor, and so today to celebrate the release of the show, we thought it'd be cool to answer some questions that Eleanor has about the universe.
That's right. We were hoping in this show to model the way that we talk to our kids about science. We answer their questions, we reflect their questions back to them, but also to tap into that curiosity that kids have in its raw form. Those of you who have curious kids, and I know many of you have written into the show and sent in their questions, know that their questions are wonderful because they asked the deepest but most basic questions about the universe around us.
Yeah, and it sort of seems like once they get into school, a lot of that curiosity gets sort of ground away or beaten down a little bit, doesn't it.
I don't want to say anything negative about school teachers, because they're having a hard time these days, but it's true that that joyful curiosity, that wondering about the universe, there isn't always a place for that in your normal, everyday school curriculum. And so we were hoping this TV show would help supplement that, would help inject that wonder and that excitement about the very biggest questions and also just the world around you.
Yeah, and so we have two questions here today from the real Eleanor. And these are questions that she totally just came up out of normal conversation, like we were just folding laundry and suddenly she had these. She gave me these two big questions about the universe.
Always just like popping questions about the universe on you at all times.
Oh yes, did I mention she inspired a show called Eleanor Wonders. Why.
Those of you with curious children will know what that's like. So we're happy to answer Eleanor's questions today, and we hope that you and or your kids have similar questions.
Yeah, and if your kid has questions about the universe, about planets, about Adams, or anything related to science, please send them to us. We'd be happy to try to answer them and maybe even possibly answering them on the podcast.
That's right, We answer all of our listener questions, So write to us with your questions. Two questions at Daniel and Jorge dot com.
All right, Eleanor has two questions about nothing short of the entire universe, Daniel, she has big thoughts. She's a little seven year old girl, but somehow she had these questions about the universe. And honestly, as a parent, I don't know where they where they came from, Like I don't know what books she's reading, what videos are showing to her at school, But she had these amazing questions the universe.
Clearly, you have interacted with physicists too much, or she's thinking about.
This maybe probably is there such a thing as too much interaction with the.
Obviously? I think not. All right, here's Eleanor's first question.
Yeah, so Ellen has two questions, one about the multiverse and the other one about the shape of space.
How can I universe? How can there be more than one universe? If the universe is probably infinite because I thought the universe was everything that existed.
Whoa, that's a big question though, such a small brain, such a big question. I don't even know how she knows about the multiverse, Like we don't talk about it over dinner.
Yeah.
Well, and she has the idea of the infinite universe, which is hard enough for me to hold in my head. What do you think she thinks of when she talks about infinity.
Well, that's a big question. I think I think she has an understanding of like things that go on forever, like they don't stop. You know. Definitely they used infinity a lot, like you know, when they're when she's arguing with her brother or something. You know, I want infinity of these?
Or how many cookies do you want for desert? Infinity?
Infinity? Yet, it's definitely a concept she's familiar with. But what do you think about her question? I think she's asking, you know, how can there be more than one universe if the universe might be infinite? Like how like where are they? I think maybe she's sort of asking, like where are these other universes if the universe is infinite?
Yeah?
Or do you think she's gonna be just asking it like a semantics question like why why can you have a universe and a multiverse? Wouldn't it all just be the universe? Yeah?
Well, I think the answer there's a scientific answer and a semantic answer there because you know, originally, I think universe is designed to mean everything that there is. It's just like, instead of saying the phrase all the stuff in all the space and all the matter and everything, you want a more compact phrase, and so we have universe. But then that sort of came to define a set of ideas, and when you want to expand on those ideas, then you need to add a new word for a new meaning. So like if universe is sort of semantically flexible, it means like our current understanding of everything that could possibly be, then yeah, there's just one universe by definition.
In case you sort of downgraded the definition of universe, like it used to mean everything. But then yeah, physicists where like maybe there's more to everything, or where there's more everything everywhere.
Else and specifically we had new ideas for how to get more everything or where more everything could be, or in other ways you could have stuff, and so there's sort of categorically different kinds of stuff and places and so that I think is why we came up with a new word for it. But maybe we should talk a little bit about what it means to have more than one universe or where that other stuff could be.
Yeah, yeah, because I think what sort of blowing her mind is just this idea that there's everything and then there's other Everything's like where are they? Are they next to the other everything, or are they on top or how does that work?
Yeah, And it's especially hard to understand if the universe is infinite, because then how do you squeeze all that stuff together? Right? And when people talk about universe, they often mean different things, and so sometimes it's just semantics. And sometimes when people say the universe, they really mean the observable universe, like the part of the universe that we can see, which goes out several billions and billions of light years, right. And sometimes people think of other universes as just like other observable universes. If you're somewhere really really far away, you would have a different observable universe because you would see a different like patch of the infinite universe. I think that's kind of lame, because we already have a phrase for that observable universe.
It's like a subuniverse.
Yeah, exactly. It makes our observable universes like a sub universe of the whole universe. So technically that's in the category of multiverse. Some people call it multiverse, but I think it's sort of silly. I think more interesting is this concept like that our universe could be infinite and yet there could also be other universes.
Right, yeah, because like how do you fit it all in?
How do you fit it all in exactly? And to fit it all in you have to have like other kinds of space because remember that what we think about is our universe is the space we live in, the space and all the matter and all that stuff, and that could go on forever, right, But then also there could be variations on it. And really the only way to reconcile having an infinite universe and having multi universes is to go for the quantum multiverse, the one where our universe is splitting into different possibilities at every moment.
So this is the idea that every time, like a particle makes a decision, another universe pops out.
Yeah, exactly. It's to try to answer the question like when the universe makes a seemingly random decision for quantum mechanics, why is it that one and not another one? When the electron has to decide do I go left or do I go right? Then you know, why is it go left? It seems weird, It seems arbitrary, and as you know, physicists don't like things that seem arbitrary. We want an.
Explanation kind of like children, right, they always want to know why why can't I have cookies at nine pm at night?
That's what's going on. The show is really called physicists wonder why why died? To make a kid's show? It seems arbitrary. Then it seems arbitrary, So we invent this other universe to say, well, maybe it's balanced. You know, we're in the left direction, but there's another universe where the electron went to the right direction, and that somehow satisfies your need for symmetry, for balance, to say that it's not just arbitrary that it went left, because it went in every direction and we just ended up in one of those right.
And the idea is that there weren't two universes before, but once that particle makes a decision whether it's spinning right or it's spinning left, then now there are two universes. So before there was one, now there are two. And that happens every time a particle in all of existence makes a decision.
Yeah, and it's crazy, right, it's hard to imagine because there's ten to the eighty particles and they're doing stuff every you know, nanosecond or whatever, and so the number of universes just becomes absurd, very very quickly. Plus the universe is billions of years old, so like, how do you even fathom the number of different universes in this scenario? It's like infinity to the infinity to the head explosion power. You know, it's just it's just the number. We can't even really think about. It's more cookies than even your kids could eat. Yeah, even at nine pm, even at nine pm. Although they'll happily take the challenge, I'm sure you got to take data, right. You can't just make assumptions. You got to do the experiment.
Can post limits.
Doesn't really answer her question right, like say that that's true, say that that's actually happening, that that's our reality. Then where are those other universes? You know, where are they in space?
Right?
And that's not easy to answer. They're not really like anywhere you know, have branched. We are in the left universe and not in the right universe. It's not like the right universe is one we can ever interact with. We can't like send a message to that universe. We're not causally connected. We're separated from that universe, so we can never interact with it in any way. It can't influence us. We can't send messages, it can't change us. So from our point of view, it doesn't exist in our space at all.
Well, how do you know that, Daniel? I guess how do you know that there's no way that we can make a connection to them? Because in science fiction you see it all the time, like breaking the walls between the different universes and you can travel to a different universe?
Are you saying I saw this in a movie? So how do you know it's not possible?
Basically, I also saw flying saucers and jetpack Daniel, So we'll get to those labor.
Well, it comes from the very construction of the multiverse, right, the multiverse. The other universe is created when the universe splits when you make a different decision. So then our universe is inconsistent with universe. It's like a copy of our universe, but with a different decision. So the two have like the same history, but now a different future. And so how did the two even talk to each other? They have like an inconsistent history for what has happened. It's like an alternative. It's not like you know, a different fork in the path. Well, I'll go left and you'll go right, and maybe the paths will meet again. It's like you know, once you decide to press the button, you can't unpress the button.
All right, I think now I have a lot of questions about this, Daniel, and so let's get into where these other universes might be. But first let's take a quick break.
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All right, today we're answering questions from Eleanor, my daughter, who was also the inspiration for our new kids television show called Eleanor Wonders Why, which is all about getting kids interested and curious about nature and all the amazing things in it, like animals and bugs and lizards.
Maybe mosquitoes actually came over from the multiverse because I hate them so much, but I love nature.
You think they come from a dark, dark universe.
I imagine, like, who would suffer if we just deleted mosquitoes from the universe? Really nobody would be harm Can we just all vote to do that?
In lie I think bats eat mosquitoes, Daniels, so that would be bad news for bad which, by the way, is also a co in our show. So Eleanor in the show is a bunny rabbit and she has two best friends, Ari, a funny and very active bad and also all of who's an elephant, and all of it is sort of based on your daughter, right, Daniel.
All it is partially inspired by my daughter. That's right. All of the character in the show is a real reader and likes words, and my daughter Hazel is like that. Yeah, so she helped inspire us. And the curiosity of all of our children and of all the children we've met out there helped inspire us. I give sometimes lectures to elementary schools about science, and my favorite bit is the question period afterwards, when they ask any question they have in their mind, and they're always like surprising and mind blowing, and sometimes it's difficult to answer questions.
Yeah, so if you have young kids, or if you have friends with young kids or nieces or nephews or grandkids, we would really encourage you to tell them about the show. It's called Eleanor Wonders Why, and it's available right now in the US at Pbskids dot org, slash Eleanor E l I n O R and also the PBS Kids app, which you can download for free and watch all these episodes for free. They're also available on the TBS Kids YouTube channel and also on the Amazon Prime TBS Kids subscription those who can put on repeat, which we hear a lot of parents are appreciative of. So today to celebrate that, we are answering questions from Eleanor, the real Eleanor. And she had a question about the multiverse. So, Daniel, we were talking about the multiverse. If the multiverse is real, where where are all these other universes at? So you're saying we can't access them, we're not connected to them, because it's more like we're different possibilities. Is that kind of one? What do you mean? Sounds very abstract, like are you saying We're an abstraction in.
That theory of the multiverse, where there's different universe created every time a quantum mechanical particle has to the roll of dice. Then yes, we are just one of those many many, many, many many many many to the many power universes, and so to people in or creatures in one of those other multiverses, we are that abstraction. And that's the part of this theory that I don't really like because it tries to answer this question of why are we in this universe and not in another universe where other random decisions were made. Doesn't like randomness, and truest to answer that by saying every random decision is made. But to me, it doesn't really answer it, because you know, I'm in this universe and not in any other one, and so it's it goes back again to that question of consciousness, like why am I experiencing this universe and not those universes? So to me philosophically, it's pretty unsatisfying. Plus it's just hard to think about, like where are all those other universes? Eleanor's question is a great one, you know, how do you have multiple infinite universes where are they? Yeah, And you know, the best way to think about it is that we have an infinite pocket of space to play in here, our universe, our quantum slice of the universe, and those other ones they have their own infinite pockets of space to play with, but they're not connected to hours. The only way to answer the question where is something is to think about their physical relationships, you know, like where is your neighbor's house. It's next to yours.
Because our brains are sort of hardwired to think about space like that, right, like spatially.
Well, that's what space is. Remember, there's no absolute locations anywhere. It's all relative, and so if there is no relative position between this universe and the other universe, then you can't put them in any space together. So they really have their own spaces.
So I think what you're saying is that I should tell eleanor that Daniel doesn't know.
Daniel definitely doesn't know if those universes exist and if they do, where they are. But I'm pretty sure that if they exist, we can never talk to them or interact with them, or even prove that they exist. And a lot of people say that makes this not a very scientific idea because if you can't test it, how could you prove it's true. And if you can't prove it's true, then it's really just speculation and not even really.
Science, right. Yeah, you need to be able to formulate it right, like as a hypothesis, and be able to prove it or disprove it, or design a test to prove it or disprove it.
Yeah.
A lot of people like Carl Popper's theory of falsifiability. That is an idea is not scientific if it's not falsifiable, And then some people think that's garbage. But I just feel like, how are you going to pick an idea? Like, sure, you have this idea of quantumultiverse, somebody else has another idea. If you have competing ideas, to me, the way to pick between them is to do the experiment. That's what experimental science is about, as a way of cornering nature into revealing what's happening by constructing a situation where different things happen based on the reality. You know, the experiment, the particle goes left if it's this way, or it goes right if it's that way, and that way the universe gives you a clue. But if there's no way to interact with the rest of the multiverse, there's no way to prove it's there, then is it really there? And if it is, does it really matter?
All right? Well, it sounds like the answer is we don't know, but we may never get to these other universes. And also maybe the answer is a little bit like, don't think about it as these other universes being anywhere like on top of us or next to us or below us, but think about it more like there's just sort of like there as well as us, right, Like it's just there. They're just there, just like we are here.
But even the word there implies a space. You're like, they're over there. Well I would say they are where they are and we are we are? Yeah, I would stop it are not they are there? Just they are we are? They are? Where are there? We don't know?
All right? Well, awesome question. We also have another question from eleanor here if we're going to try to answer, and it's about the shape of space. Does a year I have a shape?
And is it like a giant wall that is like curved and you can't come out of it?
All right? Awesome questions She's asking about what the shape of space is, and if it has the shape, what's at the edges of it? Like, if it has a shape, it must have an end, and so what's at the end. Is it a curved wall, is it a flat wall? Is it a stuccle wall? Who knows?
I think she's been stuck inside too long. She's thinking about edges and boundaries.
Oh boy, you know. And now that I think about it, I do kind of see the inklings of these questions where these questions sort of came from. Like I'm thinking back over like the last couple of months or years, I've seen her sort of formulate this question a little by little, Like she asked a little bit about the universe, a little bit about space, a little bit about this, and I think it all just been sort of marinating inside of her head.
Well, it's awesome. As kids grow up, they understand more and more about the world around them, and then there's sort of mental context grows. They can imagine the city, other cities, the country, the whole world, the solar system, and then eventually, you know, inside their minds, they're creating this model of the whole universe. And that's when this awesome thing happens that they have questions about it. They're like, wait a second, this model in my head doesn't really make sense or what do I put here? And that's where these questions come from. And that's you know, that's science and action.
Right, And it's pretty cool that she just blurreted out this question, Like we're just folding laundry and she just suddenly pops out this question like it's been building up inside of her and she just had to let it out, Like isn't that cool that I feel like as adults, which is a lot of us, just keep it to ourselves. Like if you were a dinner with a date, you wouldn't be like, you know, talk about one thing and then suddenly be like, hey, have you ever thought about the shape of the universe? But then again, maybe I'm not a physicist, so you've done that.
Then it depends on the kind of person you want to date, that's for sure, But it also depends on the kind of person you are. If you encourage these kind of questions and your children, if you enjoy exploring them with your kids, if having kids helps you renew this like naive curiosity, which still is driving basic questions in science. So I think it's wonderful to tap into. And you know, that's what we try to tap into for our show. A lot of the episodes for our show come from real questions asked by real kids about their universe.
Yeah, and every episode in our show, Eleanor wonders why. We try to think about a question that kids would have and we try to answer it, like why do birds have feathers? And why do lizards like to sit out in the sun? And all kinds of fun kids questions.
And why does my dad not know the answer to my physics questions? Why did he have to ask his friend?
Why does he have to ask you know, one hundreds of thousands of people out on the internet.
Well, let's try to give Eleanor an answer.
Yeah, so she's asking what is the shape of space? Like the space does the universe have a shape? Like if you keep going long enough, what happens? Do you run into a wall? And what does that wall look like? Is it like a physical barrier? Is it curved? Does he have texture? Does it hurt if you slam into it? What's going on?
Well, it's fascinating that she asked this question. Just after she asked the other question where she's assuming an infinite universe. Now she's wondering like, could the universe not be infinite? Right? How do you understand anything other than infinity for a universe?
Right? Well, this one was kind of a follow up question, Like she asked the first question and then she sort of thought about it for a second, and then she has this one. So I think maybe she's also grappling with this idea of infinity. Like you said, like infinite doesn't make sense to her, there has to be an end to it.
Actually, I think the opposite. I think infinity is much more natural than an edge, right, Like, as weird as infinity is, it's hard to grapple with, but it seems sort of natural because then you get to avoid edges. And then we don't have to explain the edge or the weird shape of the universe because it just goes on forever.
But then you have to explain forever, Daniel, And see how this helps you.
Well, I have a very long answer for why forever makes sense. It goes on forever.
It just goes on and on.
This bit on and then there's that bit on and this other bit on, and then yeah, this is the longest podcast ever.
But usually fall asleep before they ask you for a follow up.
And so to answer her question, like, one possibility, one very real possibility is that the universe is infinite, that space is infinite, and that it's always been infinite. The thing that's hardest for people often to understand about the universe being infinite is that they imagine the Big Bang having started the universe from a point, so then how it's stuff get that far away? But instead, all you have to do is imagine not just that our universe is currently infinite, but that it always has been infinite. That the Big Bang was just a period where the universe was denser and hotter, and since then it's been expanding and becoming more dilute. But it went from an infinite hot universe to an infinite cold universe. So that's one very real possibility and that's my sort of personal philosophical preference for which I have no evidence.
That's the Daniel interpretation of total guessing about the universe.
That's right, Total guessing is step one in science though, right, all.
Right, So that's one possibly. But I think she's asking like what if instead of having an infinite universe. We have a finite universe. Yeah, And so if it's finite, what's the shape of it? Like, is it a big feel? Is it in the shape of a duck? Is in the shape of a giant squirrel? Is it a cube? You know? And also like what at the end, Like, if you keep going in one direction of the universe, what happens when you hit the end of it? Do you stop existing? Do you bounce back? What happens?
Well, the basic idea to get in your head before we get into the details is that space is not as simple as you thought it was. Space is not just a place for matter to be like an emptiness you know, on which stuff happens. Space itself can have shapes. And this is something we already know because we see that space bends.
Right.
Our understanding of gravity now is not a force between objects, but the interaction of matter with space. Matter bends space, and then space changes how matter moves. What that means is that space can have a weird shape, right, doesn't just have to go on forever. It can curb, it can bend. It has weird pockets in it, These things space traps, which most of the rest of the community calls black holes are weird pockets of space where space sort of has like a discontinuity.
Edge and like a loop, right, Like in a black hole, you can't you can't leave it because it's it's pulling on you. You can't it's it's a you can't leave it because space around a black hole is like looped right, like it's a doughnut kind of like a circle.
Yeah, space is one directional inside and black hole. So space can do all sorts of really weird things. So first get your sort of like mental idea space be a little bit you know, squishy and flexible and so it can fold and do weird stuff. And then we can insert into your mind other ideas for the shape of the universe and sort of the simplest is that the universe is finite, but it has no edge because it's sort of constructed in a loop. Like if you just keep going in one direction, eventually you'll come back to where you were.
Right kind of like a satellite and orbit around the Earth, or even if you just travel on the Earth in one direction, you'll come back to the same spot.
Yeah, if you build a road around the equator and you just keep driving on it, you'll come back to where you started. And that's because of the geometry of the Earth. Right on the surface of a sphere, you can just keep going, you'll come back to where you are. And you want to real, well, how do you do that for three dimensions? Well, if space is complicated, if space is a thing which can bend and twist and be connected in weird ways, right like around a black hole, then it can be connected in this way so that one bit of space is now connected to another bit of space on what would be the other side of the universe. You can arrange space in sort of a three dimensional equivalent of the surface of a sphere.
Like you can take a universe and kind of wrap it around and connect it to itself. Yeah, and then so you would have a shape. Yeah.
And then the key thing to avoid is trying to understand this by putting the universe into a higher dimension. Don't think about the three D universe on some four dimensional sphere, because that would create another dimension of space, which we don't have any evidence to believe exists. Just think about the relative connections between between things in space. If this point in space is connected to the next point in space, its connected to the next point in space. And then just imagine a ring of these points. Each one is connected to one to the left and one to the right, and together they construct a ring. And then imagine the three D analog of that ring. Again, it's not like on the surface of a three D sphere. It's just about the ordering of the points relative to each other.
All right, Well, let's I have questions about that also, Daniel, and let's get into maybe a little bit more of the specifics and also maybe think about the alternative that maybe if space is flat, what are the possibilities there? So let's do that. But first, let's take a quick quick.
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All right, we're answering questions from Eleanor, my daughter, who is the inspiration for one of the characters in the show Eleanor Wonders Why, which is our new kids show and that is out right now and we're celebrating its release this week. And so Eleanor had a question about the shape of space, and Danny, you were saying that maybe space is bendable, and well, it is bendable, but maybe the shape of space is that it loops around onto itself, like it's wrapped around itself.
Yeah, And that's more like the topology of space than the shape of it. It's like about how the points are connected to each other rather than like, you know, how it's bent by mass in any sort of local configuration. It's sort of like, you know, how you put the whole thing together, and that I think is sort of the easiest one to understand because it lets you have finite space, like it doesn't go on forever without having any sort of edges. Because people feel weird about the edge, like you know, you can't imagine like coming to a brick wall with a sign on it and it says like the universe ends here, because then you wonder like, well, what's on the other side of the brick?
Right?
Yeah, well, yeah, I think you know that's a little bit of where her mind is coming from in that you know, she's probably not aware of these ideas about bending of space. So to her, space is just sort of like this infinite emptiness. And so is that a possibility? Could it be that maybe space is not curved, but it us have an edge, right, because I think we know that space is not generally curve. We think it's flat.
Our local part of space at least is flat, and we think there's enough stuff in the universe to make space generally flat. But yeah, space could be flat, and it could be finite, and it could have an edge. We don't like the idea of an edge because it's a discontinuity. We'd have to explain it. What would it be like, but it's not impossible, right, Space can do really weird things and have edges, Like you know, the event horizon of a black hole is basically like a boundary of space, and so you could come to some boundary and you know, it wouldn't be some like weird thing with like flashing lights and blue stripes or whatever, as they would put it in a movie. It would just be like, you know, space does something weird here, So like there just isn't any more space to go into, like you know, the way in a black hole, you can't just move in any direction you want because space has a single direction you can go in. It could be you come to a point space where there just is no more space in that direction. It's like coming to the north pole. There is no more northiness to go to.
So that is a possibility, is that space could be kind of a flat in its curvings, meaning has kind of a volume, and then it does have an edge to it, like it does end like a blob.
It's a possibility, it's not a frequently discussed possibility or a popular possibility among like current cosmologists. There's no reason for space to have an edge, and so it's not something you need to add to your theory. It's much more natural to just say every point in space is the same, and therefore the universe should be infinite. But it's not against the laws of physics as far as I'm aware, and you know, we imagine the universe having an origin in time. There was a moment in time when things were created and then inflation, dot dot dot dot, and so it's not that outlandish to imagine a discontinuity or an edge also in space.
And then her question was sort of like, what's the shape of it? Like, if it is like this and it does have borders, do you think it'd be like a sphere, like a potato?
Like I think it'd be like a huge question mark.
A question mark. What would be in the dot? Are we the dot?
Daniel, We're in the dot, We're the dot. That's right, that's my philosophy. No, we have no idea. We have no idea if space as an edge, and if it had an edged, what that shape would be. I mean, your intuition would say it should be a sphere, because that's the simplest thing. Yeah, right, But we were just really we just really don't know How awesome would that be though, to discover the universe had an edge and to map it out and to understand it. You know, if it's not a sphere, then probably it would be like a randomly shaped blob controlled by some like early quantum fluctuations or something crazy.
Yeah, I'm gonna go with banana. I bet it's shaped like a banana, and then I'll be justified in all these discussions about bananas.
Daniel, because you knew it the whole time was just a random guess that was later proven out to be true.
You kneed because the universe was speaking to me. It was crying out for, you know, some sort of recognition of it's been in any.
Yeah, and you know, there is another sense in which the universe kind of does have an edge, and that's again just back to like our observable universe. There's only a portion of the universe that we can see. And so if you think about the universe as like the stuff that we can see everything that's around us, that really does have an edge, because there's parts of the universe that are so far away that light hasn't had chance to reach us from them, and so we haven't seen them and because the universe is expanding and that expansion is accelerating faster than the speed of light, we may never see them. And so there's sort of like a spherical wall past which we cannot see, and past which we may never be able to see or go.
Right, damn, But that's more of a philosophical wall, isn't it? Or do you think maybe it's the same thing.
And let's not get philosophical on the podcast, right, Gosh for bid, we're talking about universal questions. No, I mean it's not fundamental, right, Like, you can imagine that there's a point out there in space beyond which we cannot see, and if we look at that point, we're seeing like the early universe because light is taken forever to get here from there. But it's sort of unsatisfying because there's something recent happening at that point right now. You know, we see old light coming from that point, but you know, stuff's been happening. There's things going on. Galaxies are forming, alien civilizations, hopefully are inventing cool podcasts. So what we're seeing in that direction is always happening now, so we think the universe continues on even though we can only see this aging, observable shell that surrounds us. So in that sense, it's it's observational more than philosophical.
All right, well it sounds like that again. The answer for Eleanor is Daniel doesn't know. Nobody knows.
Daniel doesn't know the new name for our podcast, Daniel doesn't know things. Daniel doesn't know.
Basically, nobody knows. Right, I feel like we don't know what a very fun theame mental level, like it could be infinite or it could not be infinite. And there's a big difference between infinity and non infinity.
And that's the joy of these questions. That the questions that children ask, the very basic questions, the first questions that come into your mind when you hear about these ideas, those are questions scientists are still asking. So if you're six years old or you're sixty years old and you're on the forefront of cosmology, you're asking the same questions. And that's what makes physics shockingly accessible. I would say that our cluelessness, our lack of progress, makes us accessible.
Yeah, Or if you're six hundred years old and an alien and do have the answers to these questions, please let us know, so I can tell Eleanor what the answer is.
But that's one of the reasons why we wanted to make this show is that we felt like this kind of curiosity is wonderful and it powers scientists in their career, and also it powers children. And we see it in the very youngest children, and we want to nurture it, we want to protect it. Sometimes it feels a little bit fragile, and so in our show, we wanted to encourage this kind of curiosity by showing kids on screen how curious kids can ask questions and how they can find the answers for themselves.
Yeah, and that's why we love the show.
That's why we love the show. And if you like a mix of science and kind of corny dad jokes, then hopefully you'll also.
Like the show. Yeah, So help us celebrate the release and the premiere, at least the US premiere. We're still trying to get the show in other countries. But help us celebrate the US premiere of Eleanor Wonders Why, the show that Daniel and I co created. It's for kids. It's about a cute bunny rabbit and her friends, a bat and an elephant in this really beautiful and gentle but also curious and funny world. And it's out now on Pbskids dot org, slash Eleanor Eli n o R and also the PBS Kids app, and also on Amazon Prime PBS Kids subscription, and also I think they're posting episodes on the Pbskid's YouTube channel, So there are plenty of ways for you to watch the show show and it's all free, and please help us celebrate and tell your friends, your nieces and nephews and grandkids about the show. We think they'll really enjoy it.
That's right. It's a world we created filled with people who are curious, who ask questions, and who find answers to those questions. So if you want to spend half an hour in a gentle world filled with curiosity, please go check it out.
Yeah, and we hope you enjoyed Eleanor's questions today about the multiverse and about the shape of space. It definitely kind of stretches your mind, right, Daniel.
It definitely does. And you know, just because a question comes from a young kid doesn't need it's easy to answer. As we went in today, those are my favorite questions.
We invite Eleanor to a seminar at uc Irvine's physics department. She'll stump everyone.
They're open to the public, so come on in.
All right, Well, 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. When you pop a piece of cheese into your mouth, you're probably not thinking about the environmental impact. But the people in the dairy industry are. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. House US dairy tackling greenhouse gases. Many farms use anaerobic digestors to turn the methane from manure into renewable energy that can power farms, towns, and electric cars. Visit you as dairy dot COM's Last Sustainability to learn more.
There are children, friends, and families walking, riding on passing the roads every day. Remember they are real people with love ones who need them to get home safely. Protect our cyclists and pedestrians because they're people too. Go Safely, California From the California Office of Traffic Safety and Caltrans.
We're just days away from our twenty twenty four iHeartRadio Music Festival, preceded by Capitol.
On the biggest headliners in live music will be taking over to Mobile Arena, Las.
Vegas lost some special surprises and moments you are not going to want to miss. Stream only on Hulu iHeartRadio Music Festival.
And listen on iHeartRadio the most anticipated live music events of the
Year this Friday and Saturday, starting at ten thirty pm Eastern, seven thirty Pacific