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Speaker 1: Hey, or hey, if you had to leave a Yelp

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Speaker 1: rating or for the universe, what would you give it?

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Speaker 2: Can I give it like a trillion trillion stars?

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Speaker 1: I think that might break their database. But I'm guessing

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Speaker 1: you're saying that the universe is pretty great.

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Speaker 2: Yeah, it's pretty great in a lot of ways.

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Speaker 1: Right, you mean great is in it's awesome.

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Speaker 2: It's awesome, and it's also really big. It's a great

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Speaker 2: big universe.

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Speaker 1: Hey, that's a catchy phrase.

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Speaker 2: Yeah, somebody should use it for the title of a

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Speaker 2: new book.

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Speaker 1: That's a great big idea.

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Speaker 2: Hi am Poorham, a cartoonist and the author of the

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Speaker 2: new book Oliver is Great, Big Universe.

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Speaker 1: Hi. I'm Daniel. I'm a particle physicist, and I also

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Speaker 1: think the universe is pretty great and big.

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Speaker 2: It's a great big universe.

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Speaker 1: Great also means big, doesn't it? Or isn't that part

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Speaker 1: of the etymology of great?

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Speaker 2: I think technically can mean several things, like it's great,

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Speaker 2: like you like it, but also like it's great, like it's.

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Speaker 1: Big, Yeah, like great Britain. Right, it's pretty great and

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Speaker 1: also big and pretty British. But anyways, welcome to our podcast.

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Speaker 1: Daniel and Jorge Explain the Universe, a production of iHeartRadio

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Speaker 1: in which we try to accomplish a feat which sounds impossible,

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Speaker 1: to download the entirety of this great, big universe into

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Speaker 1: your mind, to summarize all of the whizzing and banging

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Speaker 1: and frothing and tewing and frowing of the tiny little

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Speaker 1: particles that make up this universe into a mathematical story

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Speaker 1: that somehow makes sense to these grown up apes.

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Speaker 2: That's right, because it is a great, big universe full

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Speaker 2: of amazing facts that we like to talk about here

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Speaker 2: on this podcast, and also rate I guess with stars.

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Speaker 1: The universe is definitely filled with stars, big glowing stars

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Speaker 1: and also you know, blowing up pop stars.

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Speaker 2: Well, hopefully I'm not literally blowing up, but it is

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Speaker 2: filled with stars, planets, asteroids, galaxies, dark matter, dark energy,

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Speaker 2: and also people young and old. We're here to ask

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Speaker 2: questions and also sometimes answer them about the universe.

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Speaker 1: That's right. We think everybody should be curious about the universe.

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Speaker 1: When you stare up at the night sky, we want

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Speaker 1: to know what makes you wonder, What questions do you

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Speaker 1: have about how it all works? Not just the earth

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Speaker 1: that's under our feet, but the whole big, great universe

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Speaker 1: out there.

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Speaker 2: Yeah, and speaking of great big universe, we are here

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Speaker 2: to celebrate the release of my new book called Oliver's

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Speaker 2: Great Big Universe, which is out now and you can

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Speaker 2: go out and buy it.

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Speaker 1: Yeah, congratulations. Tell us a little bit about the book

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Speaker 1: and why you wrote it.

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Speaker 2: Yeah, it's an awesome book. It's maybe the only book

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Speaker 2: that is endorsed by Jeff Kinney, the author of Diary

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Speaker 2: of a Wimpy Kit, and also Carlo Rovelli, the theoretical physicists.

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Speaker 1: That's quite a collection. Do you have to be a

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Speaker 1: cartoonist or a theoretical physicist to read it?

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Speaker 2: Absolutely not. I actually wrote the book for kids who

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Speaker 2: wouldn't normally pick up a science book, and also for

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Speaker 2: anyone out there who's interested about the universe. Yeah.

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Speaker 1: Tell us a little bit about your approach. How do

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Speaker 1: you attract people who aren't usually into science.

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Speaker 2: Well, the book again is called Oliver's Great Big Universe,

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Speaker 2: and it's about the story of this eleven year old

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Speaker 2: kid named Oliver, who one day decides he wants to

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Speaker 2: be an astrophysicist, but of course, being eleven years old,

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Speaker 2: he doesn't quite know what that means, and so the

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Speaker 2: whole story is about him trying to figure that out

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Speaker 2: and also him explaining to other kids all of these

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Speaker 2: amazing facts about the universe. So there's chapters about black holes,

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Speaker 2: there's a chapter about dark matter and dark energy. There

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Speaker 2: are chapters about the planets, and there are chapters about

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Speaker 2: the time as well.

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Speaker 1: And don't you, by coincidence, have an eleven year old

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Speaker 1: named Oliver.

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Speaker 2: Yes, it is not a big coincidence. So the whole

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Speaker 2: book was kind of inspired by my son when he

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Speaker 2: was in fifth grade. He came home one day and

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Speaker 2: at the dinner table he announced he wanted to be

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Speaker 2: an astrophysicist, and so we were like, do you know

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Speaker 2: what that means? And he's like, I have no idea,

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Speaker 2: and yeah, that of like confidence and shuitspa and curiosity

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Speaker 2: is kind of what inspired the whole book.

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Speaker 1: So what's it like when a cartoonist has his son

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Speaker 1: saying I want to be a physicist. Is that like

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Speaker 1: when a physicist has a son who says I want

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Speaker 1: to be an artist?

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Speaker 2: Yeah? Kinda? Are you gonna go no? No, it's cool.

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Speaker 2: He's always been kind of a science kid. He's always

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Speaker 2: been interested in science. He's in the math teams, in

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Speaker 2: the Science Olympics team, and so it wasn't super surprising

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Speaker 2: that he says that he wants to be an as

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Speaker 2: a physicist. But it's pretty cool. Yeah, we try to

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Speaker 2: encourage it, for sure.

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Speaker 1: Awesome. Well, something we encourage in our podcast listeners and

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Speaker 1: their kids is asking questions, is thinking about the universe,

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Speaker 1: is wondering if they want to be an after a

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Speaker 1: physicist when they grow up and what exactly that entails.

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Speaker 1: And step number one of being an after physicist is

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Speaker 1: just looking up at the night sky and wondering what's

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Speaker 1: out there, how does it all work? What is in

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Speaker 1: our great, big universe?

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Speaker 2: Yeah, and so to celebrate the release of the new book,

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Speaker 2: we are answering listener questions from kids today.

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Speaker 1: That's right. I went out there and asked our listeners

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Speaker 1: to ask their kid kids what questions they had about

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Speaker 1: the universe. And so today we'll be tackling a few

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Speaker 1: of those.

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Speaker 2: That's always a risky thing to ask your kids what

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Speaker 2: kind of questions they have or did you make it

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Speaker 2: specific about the universe?

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Speaker 1: I made it specific about the universe, which makes it

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Speaker 1: totally generic.

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Speaker 2: I guess the universe is everything, even the uncomfortable parts.

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Speaker 1: Ask me a question, but only about anything in the universe.

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Speaker 2: Right, So we have several questions here from kids about

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Speaker 2: all kinds of things about the universe, from suns and

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Speaker 2: black holes to the infinity of the universe. So the

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Speaker 2: first question comes from Violet. The cause of sun is

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Speaker 2: still a star until one day collapse like other stars

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Speaker 2: and turn into a black hole. Mmmm. That is a

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Speaker 2: deep question from a small mind.

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Speaker 1: I love. Even in that brief question, you can hear

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Speaker 1: her train of thought. She's connecting our star to other stars.

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Speaker 1: She knows that other stars collapse into black holes, and

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Speaker 1: then she was reflecting that knowledge back here and wondering

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Speaker 1: about the fate of our star. All the connection she's making,

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Speaker 1: all the physics you can hear happening in her brain.

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Speaker 2: Yeah, it's pretty awesome. And the sun is something I

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Speaker 2: think all kids can relate to, right, I mean, everyone

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Speaker 2: sees it every day, maybe not directly, but we're all

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Speaker 2: basking and its light.

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Speaker 1: I don't know, she sounded like she had an accent.

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Speaker 1: She might not see the sun that often out in

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Speaker 1: Great Britain. It's pretty cloudy.

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Speaker 2: M Well, some parts of it are, sonny, aren't they.

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Speaker 1: Let's hope.

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Speaker 2: So I do have a whole chapter in Oliver's Great

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Speaker 2: Piginius about the Sun, which it's a nice coincidence. It's

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Speaker 2: kind of fun to explain it in terms that kids

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Speaker 2: can't understand. And so let's dig into violid question here.

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Speaker 2: She wants to know if our sun is going to

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Speaker 2: collapse into a black hole, because I guess she said

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Speaker 2: that other stars collapse into a black hole.

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Speaker 1: Yeah, there are a lot of black holes out there,

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Speaker 1: sort of two varieties are the kind of the center

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Speaker 1: of galaxies, which are called super massive black holes, really

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Speaker 1: really big ones, and nobody really knows where those come from.

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Speaker 1: It's kind of a mystery. But then there's lots of

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Speaker 1: smaller black holes out there which come from stars at

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Speaker 1: the end of their life. These stars have collapsed into

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Speaker 1: a black hole. And so she's wondering about those. And

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Speaker 1: black hole is the endpoint of some stars. Not every

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Speaker 1: star is going to end up as a black hole.

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Speaker 1: And to understand why some stars become black holes and

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Speaker 1: others don't, you have to understand something about the balance

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Speaker 1: of forces that are keeping a star burning in the

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Speaker 1: first place.

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Speaker 2: Yeah, I guess it's a big point to know that

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Speaker 2: not all stars are the same. They're all different, and

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Speaker 2: they mostly differ in size, right, and like the amount

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Speaker 2: of stuff that's in them.

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Speaker 1: Yeah, stars come from the collapse of a big cloud

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Speaker 1: of dust and gas that forms a denser blob. But

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Speaker 1: a cloud can sometimes make lots of stars, and you

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Speaker 1: can get smaller stars or more massive stars. It depends

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Speaker 1: a little bit on the configuration and whether there was

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Speaker 1: like a supernova shockway that triggered it, and whether you

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Speaker 1: had like a cluster of heavy metals in the center

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Speaker 1: to gather stuff more rapidly. So there's a big variation.

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Speaker 1: The bigger stars are less likely and they burn hotter

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Speaker 1: and shorter, and the smaller stars are much more common

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Speaker 1: and they can burn for a long time.

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Speaker 2: And as you said, it's kind of a balance of

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Speaker 2: fusion and gravity, Like there's stuff exploding in the middle,

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Speaker 2: but there's also gravity trying to squeeze the whole thing down. Right.

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Speaker 1: Gravity is what gets things started. You tug a little

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Speaker 1: pebble here and a little bit of cosmic dust over there,

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Speaker 1: and then you get this runaway effect where it gets

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Speaker 1: stronger and stronger gathering stuff together. And if there was

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Speaker 1: only gravity, then any accumulation of stuff would turn into

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Speaker 1: a black hole because it'd be nothing stopping it from

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Speaker 1: getting infinitely dense. But there are other things in the

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Speaker 1: universe than just gravity, Like the Earth doesn't collapse into

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Speaker 1: a black hole. You don't collapse into a black hole

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Speaker 1: because your body or the Earth's structure is strong enough

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Speaker 1: to push against that gravity. Gravity is a huge force

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Speaker 1: in the universe, but it's not very powerful, so it's

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Speaker 1: not actually that hard to overcome.

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Speaker 2: Yeah, but on a sun, that what keeps the whole sun,

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Speaker 2: the whole cloud of gas from collapsing, is fusion, right,

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Speaker 2: it's the nuclear reactions that are happening in the middle exactly.

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Speaker 1: We call it a radiation pressure. That fusion is like

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Speaker 1: an explosion. It's shooting out photons, it's pushing out on

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Speaker 1: all the stuff. And that balance is the gravity of

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Speaker 1: the star. It's sort of amazing that those things can

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Speaker 1: be in balance and be in balanced for so long.

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Speaker 1: Stars can burn for millions or billions. We think some

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Speaker 1: small ones might even burn for trillions of years. It's

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Speaker 1: an incredible balancing act.

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Speaker 2: Yeah, it's pretty wild now that I think about it,

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Speaker 2: to think that it is stable, right, like it could

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Speaker 2: have been the case that suns and stars are not stable.

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Speaker 2: They could either fizzle out pretty easily, or maybe they

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Speaker 2: could have blown up more easily, exactly.

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Speaker 1: And if you get a star that's big enough, like

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Speaker 1: more than three hundred times the mass of our sun,

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Speaker 1: then it gets so hot and so intense at the

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Speaker 1: core that it really does blow itself apart. They don't

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Speaker 1: last very long. There's an interesting range of masses. As

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Speaker 1: you say, the initial scoop of stuff that you get

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Speaker 1: really determines the outcome. And I guess we're just kind

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Speaker 1: of lucky that there are lots of stars that can

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Speaker 1: burn long enough to make our universe bright.

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Speaker 2: I guess they're sort of like candles, right, Like a

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Speaker 2: candle burns for a long time because it has this

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Speaker 2: kind of balance of that it can burn, but it

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Speaker 2: can't burn too much or too fast exactly.

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Speaker 1: That's why you like to build a candle instead of

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Speaker 1: a bomb. Right.

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Speaker 2: That'd be hard to light up your home with bombs, right.

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Speaker 1: I don't recommend anybody reads Jorge's new book By the

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Speaker 1: Light of Bombs, Please get can those if you don't

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Speaker 1: have light bulbs?

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Speaker 2: Yeah, yeah, or a flashlight as well.

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Speaker 1: That works a little safer exactly. But it's not just

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Speaker 1: radiation pressure that can keep something from collapsing into a

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Speaker 1: black hole, because eventually that radiation pressure gives up when

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Speaker 1: you've burned up all the fuel in your star, when

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Speaker 1: you've turned all that hydrogen into helium or something heavier,

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Speaker 1: then you're not fusing anymore. But even still, not every

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Speaker 1: star that finishes all of its fusion will turn into

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Speaker 1: a black.

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Speaker 2: Hole, right Like, you need to have a certain amount

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Speaker 2: of mass to your star for it to even have

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Speaker 2: a chance at becoming a black hole.

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Speaker 1: Exactly, because there are other forces that can push back

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Speaker 1: against gravity, Like you can make something really really dense,

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Speaker 1: like a neutron star, which you can have like the

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Speaker 1: mass of the Sun with a small radius of just kilometers,

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Speaker 1: and even that is very dense, has a lot of gravity,

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Speaker 1: but there are nuclear forces there. The strong nuclear force

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Speaker 1: is pushing back and preventing it from collapsing into a

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Speaker 1: black hole. So even if you don't have fusion pressure

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Speaker 1: from an active star, you can still avoid collapsing into

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Speaker 1: a black hole just from the chemical forces or the

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Speaker 1: strong nuclear forces.

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Speaker 2: Right now, Violet's question was about our sun. She's wondering

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Speaker 2: if our sun will one day collapse into a black hole,

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Speaker 2: and so what's the answer, yes or no.

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Speaker 1: The answer is almost certainly no, but there is still

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Speaker 1: a lot of uncertainty in exactly how much mass you need.

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Speaker 1: As you said, if you have enough mass, then you

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Speaker 1: have enough gravity. You can overcome all of these forces eventually,

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Speaker 1: the fusion force and the strong nuclear force, and you

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Speaker 1: can collapse into a black hole. But we think that

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Speaker 1: the threshold is somewhere around ten times the mass of

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Speaker 1: the Sun, though it's not something we understand in great detail,

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Speaker 1: and the sort of the consensus number has been moving

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Speaker 1: around a lot.

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Speaker 2: Wait, what you mean, We don't know for sure if

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Speaker 2: our Sun is going to collapse into a black hole.

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Speaker 1: We don't know absolutely for sure, but it's very very unlikely.

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Speaker 1: The smallest black hole we've ever seen is just over

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Speaker 1: three times the mass of the Sun, and it probably

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Speaker 1: came from a star that was more like ten or

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Speaker 1: fifteen times the mass of the Sun. Some calculations say

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Speaker 1: you have to have twenty twenty five times the mass

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Speaker 1: of the Sun. But by looking at black hole mergers,

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Speaker 1: we learned a lot about the sort of minimum black

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Speaker 1: hole mass. It's a lot of interesting stuff still to

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Speaker 1: be learned about this question. But Violet, don't worry.

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Speaker 2: We think our Sun is safe, which means we're safe

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Speaker 2: and she's safe.

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Speaker 1: Although, of course, even though the Sun won't turn into

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Speaker 1: a black hole, that doesn't mean it'll be a fun

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Speaker 1: place to live in about five billion years when it

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Speaker 1: expands into a red super giant and fries the.

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Speaker 2: Earth boy, wait to setter at ease. There, we we

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Speaker 2: just ask her a question and she's like phew, and

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Speaker 2: then you drop the bond.

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Speaker 1: Well, you know, budding astrophysicists got to learn that the

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Speaker 1: universe is a scary place.

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Speaker 2: But the basic answer for Violet is that our Sun

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Speaker 2: doesn't have enough mass, we think, to ever collapse into

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Speaker 2: a black hole. So what's going to happen to our

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Speaker 2: Sun is just going to keep burning forever.

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Speaker 1: It's not going to burn forever. A lot of helium

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Speaker 1: will accumulate its core, which will move the burning more

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Speaker 1: to the exterior, which will puff up the Sun, so

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Speaker 1: it'll grow to be a super giant, a big red star.

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Speaker 1: Then will blow off its outer layers and they'll leave

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Speaker 1: behind a hot core. So probably the Sun will become

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Speaker 1: a white dwarf, which basically just means it leaves behind

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Speaker 1: a big blob of hot metal.

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Speaker 2: It'll just be sort of like a big ball of

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Speaker 2: metal glowing in the dark.

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Speaker 1: Yeah, exactly.

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Speaker 2: Well, hopefully by then a Violet will have invented a

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Speaker 2: warp drive or something, or a wormhole maybe, because Violet

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Speaker 2: sounds pretty smart. And by then we'll be expanding into

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Speaker 2: other solar systems.

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Speaker 1: That's right. Our whole generation of astrophysicists inspired by your

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Speaker 1: book will save humanity. Yeah.

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Speaker 2: And then I'll get all the credit right.

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Speaker 1: And the royalties, right, you get some of those patents right?

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Speaker 2: Yes, I'm going to say yes, and then have the

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Speaker 2: lawyers figure it out. All right. Well, let's get to

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Speaker 2: more questions from kids about this great big universe. But

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Speaker 2: first let's take a quick great or right. We're answering

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Speaker 2: kids questions here today about the universe to celebrate the

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Speaker 2: release of my new book, Oliver's Great Big Universe. Now, Daniel,

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Speaker 2: what kinds of books did you read when you were

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Speaker 2: a kid? Did you read any physics books?

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Speaker 1: Hmmm, oh, great question. When I was eleven, I was

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Speaker 1: definitely reading a lot of science fiction books, and I

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Speaker 1: definitely watched a lot of like nova and documentaries on TV,

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Speaker 1: and I gobbled up like big picture books with drawings

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Speaker 1: with artists impressions of black holes and stuff like that.

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Speaker 2: Yeah, and so today, to mark the release of the book,

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Speaker 2: we're answering listener questions and specifically from kids. And so

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Speaker 2: our next question comes from James and his dead.

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Speaker 3: Hi, Daniel and Joge. This is Paul from Manchester in England.

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Speaker 3: My son James likes thinking about the implications of an

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Speaker 3: infinite universe. In particular, he has this idea that's in

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Speaker 3: an infinite universe, anything that could possibly have happened must

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Speaker 3: have happened an infinite number of times. He was talking

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Speaker 3: to me about this recently and it led me to

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Speaker 3: wonder whether we can say that if the universe is

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Speaker 3: inf it must not be possible to make a machine

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Speaker 3: to travel cosmic scale distances very quickly, because if it

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Speaker 3: was possible to build such a machine, then in an

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Speaker 3: infinite universe, an infinite number of alien civilizations would have

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Speaker 3: done it, and our planet would inevitably have been colonized

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Speaker 3: by aliens. James and I look forward to hearing your

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Speaker 3: thoughts on this. Thanks very much.

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Speaker 2: Oh my goodness, this kid, James should write his own book.

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Speaker 2: What an awesome idea. Can we just give him a

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Speaker 2: Nobel prize.

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Speaker 1: A Nobel Prize for arguing that a breakthrough is not possible.

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Speaker 2: And a Noble price just for blowing my mind? What

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Speaker 2: an interesting question.

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Speaker 1: Yeah, it is a really ingenious idea, all.

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Speaker 2: Right, So let's break it down. So I think James

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Speaker 2: is saying that if faster than light travel was possible

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Speaker 2: and the universe is infinite, then by now some alien

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Speaker 2: civilization with faster than light travel should have visited us.

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Speaker 1: But by now, yeah, I think think that's the argument.

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Speaker 1: It's sort of similar to saying, if time travel is possible,

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Speaker 1: somebody in the future would have discovered it and then

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Speaker 1: come back to visit us, and so since they haven't,

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Speaker 1: therefore time travel is not possible. Except in this case,

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Speaker 1: he's reflecting that argument into space and imagining somebody out

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Speaker 1: there must have figured out faster than light travel and

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Speaker 1: if they had, they would have come visited us, and

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Speaker 1: they haven't, so therefore maybe it's impossible.

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Speaker 2: Right. What do you call that kind of argument? Is

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Speaker 2: there a name for it?

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Speaker 1: Clever? Clever argument from desperation?

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Speaker 2: I don't know, And I've heard this argument before, like

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Speaker 2: there's no time travel because otherwise there would be time

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Speaker 2: travelers visiting us right now. But I always feel like

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Speaker 2: that's assuming we live in an interesting time.

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Speaker 1: But if there's an infinite future for humanity, then somebody

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Speaker 1: will find us interesting.

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Speaker 2: Right well, I feel like it's sort of like if

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Speaker 2: you're in a really bad place and you're like, there

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Speaker 2: must not be any tourists in the world, because we

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Speaker 2: never get tourists here. That's really just says something about

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Speaker 2: where you live.

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Speaker 1: But if there were an infinite number of tourists, somebody

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Speaker 1: would think that your boring street was fascinating. I think

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Speaker 1: that's the crux of his argument. It really relies on

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Speaker 1: this idea of infinity. In the power of infinity.

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Speaker 2: Right right, unless your plate you live in an infinitely

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Speaker 2: boring place, in case it cancels out, what's infinitely divided

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Speaker 2: by infinity.

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Speaker 1: Theologians have been thinking about infinitely powerful forces and infinitely

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Speaker 1: strong walls, but you're thinking about infinitely boring places and

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Speaker 1: infinite numbers of tourists.

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Speaker 2: Yeah, you know, that's what this podcast is all about,

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Speaker 2: great big ideas.

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Speaker 1: That's right. Well, there's a lot of really interesting ideas

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Speaker 1: in James's argument. The first one is essentially that if

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Speaker 1: the universe is infinite. Anything that can happen will happen,

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Speaker 1: and that's how we get the idea that if fast

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Speaker 1: and light travel is possible, somebody out there will develop it.

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Speaker 1: And that's a subtle idea.

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Speaker 2: Actually, it's pretty interesting, right to think there might be

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Speaker 2: an infinite number of alien civilizations, and if it was possible,

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Speaker 2: one of them must surely have invented war price.

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Speaker 1: Yeah, and if you take it literally, it doesn't just

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Speaker 1: imply an infinite number of alien civilizations and implies an

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Speaker 1: infinite number of human civilizations, right, because if humanity can evolve,

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Speaker 1: which obviously it can because it has and space is infinite,

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Speaker 1: that would suggest that it's happening somewhere else actually an

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Speaker 1: infinite number of times.

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Speaker 2: But do they have to be humans? Couldn't they be

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Speaker 2: like tentacled aliens that invent the warp drive?

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Speaker 1: No, they don't have to be humans. I think it's

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Speaker 1: actually weirder if there are more humans out there totally

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Speaker 1: independently evolved than like weirdly tentacled aliens.

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Speaker 2: Although technically, in an infinite universe, wouldn't you also get

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Speaker 2: an infinite number of human civilizations?

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Speaker 1: Yeah? Exactly, you get an infinite number of everything that's possible.

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Speaker 2: And virtually possible because we're here.

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Speaker 1: Yeah, exactly, So you would have an infinite number of

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Speaker 1: James Is asking an infant number of questions on an

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Speaker 1: infinite number of podcasts.

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Speaker 2: All right, So then how would you answer that or

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Speaker 2: how would you break down the infinity argument.

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Speaker 1: I think it's a pretty strong argument, but there are

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Speaker 1: some holes. Here's some nuances, and one is on the

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Speaker 1: issue of infinity. It's true that anything with a finite

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Speaker 1: probability will happen an infinite number of times if you

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Speaker 1: get an infinite number of tries, Like if you have

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Speaker 1: some huge die with a billion sides to it, it

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Speaker 1: doesn't really matter how many billion sides there are. If

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Speaker 1: you get to roll an infinite number of times, eventually

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Speaker 1: every side will come up. So that part is true.

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Speaker 1: But when you apply that to anything could happen in

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Speaker 1: the universe, there's a little wrinkle there, which is that

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Speaker 1: you need the right initial conditions. Imagine an infinite universe,

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Speaker 1: for example, that's just smooth and has no features, no

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Speaker 1: structure to it, no stars ever form, no galaxies ever form.

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Speaker 1: That's an infinite universe. But you don't get every outcome,

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Speaker 1: because the outcomes are determined by the initial conditions. You

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Speaker 1: have to have like the right configuration for things to

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Speaker 1: start from, which determines essentially what is possible.

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Speaker 2: Yeah, I guess you have to assume that the rest

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Speaker 2: of the infinite universe is just like the universe that

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Speaker 2: we see around us, which may not be the case.

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Speaker 1: Which may not be the case exactly, But you could

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Speaker 1: also imagine that maybe in order to develop faster than

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Speaker 1: like travel, some alien civilization needs a very different set

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Speaker 1: of conditions than the kind we have here. You're much

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Speaker 1: stronger curvature, So these aliens grow up with a native

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Speaker 1: understanding of space time and can therefore manipulate it. Maybe

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Speaker 1: they need to be like a planet inside a black hole. Right,

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Speaker 1: It's possible inside super massive black holes to have stable

441
00:20:22,119 --> 00:20:24,600
Speaker 1: orbits and people are speculated you could have life evolve

442
00:20:24,680 --> 00:20:27,040
Speaker 1: inside of it. But a species that evolves inside a

443
00:20:27,040 --> 00:20:30,240
Speaker 1: black hole, they couldn't even use their FTL travel to

444
00:20:30,359 --> 00:20:30,840
Speaker 1: reach us.

445
00:20:31,600 --> 00:20:35,080
Speaker 2: WHOA, But I think that doesn't affect James's question, right,

446
00:20:35,200 --> 00:20:37,639
Speaker 2: Like we know that the conditions surround us are possible.

447
00:20:37,800 --> 00:20:39,760
Speaker 1: I think it's true that if the universe is infinite

448
00:20:39,800 --> 00:20:42,399
Speaker 1: and filled with infinite stuff. There's an infinite number of

449
00:20:42,440 --> 00:20:46,000
Speaker 1: human civilizations and maybe also infinite alien civilizations. But it

450
00:20:46,040 --> 00:20:48,960
Speaker 1: might be that FTL travel is possible, is allowed by

451
00:20:48,960 --> 00:20:51,439
Speaker 1: the laws of physics, but that none of the infinite

452
00:20:51,480 --> 00:20:54,639
Speaker 1: number of human civilizations discover it either, because the conditions

453
00:20:54,680 --> 00:20:57,040
Speaker 1: in which we grow up, in which we evolve don't

454
00:20:57,080 --> 00:21:00,840
Speaker 1: give us a sort of natural intuition to manipulate space time,

455
00:21:01,119 --> 00:21:04,080
Speaker 1: because we're like not near enough black holes to experience that.

456
00:21:04,400 --> 00:21:06,200
Speaker 2: Well, But isn't that a bit of a stretch of

457
00:21:06,240 --> 00:21:08,600
Speaker 2: an argument. I mean, we can still discover it. We

458
00:21:08,640 --> 00:21:10,640
Speaker 2: don't have to be living inside of a black hole

459
00:21:10,800 --> 00:21:13,080
Speaker 2: for us right now to understand what it's like to

460
00:21:13,160 --> 00:21:13,960
Speaker 2: live in a black hole.

461
00:21:14,040 --> 00:21:15,919
Speaker 1: Yeah, that's right. It's possible that we could in the

462
00:21:15,920 --> 00:21:19,040
Speaker 1: future discover FTL travel. My point is essentially that there's

463
00:21:19,080 --> 00:21:22,200
Speaker 1: some limitations to the possible outcomes. You have an infinite

464
00:21:22,320 --> 00:21:24,520
Speaker 1: number of roles that die, but the die might have

465
00:21:24,640 --> 00:21:28,400
Speaker 1: some limitations on those possible outcomes based on the configuration

466
00:21:28,560 --> 00:21:32,280
Speaker 1: of space. Not everything that is possible actually does happen,

467
00:21:32,600 --> 00:21:35,520
Speaker 1: only things that are possible, and that our potential outcomes

468
00:21:35,560 --> 00:21:39,240
Speaker 1: from the initial conditions of the universe, like For example,

469
00:21:39,480 --> 00:21:42,919
Speaker 1: having the entire universe collapse into a black hole physically

470
00:21:43,080 --> 00:21:46,440
Speaker 1: possible is something against the laws of physics from that configuration,

471
00:21:46,680 --> 00:21:49,360
Speaker 1: but you can't get to that configuration from here. There's

472
00:21:49,400 --> 00:21:52,479
Speaker 1: lots of things between you and that arrangement of stuff

473
00:21:52,520 --> 00:21:56,240
Speaker 1: in the universe. So not every arrangement that's physically possible

474
00:21:56,280 --> 00:21:59,440
Speaker 1: will actually be realized by our universe because we start

475
00:21:59,480 --> 00:22:00,800
Speaker 1: from a certain configuration.

476
00:22:01,240 --> 00:22:03,600
Speaker 2: But then in an infinite universe, don't you get all

477
00:22:03,920 --> 00:22:06,240
Speaker 2: infinite possible starting conditions?

478
00:22:06,480 --> 00:22:08,880
Speaker 1: Yes, great question. We don't know, right because we don't

479
00:22:08,920 --> 00:22:12,439
Speaker 1: really understand the starting configurations of our universe. We know

480
00:22:12,520 --> 00:22:15,800
Speaker 1: that we had a fairly smooth universe with some quantum fluctuations,

481
00:22:15,960 --> 00:22:18,480
Speaker 1: we don't really know exactly where those came from and

482
00:22:18,520 --> 00:22:20,880
Speaker 1: what came before that, so we don't know if we've

483
00:22:20,920 --> 00:22:25,199
Speaker 1: like really explored the full range of possible initial configurations,

484
00:22:25,480 --> 00:22:28,040
Speaker 1: or if we're only getting a little slice, or maybe

485
00:22:28,040 --> 00:22:31,080
Speaker 1: elsewhere in the universe they got different initial configurations. We

486
00:22:31,280 --> 00:22:31,879
Speaker 1: just don't know.

487
00:22:32,200 --> 00:22:34,280
Speaker 2: I guess I think James is saying, if it is

488
00:22:34,359 --> 00:22:38,119
Speaker 2: possible for humans at least to come up with faster

489
00:22:38,200 --> 00:22:40,680
Speaker 2: than light travel, then if there are infinite number of

490
00:22:40,720 --> 00:22:43,160
Speaker 2: humans out there, then they must have surely discovered it.

491
00:22:43,240 --> 00:22:46,520
Speaker 2: Just because it's maybe more likely for black hole aliens

492
00:22:46,560 --> 00:22:48,600
Speaker 2: to discover it doesn't mean that we can't discover it

493
00:22:48,680 --> 00:22:50,720
Speaker 2: or that it's not possible, right, because it's the same

494
00:22:50,760 --> 00:22:51,720
Speaker 2: loss of physics, isn't it.

495
00:22:51,760 --> 00:22:54,520
Speaker 1: Yeah, that's right. If it's possible for humans to discover

496
00:22:54,680 --> 00:22:57,080
Speaker 1: FTL travel, then I think you're right. In an infinite

497
00:22:57,200 --> 00:23:00,000
Speaker 1: universe they will. But there's a difference between is FTL

498
00:23:00,160 --> 00:23:03,119
Speaker 1: travel allowed by the laws of physics and is it

499
00:23:03,200 --> 00:23:06,480
Speaker 1: possible for humans to discover it. Another possibility is the

500
00:23:06,560 --> 00:23:10,440
Speaker 1: universe allows faster than light travel by some crazy warped technology,

501
00:23:10,760 --> 00:23:13,880
Speaker 1: but humans are just not smart enough to figure it out.

502
00:23:13,880 --> 00:23:17,200
Speaker 1: That it's not discoverable by us and any of our

503
00:23:17,200 --> 00:23:20,280
Speaker 1: infinite brethren because it just requires like much more mental

504
00:23:20,280 --> 00:23:22,000
Speaker 1: computing power than we're capable of.

505
00:23:22,240 --> 00:23:24,720
Speaker 2: Hmm. But that's why we build the eyes.

506
00:23:26,680 --> 00:23:30,399
Speaker 1: Yeah, that's a great point. So like machine augmented human

507
00:23:30,480 --> 00:23:34,159
Speaker 1: intelligence might not have the same kind of limitations, So

508
00:23:34,200 --> 00:23:36,760
Speaker 1: that's a way around that argument. So yeah, it's a

509
00:23:36,800 --> 00:23:39,480
Speaker 1: really interesting, I think, quite powerful argument. There are a

510
00:23:39,480 --> 00:23:41,919
Speaker 1: few nuances and subtleties there, but I think he's right

511
00:23:41,960 --> 00:23:43,919
Speaker 1: that we can say a lot about the likelihood of

512
00:23:44,000 --> 00:23:46,760
Speaker 1: FTL travel from the fact that we haven't been visited.

513
00:23:46,960 --> 00:23:49,120
Speaker 1: Or maybe you're right and our corner of Earth is just.

514
00:23:49,080 --> 00:23:53,000
Speaker 2: Too boring, infinitely boring. Well, I think the other big

515
00:23:53,040 --> 00:23:56,600
Speaker 2: limitation is just time, Like, maybe you need more time

516
00:23:56,760 --> 00:24:00,560
Speaker 2: for any of these infinitializations to come up faster than

517
00:24:00,640 --> 00:24:03,359
Speaker 2: light travel, and maybe the universe is just not old enough.

518
00:24:03,440 --> 00:24:05,600
Speaker 2: You sort of also need infinite time, right.

519
00:24:05,640 --> 00:24:07,720
Speaker 1: You definitely need time, but how much time you need

520
00:24:07,760 --> 00:24:10,480
Speaker 1: depends a little bit on like how fast this faster

521
00:24:10,560 --> 00:24:13,040
Speaker 1: than light travel is. If you can go anywhere in

522
00:24:13,080 --> 00:24:15,679
Speaker 1: the universe in a moment, like with a wormhole, then

523
00:24:15,680 --> 00:24:19,240
Speaker 1: you're really visitable from anywhere in the infinite universe. And

524
00:24:19,560 --> 00:24:22,879
Speaker 1: you know, the universe is pretty old. Fourteen billion years

525
00:24:22,960 --> 00:24:25,240
Speaker 1: is a long time. We're sort of late in the

526
00:24:25,280 --> 00:24:27,600
Speaker 1: era of the universe. Our solar system has only been

527
00:24:27,640 --> 00:24:31,200
Speaker 1: around for a few billion years. So in an infinite universe,

528
00:24:31,240 --> 00:24:34,720
Speaker 1: there will have been civilizations that started billions and billions

529
00:24:34,800 --> 00:24:37,800
Speaker 1: of years ago and certainly have had time to reach us.

530
00:24:37,920 --> 00:24:40,600
Speaker 2: Yeah, or maybe not right, Like, maybe you need more time, right,

531
00:24:40,640 --> 00:24:42,639
Speaker 2: And the other thing I was thinking about is that

532
00:24:42,680 --> 00:24:44,680
Speaker 2: if it is an infinite universe, that means there are

533
00:24:44,760 --> 00:24:48,080
Speaker 2: an infinite number of places you can go, which means

534
00:24:48,119 --> 00:24:51,200
Speaker 2: like the likelihood that some an alien civilization with faster

535
00:24:51,280 --> 00:24:54,000
Speaker 2: than light travel would come to our planet is almost

536
00:24:54,040 --> 00:24:56,199
Speaker 2: like infinitely small, too, isn't it.

537
00:24:56,880 --> 00:24:58,960
Speaker 1: Yeah, there's a lot of infinities here. You tackle a

538
00:24:58,960 --> 00:25:00,720
Speaker 1: lot of similar ideas when you think just about the

539
00:25:00,760 --> 00:25:04,560
Speaker 1: more standard Fermi paradox, like the galaxy is pretty old

540
00:25:04,720 --> 00:25:07,560
Speaker 1: and not that big, why haven't we been visited even

541
00:25:07,600 --> 00:25:10,880
Speaker 1: without FTL travel? Because it only takes like a few

542
00:25:10,920 --> 00:25:13,920
Speaker 1: tens of thousands of years to explore the whole galaxy,

543
00:25:14,320 --> 00:25:17,000
Speaker 1: either with like self replicating probes or even a small

544
00:25:17,000 --> 00:25:19,399
Speaker 1: fleet of ships. So I think the same math holds

545
00:25:19,440 --> 00:25:22,280
Speaker 1: there that an infinite universe, you should have an infinite

546
00:25:22,400 --> 00:25:25,480
Speaker 1: number of aliens with FTL travel, and eventually some of

547
00:25:25,480 --> 00:25:28,240
Speaker 1: them should reach us. And given how old the universe is,

548
00:25:28,280 --> 00:25:30,560
Speaker 1: it is a little odd that we haven't been visited.

549
00:25:30,680 --> 00:25:33,440
Speaker 2: Yeah, And the other counter argument to James's idea here,

550
00:25:33,480 --> 00:25:35,199
Speaker 2: I feel like it's like, how do you know we

551
00:25:35,240 --> 00:25:38,520
Speaker 2: haven't been visited by aliens with faster than like travel?

552
00:25:38,640 --> 00:25:40,280
Speaker 2: You know, like, how do you know I'm not a

553
00:25:40,440 --> 00:25:41,679
Speaker 2: time traveler from the future.

554
00:25:41,800 --> 00:25:42,040
Speaker 3: Mmm.

555
00:25:42,760 --> 00:25:45,080
Speaker 1: Or maybe James is actually an alien and this is

556
00:25:45,160 --> 00:25:48,160
Speaker 1: his way to sort of introduce subtly the concept into

557
00:25:48,200 --> 00:25:48,919
Speaker 1: the zeitgeist.

558
00:25:49,280 --> 00:25:52,600
Speaker 2: I see, maybe he's an alien and a time traveler.

559
00:25:52,800 --> 00:25:54,600
Speaker 2: Maybe he's an alien from the future.

560
00:25:55,680 --> 00:25:58,840
Speaker 1: James, if you're visiting alien or visiting human from somewhere

561
00:25:58,840 --> 00:26:00,680
Speaker 1: else farw in the universe, I hope you don't find

562
00:26:00,760 --> 00:26:01,439
Speaker 1: us too boring.

563
00:26:01,720 --> 00:26:06,000
Speaker 2: Yeah, I hope he finds us only finitely. All right, Well,

564
00:26:06,080 --> 00:26:08,720
Speaker 2: let's get to more questions from kid listeners. But first

565
00:26:08,800 --> 00:26:24,120
Speaker 2: let's take another quick break. All right, we're answering questions

566
00:26:24,119 --> 00:26:26,640
Speaker 2: from kids to celebrate the release of my new book,

567
00:26:26,760 --> 00:26:29,560
Speaker 2: Oliver's Great Big Universe. Let's get to our last questions

568
00:26:29,560 --> 00:26:33,560
Speaker 2: here from kid listeners. The next one comes from Ida hy.

569
00:26:33,520 --> 00:26:40,120
Speaker 1: Daniel Josh, Would I had special pal inside of black hole?

570
00:26:42,480 --> 00:26:44,480
Speaker 2: Awesome question. I'm going to say the answer is yes.

571
00:26:45,720 --> 00:26:50,720
Speaker 1: Next question, you are the superhero science expert on the podcast.

572
00:26:50,760 --> 00:26:52,479
Speaker 1: You know what kind of special powers would you get

573
00:26:52,520 --> 00:26:53,640
Speaker 1: from being inside a black hole?

574
00:26:53,920 --> 00:26:56,000
Speaker 2: Oh? Boy, I feel like I could write a whole

575
00:26:56,000 --> 00:26:57,119
Speaker 2: other book about this idea.

576
00:26:59,440 --> 00:27:01,359
Speaker 1: Sounds like you and Ida should write that book.

577
00:27:02,960 --> 00:27:06,920
Speaker 2: Itida's great big black hole. Well, then let's see her question.

578
00:27:06,960 --> 00:27:09,400
Speaker 2: Let's break it down. She asked, would she have special

579
00:27:09,480 --> 00:27:12,439
Speaker 2: powers if she was inside a black hole?

580
00:27:12,720 --> 00:27:14,320
Speaker 1: Do you think this is sort of like a bitten

581
00:27:14,320 --> 00:27:16,160
Speaker 1: by a radioactive spider kind of situation?

582
00:27:16,680 --> 00:27:18,920
Speaker 2: Or maybe I think she's saying like, if she lived

583
00:27:18,960 --> 00:27:21,080
Speaker 2: inside of a black hole, would life be the same

584
00:27:21,080 --> 00:27:23,320
Speaker 2: for her? Or would she be able to do things

585
00:27:23,320 --> 00:27:25,120
Speaker 2: she couldn't do outside of the black hole?

586
00:27:25,720 --> 00:27:28,240
Speaker 1: Yeah? I see, Well, there is one way in which

587
00:27:28,280 --> 00:27:30,960
Speaker 1: being inside a black hole would be pretty different from

588
00:27:31,000 --> 00:27:33,199
Speaker 1: living on Earth, and that has to do with the

589
00:27:33,240 --> 00:27:36,640
Speaker 1: flow of time. Right. We know that time goes slower

590
00:27:36,720 --> 00:27:39,840
Speaker 1: when space is curved, the same way that space is curved.

591
00:27:39,920 --> 00:27:43,320
Speaker 1: Near mass's time is essentially also curved. Space and time

592
00:27:43,400 --> 00:27:46,240
Speaker 1: curved together. What that means is, if you're near something really,

593
00:27:46,240 --> 00:27:50,200
Speaker 1: really massive, your time goes slower. Like somebody far out

594
00:27:50,240 --> 00:27:53,359
Speaker 1: in space, their time goes faster than somebody standing on

595
00:27:53,440 --> 00:27:56,440
Speaker 1: Earth and near a black hole or inside a black hole,

596
00:27:56,520 --> 00:27:58,639
Speaker 1: time goes super duper slow.

597
00:27:59,000 --> 00:28:00,879
Speaker 2: How slow to zero.

598
00:28:00,840 --> 00:28:02,800
Speaker 1: It depends a little on the observer. But if you're

599
00:28:02,840 --> 00:28:05,040
Speaker 1: far away from a black hole and you see somebody

600
00:28:05,080 --> 00:28:07,400
Speaker 1: falling into a black hole. You will see their time

601
00:28:07,440 --> 00:28:10,000
Speaker 1: go slower and slower, so that you'll never actually even

602
00:28:10,040 --> 00:28:12,840
Speaker 1: see them cross over into the black hole because their

603
00:28:12,880 --> 00:28:15,919
Speaker 1: time will slow down so much. They'll sort of asymptotically

604
00:28:16,160 --> 00:28:18,680
Speaker 1: approach the black hole from their point of view. They

605
00:28:18,720 --> 00:28:21,000
Speaker 1: will fall in the black hole, and they will see

606
00:28:21,040 --> 00:28:24,280
Speaker 1: your clocks speed up by how much depends on the

607
00:28:24,320 --> 00:28:26,399
Speaker 1: mass of the black hole that you're falling into.

608
00:28:27,080 --> 00:28:28,960
Speaker 2: I see. So the power you get by falling into

609
00:28:29,000 --> 00:28:31,080
Speaker 2: a black hole is you get to fast forward the

610
00:28:31,119 --> 00:28:31,960
Speaker 2: rest of the universe.

611
00:28:32,119 --> 00:28:34,439
Speaker 1: Yeah, you get to fast forward the rest of the universe.

612
00:28:34,480 --> 00:28:36,480
Speaker 2: Like if it's infinitely boring, you can just be like.

613
00:28:36,560 --> 00:28:42,600
Speaker 1: Skip exactly that button that says like skip intro or skip.

614
00:28:42,320 --> 00:28:47,760
Speaker 2: Recap, skip everything. I just want to see the credits.

615
00:28:47,560 --> 00:28:49,960
Speaker 1: Exactly, skip forward to see the credits. And so you'll

616
00:28:50,000 --> 00:28:52,960
Speaker 1: see the rest of the universe going in fast forward.

617
00:28:53,080 --> 00:28:55,080
Speaker 1: You'll see like the end of our star. You'll see

618
00:28:55,080 --> 00:28:58,040
Speaker 1: the collision of our galaxy with other galaxies. All this

619
00:28:58,120 --> 00:29:00,640
Speaker 1: kind of stuff will happen. Now actually see it all

620
00:29:00,640 --> 00:29:03,440
Speaker 1: through just a tiny little pinprick, because if you're actually

621
00:29:03,440 --> 00:29:05,840
Speaker 1: within an event horizon of a black hole, all the

622
00:29:05,920 --> 00:29:07,880
Speaker 1: light in the universe still comes to you, but it

623
00:29:07,880 --> 00:29:10,320
Speaker 1: comes to you through this tiny little dot. Most of

624
00:29:10,360 --> 00:29:12,600
Speaker 1: space is so bent that everything in front of you

625
00:29:12,720 --> 00:29:15,440
Speaker 1: is just the singularity, but there'll be this tiny little

626
00:29:15,480 --> 00:29:18,120
Speaker 1: dot behind you where photons can still make it to

627
00:29:18,200 --> 00:29:21,600
Speaker 1: you and bring you news of the universe you fast forwarded.

628
00:29:22,160 --> 00:29:24,160
Speaker 2: Well. First of all, as we've talked about it before,

629
00:29:24,520 --> 00:29:27,160
Speaker 2: it is possible to go into a black hole, right Like,

630
00:29:27,200 --> 00:29:30,280
Speaker 2: if a black hole is big enough, then its event

631
00:29:30,400 --> 00:29:33,120
Speaker 2: horizon is at a point where you wouldn't necessarily get

632
00:29:33,160 --> 00:29:36,920
Speaker 2: shredded by the gravitational forces. It is possible for someone

633
00:29:37,280 --> 00:29:38,760
Speaker 2: like you and me to go into a black hole.

634
00:29:38,880 --> 00:29:40,600
Speaker 1: Yeah, And as we talked about in our recent book,

635
00:29:40,760 --> 00:29:43,520
Speaker 1: frequently asked questions about the universe, As you get closer

636
00:29:43,520 --> 00:29:46,040
Speaker 1: and closer, the event horizon swells to take up a

637
00:29:46,120 --> 00:29:49,239
Speaker 1: larger and larger portion of your view, eventually takes up

638
00:29:49,320 --> 00:29:51,640
Speaker 1: like half of your view, and then it grows around

639
00:29:51,680 --> 00:29:53,640
Speaker 1: you and then you can only see a tiny little dot.

640
00:29:53,800 --> 00:29:56,560
Speaker 2: But then you could potentially still be conscious and be

641
00:29:56,600 --> 00:29:59,760
Speaker 2: thinking about and experiencing this phenomenon, right like, you'd be

642
00:30:00,160 --> 00:30:02,720
Speaker 2: oh my god, what's going on now? Ida's question is,

643
00:30:02,760 --> 00:30:04,040
Speaker 2: would you have superpowers.

644
00:30:06,040 --> 00:30:07,760
Speaker 1: I think fast forwarding to the end of the universe

645
00:30:07,800 --> 00:30:10,960
Speaker 1: feels like a special power. It's not a superpower in

646
00:30:10,960 --> 00:30:13,640
Speaker 1: the sense that it's not like supernatural doesn't break the

647
00:30:13,760 --> 00:30:15,840
Speaker 1: laws of physics, But I think what physics can do

648
00:30:15,920 --> 00:30:17,720
Speaker 1: is pretty special, so I think it counts as a

649
00:30:17,720 --> 00:30:19,840
Speaker 1: special power even if it's not a superpower.

650
00:30:20,800 --> 00:30:23,040
Speaker 2: I guess, like if you fell into a black hole,

651
00:30:23,120 --> 00:30:25,920
Speaker 2: then you survive, your body wouldn't necessarily change, so you

652
00:30:25,920 --> 00:30:28,680
Speaker 2: wouldn't get the superpowers necessarily. But I wonder if maybe

653
00:30:28,680 --> 00:30:30,600
Speaker 2: Ida's wondering, like, you know, like if you go to

654
00:30:30,640 --> 00:30:33,200
Speaker 2: the moon or moon here, you could jump really high,

655
00:30:33,240 --> 00:30:36,080
Speaker 2: for example, because there's less gravity. Would there be any

656
00:30:36,160 --> 00:30:38,800
Speaker 2: kind of things I could do in a black hole

657
00:30:38,840 --> 00:30:39,760
Speaker 2: I couldn't normally do.

658
00:30:39,960 --> 00:30:41,360
Speaker 1: I think in a black hole you'd never have to

659
00:30:41,360 --> 00:30:43,640
Speaker 1: worry about cleaning up. You could just throw stuff into

660
00:30:43,680 --> 00:30:46,280
Speaker 1: the singularity. You basically never have to take out the trash.

661
00:30:46,480 --> 00:30:50,160
Speaker 2: Yeah, that's a superpower for sure. I'm not sure that

662
00:30:50,640 --> 00:30:54,640
Speaker 2: they'll let you into any adventurous team or anything like that. Yeah,

663
00:30:54,720 --> 00:30:56,840
Speaker 2: but you know, you said earlier that it is possible

664
00:30:56,880 --> 00:30:59,600
Speaker 2: maybe for there to be planets inside of a black hole.

665
00:30:59,680 --> 00:31:02,320
Speaker 2: You know, orbiting a star and stuff. Would life be

666
00:31:02,480 --> 00:31:04,760
Speaker 2: different for them or would it be the same as

667
00:31:04,800 --> 00:31:05,800
Speaker 2: it is for us.

668
00:31:06,000 --> 00:31:08,040
Speaker 1: Life would certainly be different for them, and you could

669
00:31:08,080 --> 00:31:10,560
Speaker 1: check out our podcast episode. I think Katie was our

670
00:31:10,600 --> 00:31:13,600
Speaker 1: co host on that one, because they would see things

671
00:31:13,680 --> 00:31:16,479
Speaker 1: very differently. Right, you wouldn't have any illumination, and your

672
00:31:16,520 --> 00:31:18,640
Speaker 1: planet would be really hot on the inside it be

673
00:31:18,680 --> 00:31:21,720
Speaker 1: squeezed by the tidal forces. It'd be more like living

674
00:31:21,760 --> 00:31:24,160
Speaker 1: on the moon of Jupiter, you know, like Io, which

675
00:31:24,240 --> 00:31:26,600
Speaker 1: is very volcanic, So it'd be a very different kind

676
00:31:26,600 --> 00:31:28,760
Speaker 1: of experience. Kids on that planet wouldn't look up at

677
00:31:28,800 --> 00:31:30,920
Speaker 1: the night sky and see the same things that we see.

678
00:31:30,960 --> 00:31:33,240
Speaker 1: They would see a completely black night sky except for

679
00:31:33,280 --> 00:31:35,960
Speaker 1: a tiny little dot through which they would see everything

680
00:31:35,960 --> 00:31:36,920
Speaker 1: else in the universe.

681
00:31:37,520 --> 00:31:39,400
Speaker 2: Could they see like the hand in front of them?

682
00:31:39,800 --> 00:31:41,280
Speaker 2: Like if I put my hand in front of me

683
00:31:41,320 --> 00:31:43,120
Speaker 2: inside of black hole? Could I see my hand?

684
00:31:43,400 --> 00:31:46,400
Speaker 1: And the outskirts of a super massive black hole. Space

685
00:31:46,480 --> 00:31:49,200
Speaker 1: is not so curved that you couldn't see anything, and

686
00:31:49,240 --> 00:31:51,280
Speaker 1: so it is possible for light to still make some

687
00:31:51,440 --> 00:31:54,720
Speaker 1: progress towards your eyeballs. And the outskirts of a super

688
00:31:54,760 --> 00:31:55,680
Speaker 1: massive black.

689
00:31:55,400 --> 00:31:58,040
Speaker 2: Hole, like you'd be inside, but you'd be near the edge.

690
00:31:58,240 --> 00:32:00,960
Speaker 2: Mm hmm, so maybe you could. You would see your hand,

691
00:32:01,000 --> 00:32:02,840
Speaker 2: but it would all be kind of weird and distorted.

692
00:32:03,040 --> 00:32:05,360
Speaker 1: All of space would be very distorted, so the way

693
00:32:05,400 --> 00:32:07,960
Speaker 1: time would flow would be different. People closer to the

694
00:32:07,960 --> 00:32:10,280
Speaker 1: center of black hole would have their clocks slow down

695
00:32:10,480 --> 00:32:12,760
Speaker 1: compared to people further from the center of the black hole.

696
00:32:13,000 --> 00:32:14,480
Speaker 1: So it'd be pretty hard, for example, to have like

697
00:32:14,520 --> 00:32:17,400
Speaker 1: a zoom session across the whole planet if you're living

698
00:32:17,440 --> 00:32:18,360
Speaker 1: inside a black hole.

699
00:32:18,680 --> 00:32:19,560
Speaker 2: Oh, thank goodness.

700
00:32:20,800 --> 00:32:24,440
Speaker 1: Great, there's your superpower. You can say no to all

701
00:32:24,480 --> 00:32:25,440
Speaker 1: online meetings.

702
00:32:25,920 --> 00:32:29,760
Speaker 2: That's right, it'd be infinitely boring, just like a regular

703
00:32:30,120 --> 00:32:32,840
Speaker 2: zoom meeting. All right. Well, to answer Ida's question, it

704
00:32:32,840 --> 00:32:36,160
Speaker 2: sounds like she wouldn't gain any special powers except the

705
00:32:36,200 --> 00:32:39,080
Speaker 2: ability to see the rest of the universe in fast.

706
00:32:38,760 --> 00:32:40,560
Speaker 1: Forward and to never have to clean your room.

707
00:32:40,760 --> 00:32:43,240
Speaker 2: Although I think if Ida ever makes it inside of

708
00:32:43,280 --> 00:32:45,360
Speaker 2: a black hole and lists to tell about it, I

709
00:32:45,400 --> 00:32:48,520
Speaker 2: think she would be a superhero in my book. All right.

710
00:32:48,520 --> 00:32:51,760
Speaker 2: Our last question comes from Joey. What are the newest

711
00:32:51,800 --> 00:32:55,360
Speaker 2: and the oldest black holes in the universe? What are

712
00:32:55,400 --> 00:32:59,520
Speaker 2: the newest and oldest black holes? In the universe. Awesome question,

713
00:32:59,640 --> 00:33:01,520
Speaker 2: A little we knowsy if.

714
00:33:01,440 --> 00:33:04,680
Speaker 1: You ask me, you don't think he deserves to know.

715
00:33:07,440 --> 00:33:10,040
Speaker 2: I'm saying, if you go around asking people's age, you know,

716
00:33:10,120 --> 00:33:11,600
Speaker 2: you might get some curd answers.

717
00:33:13,480 --> 00:33:15,640
Speaker 1: No. I think the biggest, oldest black holes in the

718
00:33:15,720 --> 00:33:18,080
Speaker 1: universe are probably proud of their status. You know, they're

719
00:33:18,080 --> 00:33:21,560
Speaker 1: like silver backs tramping around in the jungles at the

720
00:33:21,600 --> 00:33:22,720
Speaker 1: hearts of galaxies.

721
00:33:23,160 --> 00:33:26,560
Speaker 2: Mmmm. I see, Yeah, they're like the alpha black holes

722
00:33:26,720 --> 00:33:27,280
Speaker 2: that we're.

723
00:33:27,080 --> 00:33:29,440
Speaker 1: Saying, yeah, the ogs exactly.

724
00:33:29,720 --> 00:33:32,719
Speaker 2: All right, Well, this is an interesting question because we

725
00:33:32,840 --> 00:33:36,360
Speaker 2: know that black holes form very early on in the universe,

726
00:33:36,440 --> 00:33:38,640
Speaker 2: and we know that black holes are forming all the

727
00:33:38,640 --> 00:33:41,320
Speaker 2: time right now. So you know, I wonder if his

728
00:33:41,440 --> 00:33:43,800
Speaker 2: question is what are the oldest and newest black holes

729
00:33:43,840 --> 00:33:47,040
Speaker 2: we know about? Or what are the oldest and newest

730
00:33:47,080 --> 00:33:48,960
Speaker 2: black holes that exist in the universe.

731
00:33:49,200 --> 00:33:51,680
Speaker 1: Yeah, right, Both of those are good questions. In the

732
00:33:51,720 --> 00:33:54,000
Speaker 1: case of the oldest black hole, we definitely don't know

733
00:33:54,560 --> 00:33:57,760
Speaker 1: what is the oldest black hole, or theoretically what could

734
00:33:57,800 --> 00:34:00,680
Speaker 1: be the oldest black hole, because there's one theory that

735
00:34:00,720 --> 00:34:04,080
Speaker 1: black holes are as old as the universe itself, that

736
00:34:04,120 --> 00:34:07,280
Speaker 1: they might even like be older than electrons, that black

737
00:34:07,280 --> 00:34:09,720
Speaker 1: holes could have been formed during the Big Bang.

738
00:34:10,160 --> 00:34:14,000
Speaker 2: Whoa wait, even before we had like quantum fields.

739
00:34:13,640 --> 00:34:16,560
Speaker 1: Before we had matter, before those quantum fields settled down,

740
00:34:16,880 --> 00:34:19,640
Speaker 1: so we could have things called electrons and protons and

741
00:34:19,719 --> 00:34:22,680
Speaker 1: quarks when things were still so hot and so dense

742
00:34:22,920 --> 00:34:25,440
Speaker 1: that talking about them in terms of those objects doesn't

743
00:34:25,440 --> 00:34:26,920
Speaker 1: make a lot of sense, the way you wouldn't talk

744
00:34:26,920 --> 00:34:29,080
Speaker 1: about a wave in terms of its drops. So there's

745
00:34:29,120 --> 00:34:32,719
Speaker 1: this theory of primordial black holes that suggest that very

746
00:34:32,760 --> 00:34:35,560
Speaker 1: hot patches of the universe might have collapsed into black

747
00:34:35,560 --> 00:34:38,799
Speaker 1: holes even before matter was formed, and those black holes

748
00:34:38,920 --> 00:34:40,000
Speaker 1: might still be around.

749
00:34:40,360 --> 00:34:43,959
Speaker 2: Mm they wouldn't have evaporated by now or right because

750
00:34:44,000 --> 00:34:45,880
Speaker 2: black holes that don't die very easily.

751
00:34:46,040 --> 00:34:48,440
Speaker 1: Some of the black holes would definitely have evaporated. The

752
00:34:48,440 --> 00:34:51,520
Speaker 1: bigger black holes evaporate more slowly, and smaller black holes

753
00:34:51,560 --> 00:34:53,799
Speaker 1: evaporate quickly, so we would expect it some of them

754
00:34:53,800 --> 00:34:56,200
Speaker 1: to have evaporated and some of them to still be around,

755
00:34:56,239 --> 00:34:59,319
Speaker 1: and some of them to be evaporating right now. So

756
00:34:59,400 --> 00:35:01,600
Speaker 1: if the scenari is true, we should be able to

757
00:35:01,640 --> 00:35:04,760
Speaker 1: see these primordial black holes like evaporating all the time.

758
00:35:05,040 --> 00:35:07,840
Speaker 2: So maybe the oldest black hole in the universe was

759
00:35:07,880 --> 00:35:10,680
Speaker 2: there from the beginning, from the beginning of the universe.

760
00:35:10,920 --> 00:35:13,520
Speaker 1: It's possible. It's even this fun theory that this impact

761
00:35:13,520 --> 00:35:16,719
Speaker 1: inside Burea about one hundred years ago, which mysteriously left

762
00:35:16,719 --> 00:35:20,200
Speaker 1: no crater, was actually a primordial black hole that took

763
00:35:20,239 --> 00:35:22,440
Speaker 1: like a core sample of the Earth instead of an

764
00:35:22,480 --> 00:35:23,560
Speaker 1: actual medior.

765
00:35:23,520 --> 00:35:26,400
Speaker 2: WHOA, Well, we should do an episode about that.

766
00:35:28,280 --> 00:35:30,840
Speaker 1: We should. The problem with primordial black holes is again,

767
00:35:31,000 --> 00:35:33,960
Speaker 1: if they were created, we should see them evaporating all

768
00:35:34,000 --> 00:35:36,239
Speaker 1: the time, and we haven't ever seen one. We've looked

769
00:35:36,239 --> 00:35:39,440
Speaker 1: for evidence of black holes evaporating very bright flashes of

770
00:35:39,440 --> 00:35:42,919
Speaker 1: Hawking radiation, but haven't seen any. So it's a possibility

771
00:35:43,000 --> 00:35:45,840
Speaker 1: that there are black holes as old as the universe,

772
00:35:46,160 --> 00:35:48,640
Speaker 1: but it's still just theoretical. But we have seen some

773
00:35:48,840 --> 00:35:51,600
Speaker 1: very very old black holes, like actually seeing them.

774
00:35:51,800 --> 00:35:54,120
Speaker 2: So then what's the oldest black hole we know about?

775
00:35:54,160 --> 00:35:57,040
Speaker 1: The oldest black hole we've ever seen was formed around

776
00:35:57,080 --> 00:36:00,320
Speaker 1: five hundred million years after the Big Bang. It was

777
00:36:00,360 --> 00:36:03,400
Speaker 1: seen by the games web Space telescope. It's super duper

778
00:36:03,520 --> 00:36:06,160
Speaker 1: far away, which is why we can see so far

779
00:36:06,320 --> 00:36:09,120
Speaker 1: back in time. Remember, light takes time to get here

780
00:36:09,160 --> 00:36:11,200
Speaker 1: and so the further things are, the further we're looking

781
00:36:11,280 --> 00:36:13,560
Speaker 1: back in time. So we're seeing this black hole which

782
00:36:13,600 --> 00:36:16,360
Speaker 1: formed just a few hundred million years after the Big Bang.

783
00:36:16,440 --> 00:36:20,960
Speaker 1: It's called sears ceers one zero one nine.

784
00:36:21,040 --> 00:36:24,040
Speaker 2: Well, what that means that it's like thirteen fourteen billion

785
00:36:24,120 --> 00:36:24,600
Speaker 2: years old.

786
00:36:24,680 --> 00:36:27,960
Speaker 1: That's exactly right. It's between thirteen and fourteen billion years old,

787
00:36:28,000 --> 00:36:30,759
Speaker 1: which is pretty old. At the time the light left it,

788
00:36:30,760 --> 00:36:34,080
Speaker 1: it only had about nine million solar masses, which is

789
00:36:34,160 --> 00:36:36,960
Speaker 1: much smaller than some other super massive black holes which

790
00:36:37,000 --> 00:36:40,000
Speaker 1: have grown to like billions of solar masses. In the meantime,

791
00:36:40,040 --> 00:36:42,520
Speaker 1: of course, it might have grown the light we're seeing

792
00:36:42,560 --> 00:36:43,640
Speaker 1: is very out of date.

793
00:36:43,600 --> 00:36:47,239
Speaker 2: Or it might have disappeared. Right, we don't actually know

794
00:36:47,360 --> 00:36:49,920
Speaker 2: it's the oldest black hole. We just know that it

795
00:36:49,960 --> 00:36:52,120
Speaker 2: was around a long time ago. But by now it

796
00:36:52,160 --> 00:36:55,440
Speaker 2: could have maybe disappeared or evaporated. Isn't it possible?

797
00:36:55,520 --> 00:36:57,800
Speaker 1: It's possible. You're right that we're not getting new information

798
00:36:57,920 --> 00:36:59,920
Speaker 1: about this very quickly. We'd have to waste billions if

799
00:37:00,120 --> 00:37:03,200
Speaker 1: years for the updates. But it's unlikely that a massive

800
00:37:03,200 --> 00:37:05,759
Speaker 1: black hole in a cluster of stars, which is where

801
00:37:05,760 --> 00:37:08,799
Speaker 1: we've seen it, would evaporate into nothing. To evaporate, it

802
00:37:08,840 --> 00:37:11,399
Speaker 1: really has to be isolated to not be fed at all.

803
00:37:11,560 --> 00:37:14,360
Speaker 1: And a black hole with nine million solar masses is

804
00:37:14,400 --> 00:37:17,160
Speaker 1: going to have very very faint Hawking radiation. The Hawking

805
00:37:17,239 --> 00:37:20,319
Speaker 1: radiation goes like inversely proportional to the mass, so very

806
00:37:20,320 --> 00:37:23,479
Speaker 1: low mass black holes evaporate more quickly than very high

807
00:37:23,480 --> 00:37:24,360
Speaker 1: mass black holes.

808
00:37:25,160 --> 00:37:27,040
Speaker 2: What if Ida went into that one and.

809
00:37:27,000 --> 00:37:30,200
Speaker 1: Broke it up, that would be a superpower.

810
00:37:30,320 --> 00:37:32,840
Speaker 2: Yeah, maybe that Maybe she didn't get superpowers when she

811
00:37:32,920 --> 00:37:35,600
Speaker 2: went in. All right, So that's the oldest black hole

812
00:37:35,680 --> 00:37:38,279
Speaker 2: we know about. What are the youngest black holes we

813
00:37:38,280 --> 00:37:38,680
Speaker 2: know about?

814
00:37:38,800 --> 00:37:40,920
Speaker 1: The youngest black hole in the universe is certainly one

815
00:37:40,920 --> 00:37:43,480
Speaker 1: that was created right now, and then another one created

816
00:37:43,560 --> 00:37:45,920
Speaker 1: right now. I mean, they're happening all the time. We

817
00:37:46,000 --> 00:37:49,280
Speaker 1: know that supernovas, which are typical precursors for black holes,

818
00:37:49,480 --> 00:37:52,520
Speaker 1: happen like every fifty years in our galaxy. But you know,

819
00:37:52,560 --> 00:37:55,520
Speaker 1: there's trillions of galaxies out there, so there's almost certainly

820
00:37:55,560 --> 00:37:58,080
Speaker 1: a black hole being formed as we speak. And by

821
00:37:58,160 --> 00:37:59,840
Speaker 1: the time you listen to this podcast that will be

822
00:37:59,800 --> 00:38:02,080
Speaker 1: out date, the'll be a new black hole formed that's

823
00:38:02,120 --> 00:38:04,719
Speaker 1: even more recent. So the youngest black hole in the

824
00:38:04,840 --> 00:38:07,480
Speaker 1: universe is definitely one that was just formed.

825
00:38:07,640 --> 00:38:11,360
Speaker 2: They're probably forming all the time right now, right, especially

826
00:38:11,360 --> 00:38:14,200
Speaker 2: if it's an infinite universe, there's an infinite number of

827
00:38:14,239 --> 00:38:15,560
Speaker 2: black holes being born right now.

828
00:38:15,640 --> 00:38:17,960
Speaker 1: Yeah, that's exactly right. So the youngest black hole is

829
00:38:18,000 --> 00:38:20,879
Speaker 1: constantly being replaced by some new baby black hole.

830
00:38:21,080 --> 00:38:23,080
Speaker 2: But what about the youngest one we know about?

831
00:38:23,239 --> 00:38:25,600
Speaker 1: So the youngest black hole that we have seen is

832
00:38:25,640 --> 00:38:29,600
Speaker 1: called W forty nine B. It's about twenty six thousand

833
00:38:29,680 --> 00:38:31,919
Speaker 1: light years away from Earth, and we know it's about

834
00:38:31,960 --> 00:38:34,920
Speaker 1: twenty seven thousand years old because the light from it

835
00:38:35,000 --> 00:38:37,440
Speaker 1: indicates that what we're seeing is a black hole that's

836
00:38:37,440 --> 00:38:39,839
Speaker 1: about a thousand years old. So we're looking at the

837
00:38:39,880 --> 00:38:42,880
Speaker 1: remnants of a supernova collapse that formed a black hole

838
00:38:43,200 --> 00:38:46,440
Speaker 1: about twenty seven thousand years ago twenty six thousand light

839
00:38:46,520 --> 00:38:49,319
Speaker 1: years away. So to us, it looks a thousand years old.

840
00:38:49,600 --> 00:38:51,320
Speaker 2: But wait, wait, wait, how do we know it's age.

841
00:38:51,360 --> 00:38:53,200
Speaker 2: We can tell it's aged from the light we get

842
00:38:53,200 --> 00:38:55,800
Speaker 2: from it, or we just saw the supernova and assume

843
00:38:55,920 --> 00:38:57,560
Speaker 2: that a black hole formed inside of it.

844
00:38:57,719 --> 00:39:00,319
Speaker 1: Yeah, great question this one. We can actually do the

845
00:39:00,360 --> 00:39:02,920
Speaker 1: history of it just by running the clock backwards. We

846
00:39:02,960 --> 00:39:05,960
Speaker 1: look at the distribution of iron and sulfur and silicon

847
00:39:06,200 --> 00:39:08,560
Speaker 1: in the remnant, and we can tell what happened and

848
00:39:08,640 --> 00:39:11,040
Speaker 1: how long it's been drifting. So we can run our

849
00:39:11,040 --> 00:39:13,640
Speaker 1: clock backwards essentially and say, oh, this is about a

850
00:39:13,680 --> 00:39:15,640
Speaker 1: thousand years old, the same way you could look at

851
00:39:15,640 --> 00:39:18,040
Speaker 1: a mushroom cloud from a nuclear bomb. You could tell

852
00:39:18,080 --> 00:39:19,200
Speaker 1: when it went off.

853
00:39:19,480 --> 00:39:22,080
Speaker 2: And you can actually see the black hole in the middle. Like,

854
00:39:22,440 --> 00:39:24,120
Speaker 2: but I thought we could only see black holes if

855
00:39:24,160 --> 00:39:26,640
Speaker 2: there was like if it was like a quasar or something.

856
00:39:26,880 --> 00:39:28,960
Speaker 1: Yeah, you're right. We can't see the black hole directly

857
00:39:29,000 --> 00:39:32,080
Speaker 1: because the black hole is black. We're deducing the presence

858
00:39:32,080 --> 00:39:34,160
Speaker 1: of the black hole from the mass of the whole

859
00:39:34,200 --> 00:39:36,840
Speaker 1: system and the X rays from the hot gas that

860
00:39:36,840 --> 00:39:40,080
Speaker 1: are nearby. And so according to our model, a black

861
00:39:40,120 --> 00:39:43,200
Speaker 1: hole has formed. Like what we're seeing is consistent with

862
00:39:43,280 --> 00:39:46,240
Speaker 1: a star that exploded and left behind a black hole.

863
00:39:46,400 --> 00:39:48,480
Speaker 2: All right, So then the youngest black hole that we

864
00:39:48,640 --> 00:39:51,799
Speaker 2: think we know about is about one thousand years old.

865
00:39:51,960 --> 00:39:53,600
Speaker 1: It looks a thousand years old to us, but it

866
00:39:53,640 --> 00:39:55,480
Speaker 1: happened twenty seven thousand years ago.

867
00:39:55,960 --> 00:39:57,840
Speaker 2: Mm. I mean we caught it, like we took a

868
00:39:57,840 --> 00:40:00,360
Speaker 2: picture of it when it was a thousand years old,

869
00:40:00,400 --> 00:40:03,759
Speaker 2: but the picture was taken twenty six thousand years ago exactly.

870
00:40:03,840 --> 00:40:06,160
Speaker 1: And to answer your other question, like, it's possible that

871
00:40:06,200 --> 00:40:09,120
Speaker 1: we did see this thing go supernova that like Chinese

872
00:40:09,200 --> 00:40:11,360
Speaker 1: astronomers a thousand years ago, we're looking up at the

873
00:40:11,400 --> 00:40:13,839
Speaker 1: sky and side. We do have some examples of that

874
00:40:13,880 --> 00:40:16,560
Speaker 1: where we see a supernova remnant, and we can find

875
00:40:16,680 --> 00:40:20,640
Speaker 1: in the historical record Chinese or Persian or Indian astronomers

876
00:40:20,640 --> 00:40:23,360
Speaker 1: writing about that supernova, which is pretty cool. Not in

877
00:40:23,360 --> 00:40:25,839
Speaker 1: this case, but it's possible that humans did see this

878
00:40:25,880 --> 00:40:27,439
Speaker 1: one blow up a thousand years ago.

879
00:40:27,760 --> 00:40:31,239
Speaker 2: Whoa do you think kids ask questions about it back then?

880
00:40:31,719 --> 00:40:34,080
Speaker 1: It's been a great, big universe for a great long time,

881
00:40:34,160 --> 00:40:35,440
Speaker 1: so yeah, probably.

882
00:40:37,040 --> 00:40:39,080
Speaker 2: All right, Well, I think that answer is Joey's question.

883
00:40:39,320 --> 00:40:41,560
Speaker 2: Those black holes in the universe might be the ones

884
00:40:41,600 --> 00:40:44,279
Speaker 2: that were formed with the universe, but we don't know

885
00:40:44,400 --> 00:40:47,880
Speaker 2: for sure. There is one that's at least thirteen to

886
00:40:47,920 --> 00:40:50,160
Speaker 2: fourteen billion years old that we know about, and there's

887
00:40:50,200 --> 00:40:53,000
Speaker 2: one that was born about twenty seven thousand years ago

888
00:40:53,360 --> 00:40:55,200
Speaker 2: that is the youngest one we know about. Although there

889
00:40:55,200 --> 00:40:58,160
Speaker 2: are probably definitely black holes being born all the time

890
00:40:58,239 --> 00:40:59,000
Speaker 2: right now, and.

891
00:40:58,960 --> 00:41:01,240
Speaker 1: I hope that one of those blacks is being formed

892
00:41:01,360 --> 00:41:05,400
Speaker 1: near some distant human civilization that's inspiring them to invent

893
00:41:05,560 --> 00:41:06,959
Speaker 1: faster than light travel.

894
00:41:06,800 --> 00:41:11,200
Speaker 2: And maybe better cleaning technology, because we could all use that.

895
00:41:11,320 --> 00:41:13,920
Speaker 1: And maybe give Ida special powers so that our corner

896
00:41:13,960 --> 00:41:16,720
Speaker 1: of the universe becomes less boring and we get more visitors.

897
00:41:16,840 --> 00:41:18,279
Speaker 2: I think if you take all of these kids and

898
00:41:18,280 --> 00:41:20,040
Speaker 2: put them into a team together to be like a

899
00:41:20,080 --> 00:41:23,440
Speaker 2: superhero physics team. I mean, these kids are so curious

900
00:41:23,560 --> 00:41:24,480
Speaker 2: and clever and smart.

901
00:41:24,600 --> 00:41:26,399
Speaker 1: Yeah, well, I hope that they and all the kids

902
00:41:26,400 --> 00:41:29,320
Speaker 1: inspired by your book do solve some of our problems

903
00:41:29,320 --> 00:41:31,560
Speaker 1: and change the way we understand the universe.

904
00:41:31,800 --> 00:41:34,840
Speaker 2: So thanks again to all of our kid question askers

905
00:41:35,040 --> 00:41:37,680
Speaker 2: and to all of our listeners for sending in their questions.

906
00:41:37,920 --> 00:41:39,719
Speaker 1: That's right, what's that website? One more time?

907
00:41:40,000 --> 00:41:43,200
Speaker 2: Great Big Universe dot Net. We hope you enjoyed that.

908
00:41:43,920 --> 00:41:46,359
Speaker 2: Thanks for joining us, See you next time.

909
00:41:54,120 --> 00:41:56,920
Speaker 1: Thanks for listening, and remember that. Daniel and Jorge Explain

910
00:41:56,960 --> 00:42:01,879
Speaker 1: the Universe is a production of iHeartRadio. More podcast from iHeartRadio,

911
00:42:02,000 --> 00:42:06,200
Speaker 1: visit the iHeartRadio app, Apple Podcasts, or wherever you listen

912
00:42:06,280 --> 00:42:07,400
Speaker 1: to your favorite shows,