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Speaker 1: Are black holes actually black? Is life always built on

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Speaker 1: a carbon stack?

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Speaker 2: Can one star make another explode? What happens if you

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Speaker 2: lick an electrode?

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Speaker 1: Would biology beat physics in a fair fight? Why is

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Speaker 1: dark chocolate better than white?

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Speaker 2: Hawking predicted that black holes glow? What makes a supernova blow?

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Speaker 1: Biology, physics, archaeology, forestry, really anything other than chemistry?

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Speaker 2: What diseases do you get from your cat? Well, we'll

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Speaker 2: find the answers to all that.

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Speaker 1: Whatever questions keep you up at night, Daniel and Kelly's

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Speaker 1: answer will make it right. Welcome to another Listener Questions

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Speaker 1: episode on Daniel and Kelly's Extraordinary Universe. Hello, Kelly Weener

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Speaker 1: Spin I'm a parasitologist, and today we're talking about chemistry.

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Speaker 2: Hi, I'm Daniel. I'm a particle physicist because I don't

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Speaker 2: like chemistry. So what am I even doing here today?

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Speaker 1: Well, so, Daniel, my question for you today is why

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Speaker 1: is chemistry the worst science?

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Speaker 2: How much time do you have, Kelly.

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Speaker 1: I've did, We've got an hour.

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Speaker 2: No, chemistry is amazing because it's the closest thing we

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Speaker 2: have to explaining magic, like the things that you can

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Speaker 2: see happen with your own eyes. You know, seeing a

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Speaker 2: solid turn into a liquid turn into a gas is

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Speaker 2: kind of incredible, and the fact that we can take

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Speaker 2: that apart and understand it microscopically is amazing. And it's

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Speaker 2: so much more concrete than particle physics or even astrophysics sometimes.

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Speaker 2: So I have a lot of respect for the relevance

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Speaker 2: of chemistry, but I really struggle with the complexity of it,

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Speaker 2: Like there's so many different rules to apply in different

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Speaker 2: situations and a weeks to remember all the exceptions, and

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Speaker 2: this electron and that electron, and it doesn't have the

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Speaker 2: simplicity that I like in particle physics. But you know, hey,

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Speaker 2: that's purely a subjective preference, right, And I'm really glad

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Speaker 2: that there's different kinds of science for different kinds of folks,

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Speaker 2: so we get all the fun different kinds of sciences

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Speaker 2: happening here on our planet.

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Speaker 1: Yeah, no, I agree, and I'm joking. My senior honors

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Speaker 1: research project was in organic chemistry. I'm minored in chemistry,

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Speaker 1: but man, it was hard taking oakem over the summer

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Speaker 1: because I'm not good at visualizing things in three D

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Speaker 1: and seeing those reactions happen in my head is really hard.

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Speaker 1: But I got lucky, so I took it over the summer,

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Speaker 1: and it was like four hours of lecture and then

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Speaker 1: two hours of lab like every day of the week.

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Speaker 1: It was intense. I had a group of friends. I

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Speaker 1: was one of six, and we called ourselves the Benzene

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Speaker 1: Ring because there's six carbons and a benzene ring.

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Speaker 2: I got a chemistry joke look at that.

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Speaker 1: And we would pull all nighters on Thursday nights to

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Speaker 1: study for the Friday exams. And I will always think

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Speaker 1: fondly of those people who got me through like the

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Speaker 1: hardest summer of my life. But anyway, I like it.

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Speaker 1: I just find it way harder than just about anything

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Speaker 1: else I have to think of. But you know, I

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Speaker 1: take a lot of medications that I'm sure would not

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Speaker 1: be around but for the miracle of chemistry.

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Speaker 2: Exactly. I'm ever so grateful for chemistry. And though I

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Speaker 2: take every opportunity to make fun of chemistry, I also

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Speaker 2: want to make sure people out there understand that I

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Speaker 2: have a lot of respect for it, of course as

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Speaker 2: a science. And I will say that there are a

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Speaker 2: few listeners who are chemistry professors who write in and say,

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Speaker 2: don't worry keep joking about chemistry.

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Speaker 1: It makes me laugh so good. Yes, I joke about

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Speaker 1: it the same way I joke about a sibling, where

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Speaker 1: it's like you love them, you're picking fun at them.

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Speaker 1: If somebody else does it, you get a little defensive.

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Speaker 1: But yes, no, I love chemistry. It's just man, My

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Speaker 1: brain was not made for chemistry, but I'm so glad

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Speaker 1: other people's brains are.

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Speaker 2: And chemistry, like all kinds of science, inspire people to

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Speaker 2: ask questions, to wonder like how does this work? How

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Speaker 2: does this fit together? What are the rules for this?

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Speaker 2: And if you have questions about physics, or biology or

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Speaker 2: even chemistry, please write to us and ask your questions.

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Speaker 2: We would love to dig into it to understand the

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Speaker 2: benzene rings and everything else about the universe.

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Speaker 1: Well, bring another expert on to explain.

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Speaker 2: That, And today on the podcast we'll be doing just that,

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Speaker 2: answering questions from listeners. We have a lot of fun questions,

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Speaker 2: including questions about chain reactions in space, which is sort

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Speaker 2: of like superspace chemistry, a question about the chemistry of life,

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Speaker 2: and a question about what it all means and how

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Speaker 2: we know when to accept a scientific theory.

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Speaker 1: An amazing set of questions. Let's get started by hearing

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Speaker 1: what Tim wanted to know about.

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Speaker 3: I was just listening to your podcast about the brightest

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Speaker 3: thing ever seen in the universe, and it got me thinking,

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Speaker 3: is there's such a thing as an event where maybe

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Speaker 3: a chain reaction explosion in space? Maybe it's a binary

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Speaker 3: system supernova, would the other stargo nova as well? Or

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Speaker 3: instead of maybe just disintegrating planets, is it possible for

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Speaker 3: like the core of a planet to heat up so

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Speaker 3: that it explodes. Just piqued by curiosity and thought I'd

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Speaker 3: ask the question.

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Speaker 1: Thanks, WHOA all right? So I could imagine like looking

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Speaker 1: out at the stars at night and seeing like things

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Speaker 1: starting to explode in a chain reaction, and being like

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Speaker 1: I should have put my kids to bed before this

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Speaker 1: happened so they couldn't see it.

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Speaker 4: Yeah.

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Speaker 2: I was wondering what inspired this question. Maybe Tim was

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Speaker 2: worried that, like, if something goes wrong in one star

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Speaker 2: and ends cataclysmically, if you could set off a chain

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Speaker 2: reaction that like destroys the whole universe or something, or

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Speaker 2: if we're safe because every star is so far from

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Speaker 2: the other stars that their fates are all independent.

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Speaker 1: Sounds like Tim and I would have a good time

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Speaker 1: catastrophizing together out of Friday Night.

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Speaker 2: But it's a great question because it makes us think

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Speaker 2: about the relationship between one star and another and also

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Speaker 2: what it takes to like send a star to explode

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Speaker 2: or to disintegrate a planet. It is a fun question.

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Speaker 2: It sort of thinks about the whole universe as if

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Speaker 2: there were elements of a chemical reaction.

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Speaker 1: Right, that's true. But let's start with what's happening inside

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Speaker 1: of one star, and then we'll scale up to multiple stars.

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Speaker 1: You do have chain reactions happening in each star, right,

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Speaker 1: that's right.

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Speaker 2: Yeah, And a chain reaction essentially is a reaction which

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Speaker 2: sets the stage for itself, you know, which makes it

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Speaker 2: more likely for it to happen. And so like a

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Speaker 2: fire is a chain reaction because the combustion produces heat,

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Speaker 2: and that heat triggers more combustion, and so there's a

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Speaker 2: loop there, right, or a chain where one's link leads

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Speaker 2: to the next link. And as you say, inside a

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Speaker 2: star is a sort of a chain reaction because we

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Speaker 2: have fusion happening inside a star. You have gravity squeezing

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Speaker 2: this hot ball of hydrogen and maybe a little bit

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Speaker 2: of helium together, and it creates the conditions necessary for fusion,

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Speaker 2: heat and density, and then fusion itself produces more heat

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Speaker 2: and that increases the chances of fusion. The odds of

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Speaker 2: getting fusion grow very steeply with temperature. So the hotter

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Speaker 2: it is, you mean, the faster those particles are whizzing around,

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Speaker 2: the more likely you are to have fusion. So heat

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Speaker 2: makes fusion more possible.

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Speaker 1: Now we have to get to the really exciting part,

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Speaker 1: which is the explosions are explosions the results of all

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Speaker 1: of the fusion getting out of control. No, when do

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Speaker 1: we get the explosions?

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Speaker 4: Yeah?

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Speaker 2: Essentially you can think of a star during its normal lifetime,

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Speaker 2: during the millions or billions of years that it's burning

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Speaker 2: stably before it explodes, as in something of a balance.

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Speaker 4: Right.

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Speaker 2: You have gravity squeezing in, right, making things hot and dense,

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Speaker 2: and what it would like to do if it wasn't constrained,

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Speaker 2: is turned that into a black hole. Right. Gravity is

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Speaker 2: always just pushing and pushing and pushing, and if there's

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Speaker 2: nothing else but gravity, everything would collapse into a black hole.

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Speaker 2: But in the star you have lots of forces resisting gravity,

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Speaker 2: and when the star is burning, the primary force at

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Speaker 2: the frontier resistant gravity is fusion itself, which is pushing

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Speaker 2: out with radiation, right it produces all this heat, this energy,

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Speaker 2: it's pushing the star out. So fusion is pushing the

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Speaker 2: star out. Gravity is pushing the star back in, and

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Speaker 2: there's a balance there, and if you upset that balance,

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Speaker 2: then yes, the star can go kaboom. And there's basically

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Speaker 2: two ways for the star to go supernova. There's the

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Speaker 2: core collapse supernova and then there's the special fancy type

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Speaker 2: one A supernova, and the core collapse is the one

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Speaker 2: that we mostly think about. This is like the sort

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Speaker 2: of vanilla supernova. What happens is the fusion is doing

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Speaker 2: its job. It's turning hydrogen into helium, and then if

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Speaker 2: it's hot enough, it's turning helium into carbon, and if

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Speaker 2: it's hot enough, it's turning that carbon into neon and

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Speaker 2: oxygen and all sorts of heavier stuff all the way

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Speaker 2: up to iron. But fusing those heavier elements requires more temperature,

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Speaker 2: so a star might not be hot enough to fuse

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Speaker 2: a certain element. For example, right now, our star confuse hydrogen,

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Speaker 2: but it can't fuse helium. So what happens to the

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Speaker 2: helium or the core of our star it just sits

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Speaker 2: there and kind of gets in the way. It's like ash,

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Speaker 2: it's like the product of a fire. And if you

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Speaker 2: have too much of that without climbing over that temperature

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Speaker 2: threshold where you can burn it, also it starts to

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Speaker 2: put the fire out. So smaller stars reach their hotest

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Speaker 2: temperature and can't burn something. So, for example, our star

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Speaker 2: can't burn helium. If the star was larger, it would

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Speaker 2: get hotter at its core and it would burn a

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Speaker 2: heavier element, or a heavier element, or an even heavier

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Speaker 2: element all the way up to iron. When you get

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Speaker 2: up to iron, no star can burn iron and produce

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Speaker 2: energy because when you fuse iron together, it actually costs energy.

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Speaker 2: It cools the star. So the short version of the

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Speaker 2: story is, at some point you've done so much fusion

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Speaker 2: and you've made something that you can no longer burn

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Speaker 2: that's interfering with your fusion, and so fusion is failing

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Speaker 2: and gravity starts to win, and the star starts to

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Speaker 2: collapse because remember the reason it wasn't collapsing was fusion

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Speaker 2: pushing out against gravity, and now you've knocked out those supports,

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Speaker 2: gravity wins, the star implodes, and that implosion then triggers

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Speaker 2: a moment when the star is hot enough to do

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Speaker 2: stuff like burn iron and make super heavy elements, and

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Speaker 2: that triggers the explosion, which is the supernova. So the

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Speaker 2: core collapse supernova comes when the core is not hot

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Speaker 2: enough to burn the ash that's left over, which then

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Speaker 2: triggers the collapse and then an explosion.

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Speaker 1: That was a great explanation. Okay, so you said our

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Speaker 1: sun is not hot enough to make iron, so we've

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Speaker 1: got a bunch of helium. Does it matter what form

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Speaker 1: the ash takes, they all explode no matter what kind

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Speaker 1: of ash is made, or do you get a different

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Speaker 1: result if the ash is helium versus if the ash

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Speaker 1: gets to the iron fase.

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Speaker 2: Yes, So not every star is going to go supernova, Like,

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Speaker 2: for example, our star is not going to go supernova.

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Speaker 2: It's not big enough. It's going to accumulate a lot

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Speaker 2: of helium in its core, and then near the very

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Speaker 2: end it's gonna have a brief moment like maybe minutes

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Speaker 2: in the billions year long life cycle of the star

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Speaker 2: where it can burn that helium and a helium flash

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Speaker 2: and make a little bit of heavier stuff, but it

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Speaker 2: doesn't have enough gravity to actually collapse. Fusion is gonna

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Speaker 2: happen in the outer layers because the core is going

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Speaker 2: to be cold helium, and then you're gonna have this

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Speaker 2: helium flash and it's gonna blow off those outer layers

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Speaker 2: and you're gonna be left with a white dwarf, which

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Speaker 2: is just a hot blob of stuff. It's not fusing anymore.

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Speaker 2: It's just like a big rock sitting there in space glowing,

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Speaker 2: just a white dwarf. If it were bigger, then it

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Speaker 2: would have enough gravity to actually collapse and cause a supernova.

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Speaker 2: So our star is not going to become a supernova

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Speaker 2: unless there is a route for white dwarfs to become supernova's.

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Speaker 2: White dwarfs are just hot stuff sitting there in space,

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Speaker 2: not fusing. Gravity's trying to squeeze them, but it's resisting

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Speaker 2: because of the chemical strength of the stuff. The same

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Speaker 2: reason why like the Earth doesn't collapse into a black hole.

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Speaker 2: It's got chemical strength supporting it. But if something comes

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Speaker 2: along and pours extra material onto the white dwarf, then

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Speaker 2: it can increase its gravity, and gravity can overcome that

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Speaker 2: strength and cause it to collapse and make a special

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Speaker 2: type one a supernova. This happens if you have a

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Speaker 2: white dwarf that has like a sister star nearby, and

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Speaker 2: it eats some of that sister star and then it

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Speaker 2: gets triggered into a supernova. So that's the second kind

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Speaker 2: of supernova. So our star could eventually have a Type

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Speaker 2: one a supernova, but it's not going to have a

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Speaker 2: core collapse supernova.

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Speaker 1: So already got into part of the answer then for

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Speaker 1: why you don't get chain reactions because some of the

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Speaker 1: stars in between can't explode. They're just not the right kind.

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Speaker 1: They're little, they don't have sisters they can eat. Why

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Speaker 1: do we always get to annibalism. I don't know, we do.

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Speaker 1: And so you can't get the chain reaction because there's

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Speaker 1: a lot of stars, you know, in the line that

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Speaker 1: are just not capable of exploding.

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Speaker 2: Yeah, you need the right kind of star. And so

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Speaker 2: the answer to this question is that it's very unlikely

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Speaker 2: to have lots of chain reactions, but it could be

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Speaker 2: possible if you set up the conditions just perfectly. And

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Speaker 2: I'm a big science fiction reader, and so when I

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Speaker 2: got this question from Tama, was reminded of this snippet

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Speaker 2: from a Laring Niven novel Ring World, And there's a

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Speaker 2: scene where they talk about how in the center of

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Speaker 2: the galaxy the stars are all packed together really really close.

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Speaker 2: One star goes nova, it releases a lot of heat

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Speaker 2: and gamma rays, and that heats of the neighboring stars

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Speaker 2: with then blow and it sets off a chain reaction.

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Speaker 2: So it's super cool idea that you could like have

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Speaker 2: this like set of fireworks going off in the galaxy.

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Speaker 2: In order to make this work, you really need exactly

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Speaker 2: the right conditions, and what he describes in Ring World

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Speaker 2: probably wouldn't happen the way he described it, because adding

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Speaker 2: heat to a star doesn't actually cause it to explode.

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Speaker 2: Remember we talked about core collapse supernova. The reason they

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Speaker 2: collapse is because they're not hot enough. They can no

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Speaker 2: longer do fusion to burn the ash that's at their core.

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Speaker 2: So adding heat to a star actually supports it actually

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Speaker 2: makes it more likely to live longer. It prevents its collapse.

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Speaker 2: It doesn't trigger its collapse. Right, These stars explode because

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Speaker 2: they no longer have fusion happening at their core.

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Speaker 1: Is that true? Even if the ash is iron like

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Speaker 1: the end of the process, even adding more heat won't help.

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Speaker 2: Yeah, exactly, because the process of fusing iron SAPs heat

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Speaker 2: from the core. So you have a bunch of iron

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Speaker 2: there and the stars trying to fuse it, but that

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Speaker 2: fusion process is gobbling the energy instead of creating energy.

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Speaker 2: It's like the opposite of a chain reaction. And if

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Speaker 2: you have an external source of heat that's fueling that,

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Speaker 2: that's providing that energy, then you can sustain the star longer.

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Speaker 2: So a core collapse supernova isn't triggered by external heat

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Speaker 2: like radiation from another star. But the other kind of supernova,

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Speaker 2: the type one A supernova, is triggered externally. Right, you

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Speaker 2: have a white dwarf which otherwise wasn't going to go supernova,

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Speaker 2: and you get a deposition of new material from some

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Speaker 2: neighboring star that does trigger it to go over this

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Speaker 2: threshold and then go supernova. And so I asked a

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Speaker 2: friend of mine, David Vartagnan, he's a scientist who studies

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Speaker 2: supernova's he's a Hubbele Einstein fellow at the Carnegie Observatories,

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Speaker 2: and he said, quote, this may be possible for thermonuclear supernova,

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Speaker 2: which requires some version of runaway nuclear chain reactions on

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Speaker 2: the stellar surface. It's possible to change this if situations

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Speaker 2: are just right. So the idea is that you have

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Speaker 2: like a series of these white dwarfs, and you add

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Speaker 2: material to one of them, it goes supernova and then

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Speaker 2: deposits material on the next nearby white dwarf, which causes

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Speaker 2: that to go supernova. Dot dot dot. You have a

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Speaker 2: chain reaction.

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Speaker 1: Do my kids have anything to worry about?

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Speaker 2: You know, your kids do not have anything to worry about.

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Speaker 2: But if you are designing a universe and you want

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Speaker 2: to see this happen, you might be able to arrange it.

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Speaker 2: So if your kids grow up to be god or

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Speaker 2: masters of their own domain, they could set up a

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Speaker 2: supernova chain reaction if they so desire.

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Speaker 1: Malevolent guns, not the nice ones. Also, d'Artagnan super cool

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Speaker 1: last name, like the polar opposite of Wiersmith. I guess

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Speaker 1: maybe it reminds me of d'Artagnan like the Three Musketeers. Okay,

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Speaker 1: on that note, let's get back in touch with Tim

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Speaker 1: and see if he feels like his question was answered.

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Speaker 2: Answer the awesome question, Tim, hope you like the answer.

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Speaker 3: Oh, thanks for answering my question. Danielle and Kelly, Yeah,

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Speaker 3: you answered it. I'm pretty excited to know that under

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Speaker 3: the right circumstances, it can happen, so that it's possible,

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Speaker 3: But it doesn't sound like we're going to have a

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Speaker 3: spectacular fireworks show up exploding stars in our night sky

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Speaker 3: anytime soon. So glad your kids are safe and thanks

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Speaker 3: to answering my question.

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Speaker 1: All right. So next we have a question from Julian

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Speaker 1: from our discord, Daniel, if somebody wants to play with

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Speaker 1: us on discord, where do they find the link to

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Speaker 1: our discord?

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Speaker 2: Go to our website www dot danieland Kelly dot org

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Speaker 2: and you'll see an invitation there to the discorder. You

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Speaker 2: can come and talk and ask questions and make silly

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Speaker 2: jokes and.

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Speaker 1: Be our friends. All right, So let's listen to a

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Speaker 1: question from a New Zealander.

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Speaker 5: Hi, Daniel and Kelly. I'm Julian from New Zealand, a

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Speaker 5: longtime fan of the pod. What I'm interested in hearing

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Speaker 5: is your opinion on the possibility of non carbon based life.

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Speaker 5: Given the practically infinite size of the universe, it seems

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Speaker 5: to me that we should consider other life chemistries as

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Speaker 5: probable rather than But I'm interested to hear your thoughts

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Speaker 5: on this and whether they would be any practical wife

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Speaker 5: for us to search for barmakers from other platforms. Thanks,

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Speaker 5: and keep up the great work. Bye.

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Speaker 2: I love this kind of question because it takes us

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Speaker 2: like out of the mindset that life on Earth is

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Speaker 2: the only way life can be. So I'm dying to

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Speaker 2: hear your thoughts about this, Kelly.

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Speaker 1: Yeah, well, so I was really excited when I got

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Speaker 1: this question because it had the word life in it,

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Speaker 1: and then as I dug a little farther in, I

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Speaker 1: realized this was a chemistry question, and I remain excited.

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Speaker 1: But here we go. Let's do this, all right. So

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Speaker 1: there's about ninety four naturally occurring elements on the periodic table,

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Speaker 1: but the scaffold for life seems to be made of

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Speaker 1: carbon in every case that we've ever looked at, So

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Speaker 1: why carbon and why not something else?

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Speaker 2: So there's ninety four naturally occurring elements. So you're talking

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Speaker 2: about basically the building blocks of life out there in

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Speaker 2: the universe. But if we're starting on a rocky planet,

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Speaker 2: I guess we're assuming that there's like a good chunk

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Speaker 2: of silica and carbon and this kind of stuff, because

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Speaker 2: that's what you need to make a rocky planet, right, yep,

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Speaker 2: all right, cool?

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Speaker 1: You said that the sun makes everything up to iron.

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Speaker 1: Is that right? Yeah, that's right, So we would expect

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Speaker 1: everything up to iron to be fairly plentiful in the universe,

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Speaker 1: Is that fair to say?

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Speaker 2: Yeah, although there's a fascinating distribution of which elements are

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Speaker 2: more common and which ones are less common, which involves

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Speaker 2: a lot of chemistry, but we'll dig into it one day.

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Speaker 1: So the three criteria to sort of like enter us

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Speaker 1: in here is one abundance. So you wouldn't expect nobellium

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Speaker 1: to be the backbone for life because there's not a

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Speaker 1: lot of it out there, But the more common things,

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Speaker 1: you know, they'd be easier for organic organisms to find

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Speaker 1: and incorporate into their bodies. And so what are some

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Speaker 1: of these common atoms?

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Speaker 2: So the universe is mostly hydrogen, you know, because we

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Speaker 2: started with hydrogen and stars have been making heavier stuff

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Speaker 2: for a while, but we're pretty early on in the

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Speaker 2: history of the universe, So mostly hydrogen. Like seventy four

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Speaker 2: percent of the universe by mass fraction is hydrogen, and

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Speaker 2: then a big chunk of it is helium, So like

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Speaker 2: twenty four percent, which is already like most of the universe,

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Speaker 2: you got seventy four percent plus twenty four percent leaves

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Speaker 2: only two percent of the universe is left. But the

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Speaker 2: next one is kind of a surprise. It's oxygen, right,

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Speaker 2: Oxygen is much more common than anything else that's not

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Speaker 2: hydrogen or helium. And then you got carbon and neon

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Speaker 2: and then iron, so those are the most common building

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Speaker 2: blocks in the universe.

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Speaker 1: Okay, all right, so let's go from there. So all right,

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Speaker 1: so abundance is criteria one. Yeah, so you need stuff

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Speaker 1: that's abundant, so we're not surprised to find out that

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Speaker 1: it's carbon, although carbon, as you're noted, is not as

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Speaker 1: abundant as things like hydrogen, but there's still plenty of

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Speaker 1: it on Earth for example. And then the next criteria

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Speaker 1: is that it needs to be versatile and able to

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Speaker 1: make a lot of complex molecules. So the proteins that

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Speaker 1: we have these are very complex, they fold up in

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Speaker 1: different ways, they're made up of lots of different kinds

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Speaker 1: of elements, and the signaling molecules that bacteria make, like

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Speaker 1: every biological organism has lots and lots of super complex

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Speaker 1: molecules that it uses to carry out all of its

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Speaker 1: various functions. So it's thought that ideally you would end

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Speaker 1: up with atoms that are able to bind with the

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Speaker 1: most stuff. And as we move our way across the

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Speaker 1: periodic table, moving across the columns, when you get to

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Speaker 1: the column that carbon is at the top of the

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Speaker 1: stuff in that column are able to bond with four

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Speaker 1: other things. And the reason for that is that they've

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Speaker 1: got Now we're getting into electron shells, and I totally

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Speaker 1: went down a like mental rabbit hole, being like, oh,

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Speaker 1: but electrons, they're not really like particles. Does it make

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Speaker 1: sense to think of them this way in shells anymore?

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Speaker 1: Because maybe their entire functions and let's not go down

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Speaker 1: that rabbit hole for today, or maybe we should.

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Speaker 2: No, In terms of bonds, I think it's totally reasonable

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Speaker 2: to count the number of electrons because even if electrons

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Speaker 2: are waves or particles or something else alien, they follow

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Speaker 2: the rules of quantum mechanics, which dictate how many you

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Speaker 2: can have in each energy level, and that's what determines

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Speaker 2: the whole structure of the periodic table. Right The reason

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Speaker 2: we put carbon and silicon and germanium and tin and

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Speaker 2: lead in the same column is that they all need

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Speaker 2: four electrons to complete a shell. And if all the

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Speaker 2: electrons are filled in the shell, then the atom doesn't

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Speaker 2: like to interact very much, is very happy. And so

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Speaker 2: carbon and silicon both need four electrons to complete their shell.

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Speaker 2: And so I think you're saying that's why they like

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Speaker 2: to interact with four things.

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Speaker 1: So they can interact with as many as four things,

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Speaker 1: or they can interact with fewer and have like double

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Speaker 1: bonds with one of those things, for example. But their

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Speaker 1: ability to interact with the maximum number of things that

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Speaker 1: you can get interactions with on the periodic table allows

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Speaker 1: them to form these super complicated molecules that are necessary

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Speaker 1: for complex life.

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Speaker 2: So can I ask you a naive chemistry question, like

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Speaker 2: I don't understand why carbon is in this situation where

437
00:21:44,240 --> 00:21:46,840
Speaker 2: it can make the most bonds. Like I get that

438
00:21:46,880 --> 00:21:50,439
Speaker 2: it has four valence electrons out of the octet and

439
00:21:50,480 --> 00:21:53,560
Speaker 2: so it needs four more. But then you got nitrogen,

440
00:21:54,000 --> 00:21:56,440
Speaker 2: it's got five. Why can't they use its five electrons?

441
00:21:56,480 --> 00:21:58,840
Speaker 2: Or you got boron it's only got three. It could

442
00:21:58,840 --> 00:22:01,880
Speaker 2: take five more electrons, So why can nothing make five bonds?

443
00:22:02,440 --> 00:22:07,320
Speaker 1: Well, good start, Okay, Nitrogen tends to bond with three

444
00:22:07,359 --> 00:22:09,920
Speaker 1: other things to fill its aid to get to eat,

445
00:22:10,000 --> 00:22:13,680
Speaker 1: whereas boron tends to donate it's three to other things

446
00:22:13,840 --> 00:22:16,640
Speaker 1: as opposed to bonding with five things. I see.

447
00:22:16,680 --> 00:22:18,680
Speaker 2: So carbon sits right there in the sweet spot out

448
00:22:18,680 --> 00:22:21,000
Speaker 2: of the octet. It's got four so it can make

449
00:22:21,040 --> 00:22:23,080
Speaker 2: four bonds. That's pretty cool.

450
00:22:23,240 --> 00:22:25,080
Speaker 1: Yes, And so it's in the position to be the

451
00:22:25,119 --> 00:22:28,000
Speaker 1: backbone four the most complicated kinds of molecules that you

452
00:22:28,040 --> 00:22:28,360
Speaker 1: can make.

453
00:22:28,640 --> 00:22:30,440
Speaker 2: I have another basic question, which is like why do

454
00:22:30,560 --> 00:22:34,080
Speaker 2: we call life carbon based? Like I get carbon is useful,

455
00:22:34,080 --> 00:22:35,880
Speaker 2: but like, why can't we just have a big mix

456
00:22:35,920 --> 00:22:38,840
Speaker 2: of different kinds of chemistries. Why does carbon have to

457
00:22:38,840 --> 00:22:41,560
Speaker 2: be in everything, in every part of life.

458
00:22:41,880 --> 00:22:43,480
Speaker 1: So I think part of why we end up with

459
00:22:43,520 --> 00:22:46,840
Speaker 1: a lot of carbon as the backbone to a lot

460
00:22:46,840 --> 00:22:50,720
Speaker 1: of this stuff is because carbon not only combined with

461
00:22:50,760 --> 00:22:53,280
Speaker 1: a lot of things, but it also forms really strong bonds,

462
00:22:53,280 --> 00:22:55,400
Speaker 1: so it's stable. The kind of molecules that it makes

463
00:22:55,440 --> 00:22:58,240
Speaker 1: are stable. So, for example, if you moved down the

464
00:22:58,320 --> 00:23:00,520
Speaker 1: column that has carbon to other things that are also

465
00:23:00,600 --> 00:23:05,359
Speaker 1: able to bond for things, silicon can also bond four things,

466
00:23:05,400 --> 00:23:09,399
Speaker 1: but that bonding is happening in an even farther out shell,

467
00:23:10,080 --> 00:23:12,439
Speaker 1: and because it's farther away from the nucleus, the bonds

468
00:23:12,440 --> 00:23:13,719
Speaker 1: that it forms are less strong.

469
00:23:13,920 --> 00:23:17,240
Speaker 2: You're saying that silicon is like carbon in the outermost

470
00:23:17,240 --> 00:23:20,639
Speaker 2: electron orbitals, but it's a more complex, heavier nucleus, so

471
00:23:20,640 --> 00:23:24,120
Speaker 2: it's got more electrons. So this outermost electron orbitals are

472
00:23:24,160 --> 00:23:27,400
Speaker 2: further from the core and they're not as tightly bound,

473
00:23:27,480 --> 00:23:29,280
Speaker 2: and so things are a little more loosey goosey.

474
00:23:29,560 --> 00:23:32,000
Speaker 1: Yeah. So carbon has two shells, an inner shell with

475
00:23:32,040 --> 00:23:34,199
Speaker 1: two electrons and then this outer shell with four and

476
00:23:34,200 --> 00:23:36,600
Speaker 1: then the ability to bond to four other things. And

477
00:23:36,640 --> 00:23:39,760
Speaker 1: then silicon has three shells, and so it's got you

478
00:23:39,880 --> 00:23:41,919
Speaker 1: two in the center, eight the one out from that,

479
00:23:42,080 --> 00:23:43,919
Speaker 1: and then it's got four in the outer one and

480
00:23:43,960 --> 00:23:47,240
Speaker 1: the ability to bind with four other things. But because

481
00:23:47,280 --> 00:23:49,920
Speaker 1: that shell where the binding is happening is farther away

482
00:23:49,960 --> 00:23:54,280
Speaker 1: from the nucleus, the bonds that it produces are weaker.

483
00:23:55,320 --> 00:23:58,520
Speaker 1: And so the thought is that when chemical reactions happen

484
00:23:58,600 --> 00:24:00,639
Speaker 1: a lot of times, what's happening is that one of

485
00:24:00,680 --> 00:24:04,800
Speaker 1: the things that bonds to for example, like a carbon backbone,

486
00:24:05,040 --> 00:24:06,600
Speaker 1: you know, gets sort of like pulled off when a

487
00:24:06,640 --> 00:24:10,359
Speaker 1: reaction happens. And when something gets pulled off, carbon is

488
00:24:10,400 --> 00:24:13,040
Speaker 1: strong enough that the backbone stays together and that molecule

489
00:24:13,040 --> 00:24:16,440
Speaker 1: stays complete. But when you've got silicone as the backbone,

490
00:24:16,520 --> 00:24:21,080
Speaker 1: when something breaks off as part of reaction, that process

491
00:24:21,119 --> 00:24:24,760
Speaker 1: of breaking off could also break the backbone of the silicon.

492
00:24:25,440 --> 00:24:27,800
Speaker 1: And so the idea is that carbon is not only

493
00:24:28,320 --> 00:24:31,399
Speaker 1: something that allows you to make super complex molecules, but

494
00:24:31,400 --> 00:24:34,680
Speaker 1: it's also strong enough to allow reactions to happen. I

495
00:24:34,760 --> 00:24:37,000
Speaker 1: think if you had anything else that was like creating

496
00:24:37,000 --> 00:24:41,280
Speaker 1: the backbone for these complicated molecules, the thought is they

497
00:24:41,280 --> 00:24:43,760
Speaker 1: wouldn't be complex enough or they wouldn't be strong enough

498
00:24:43,800 --> 00:24:44,840
Speaker 1: to survive reactions.

499
00:24:45,480 --> 00:24:48,000
Speaker 2: So you need some sort of backbone to hold things

500
00:24:48,040 --> 00:24:51,119
Speaker 2: together while you have this sort of interaction, these chemistry

501
00:24:51,160 --> 00:24:52,000
Speaker 2: of life happening.

502
00:24:52,200 --> 00:24:54,520
Speaker 1: Yes. Yes, And so through this conversation we've hit on

503
00:24:54,560 --> 00:24:59,119
Speaker 1: the three criteria the abundance, versatility, and complexity, which is

504
00:24:59,160 --> 00:25:03,120
Speaker 1: those bonding sites, and then the stability when reactions are happening.

505
00:25:03,440 --> 00:25:05,119
Speaker 1: So those are the three things that we think are

506
00:25:05,160 --> 00:25:09,080
Speaker 1: most important. We've talked about why silicon is thought to

507
00:25:09,280 --> 00:25:12,359
Speaker 1: maybe not be ideal for these reactions, so you'll often

508
00:25:12,400 --> 00:25:15,040
Speaker 1: hear discussions about like, well, could life be silicon based?

509
00:25:15,560 --> 00:25:17,960
Speaker 1: And one reason we think that's unlikely is because you

510
00:25:18,040 --> 00:25:20,480
Speaker 1: might get a lot more breakdown of chemical structures when

511
00:25:20,520 --> 00:25:24,240
Speaker 1: reactions happen. But another thought, water is really important for

512
00:25:24,280 --> 00:25:27,040
Speaker 1: a lot of biological processes. In fact, when we look

513
00:25:27,080 --> 00:25:28,960
Speaker 1: to see where we think life is in the universe,

514
00:25:29,000 --> 00:25:31,560
Speaker 1: one of the criteria we use is whether or not

515
00:25:31,560 --> 00:25:34,720
Speaker 1: there's water there. Water is a helpful solvent, which means

516
00:25:34,720 --> 00:25:37,879
Speaker 1: it helps move around like nutrients and molecules and stuff

517
00:25:37,920 --> 00:25:43,600
Speaker 1: like that. But when carbon binds with water, you make

518
00:25:43,920 --> 00:25:46,520
Speaker 1: carbon dioxide, which is like a gas that we can

519
00:25:46,520 --> 00:25:50,600
Speaker 1: breathe out. But when silicon binds with water, you make

520
00:25:50,640 --> 00:25:54,479
Speaker 1: silicon dioxide, which is sand. And so it's thought that

521
00:25:54,560 --> 00:25:57,280
Speaker 1: sand is probably not something that's like conducive to the

522
00:25:57,320 --> 00:26:02,480
Speaker 1: creation of life, And so that is another proposed reason

523
00:26:02,520 --> 00:26:04,959
Speaker 1: why we don't see silicon based life forms, although some

524
00:26:05,040 --> 00:26:07,679
Speaker 1: labs have managed to do like directed evolution studies to

525
00:26:07,720 --> 00:26:11,280
Speaker 1: get more silicon into molecules. But I feel like that's

526
00:26:11,400 --> 00:26:15,160
Speaker 1: very different than a molecule as part of a living

527
00:26:15,200 --> 00:26:17,280
Speaker 1: being that has no carbon at all.

528
00:26:17,880 --> 00:26:19,560
Speaker 2: So that all does make sense to me as an

529
00:26:19,600 --> 00:26:22,680
Speaker 2: explanation for like why the kind of life that we

530
00:26:22,880 --> 00:26:28,240
Speaker 2: have needs carbon and why having even silicon wouldn't make

531
00:26:28,280 --> 00:26:31,200
Speaker 2: the kind of life we have possible, But doesn't convince

532
00:26:31,280 --> 00:26:34,200
Speaker 2: me that a totally different kind of life wouldn't be possible.

533
00:26:34,440 --> 00:26:36,320
Speaker 2: I mean, if we sat here before there was any life,

534
00:26:36,359 --> 00:26:39,440
Speaker 2: and we were just like looking at atoms and speculating, like, hey,

535
00:26:39,480 --> 00:26:42,600
Speaker 2: what could be complicated enough to have weird things like

536
00:26:42,680 --> 00:26:44,159
Speaker 2: life arise? I don't know that we would have been

537
00:26:44,160 --> 00:26:47,399
Speaker 2: able to predict like carbon is useful. There's a lot

538
00:26:47,400 --> 00:26:50,000
Speaker 2: of complexity in the universe that we failed to predict.

539
00:26:50,200 --> 00:26:53,679
Speaker 2: So isn't it possible that silicon is complex enough to

540
00:26:53,720 --> 00:26:56,560
Speaker 2: do something else which could be the basis of life,

541
00:26:56,600 --> 00:26:59,639
Speaker 2: even if it's like very different and maybe even pretty sandy?

542
00:27:00,720 --> 00:27:02,480
Speaker 1: Yeah, I think maybe. And also, you know, if you

543
00:27:02,560 --> 00:27:06,199
Speaker 1: move over to nitrogen where you've got three binding sites

544
00:27:06,320 --> 00:27:10,280
Speaker 1: instead of four, it's not immediately obvious to me that

545
00:27:10,720 --> 00:27:14,320
Speaker 1: you couldn't have simple life with a little bit less complexity,

546
00:27:14,320 --> 00:27:16,800
Speaker 1: and that you need four and nitrogen wouldn't be enough.

547
00:27:16,800 --> 00:27:18,920
Speaker 1: And so I did find myself while I was reading

548
00:27:18,920 --> 00:27:21,840
Speaker 1: through these explanations wondering if we are to some extent

549
00:27:22,440 --> 00:27:24,560
Speaker 1: a little bit too constrained in our thinking based on

550
00:27:24,600 --> 00:27:26,919
Speaker 1: the life that we observe here. But you know, on

551
00:27:26,960 --> 00:27:29,440
Speaker 1: the other hand, you know, maybe you would have expected

552
00:27:29,440 --> 00:27:33,040
Speaker 1: to have seen a couple examples of like nitrogenous life

553
00:27:33,440 --> 00:27:34,520
Speaker 1: on this planet.

554
00:27:34,320 --> 00:27:34,760
Speaker 2: Here on Earth.

555
00:27:34,800 --> 00:27:37,080
Speaker 1: You mean, yeah, yeah, here on Earth, but we don't

556
00:27:37,119 --> 00:27:39,640
Speaker 1: see that. Yeah, so I don't know, but different temperature

557
00:27:39,760 --> 00:27:42,920
Speaker 1: or pressure conditions might make nitrogen or silicon based life

558
00:27:42,960 --> 00:27:46,399
Speaker 1: a little bit more likely to exist. But this is

559
00:27:46,440 --> 00:27:49,240
Speaker 1: their current I think best understanding of why it's carbon

560
00:27:49,280 --> 00:27:52,680
Speaker 1: based based on our end of one of life forms

561
00:27:52,680 --> 00:27:54,160
Speaker 1: that happen to have carbon backbones.

562
00:27:54,359 --> 00:27:55,960
Speaker 2: Well, why do you think it is that we have

563
00:27:56,200 --> 00:27:58,760
Speaker 2: one kind of life here on Earth? Like all life

564
00:27:59,200 --> 00:28:02,000
Speaker 2: shares the same basic biochemistry and we think there's probably

565
00:28:02,040 --> 00:28:04,560
Speaker 2: a single common ancestor why don't we live on a

566
00:28:04,600 --> 00:28:09,760
Speaker 2: planet where life arose independently multiple times and coexists. Is

567
00:28:09,760 --> 00:28:11,560
Speaker 2: if for the same reason that we have like one

568
00:28:11,600 --> 00:28:14,440
Speaker 2: species of humans because we kill all the other ones

569
00:28:14,520 --> 00:28:16,919
Speaker 2: and we can't tolerate it, or do you think it

570
00:28:17,040 --> 00:28:17,800
Speaker 2: just arose once?

571
00:28:18,200 --> 00:28:19,119
Speaker 1: I really don't know.

572
00:28:19,280 --> 00:28:21,040
Speaker 2: I need answers, Kelly, I need answers.

573
00:28:21,800 --> 00:28:24,240
Speaker 1: I don't think anyone knows. Calm down, Daniel, You know

574
00:28:24,320 --> 00:28:26,919
Speaker 1: that on this podcast we usually don't have the answers.

575
00:28:26,640 --> 00:28:28,080
Speaker 2: I know, but it's so frustrating.

576
00:28:29,119 --> 00:28:32,040
Speaker 1: It is surprising to me that like in one ocean,

577
00:28:32,119 --> 00:28:34,840
Speaker 1: we didn't end up with, you know, in one puddle

578
00:28:35,320 --> 00:28:37,680
Speaker 1: life arose, and then in another puddle on the other

579
00:28:37,720 --> 00:28:41,160
Speaker 1: side of the planet, life arose, and we still see

580
00:28:41,200 --> 00:28:43,640
Speaker 1: signs of both of those. I don't know. I don't know.

581
00:28:44,120 --> 00:28:45,440
Speaker 1: I'd love to know the answer, but I don't.

582
00:28:45,520 --> 00:28:47,720
Speaker 2: It's so frustrating to only have this one example and

583
00:28:47,760 --> 00:28:50,479
Speaker 2: to not know how to generalize and what's typical and

584
00:28:50,520 --> 00:28:54,160
Speaker 2: what's weird. So it'd be fun to find even just

585
00:28:54,200 --> 00:28:57,479
Speaker 2: one more example of life somewhere else, and maybe on

586
00:28:57,520 --> 00:28:59,520
Speaker 2: that planet there's several different kinds of life and several

587
00:28:59,560 --> 00:29:03,160
Speaker 2: different kinds of chemistries of that life would be amazing.

588
00:29:03,600 --> 00:29:06,040
Speaker 1: That would be absolutely amazing, And it would blow my

589
00:29:06,080 --> 00:29:08,160
Speaker 1: mind if we found, like, for example, bacteria in the

590
00:29:08,240 --> 00:29:11,480
Speaker 1: lava tubes or underground on Mars, and if it ended

591
00:29:11,560 --> 00:29:13,720
Speaker 1: up that that was like an independent evolution of life.

592
00:29:14,240 --> 00:29:17,280
Speaker 1: I feel like that would be the coolest discovery of

593
00:29:17,320 --> 00:29:18,280
Speaker 1: my lifetime for sure.

594
00:29:18,360 --> 00:29:20,760
Speaker 2: Yeah, And I think this is a really healthy way

595
00:29:20,800 --> 00:29:23,440
Speaker 2: to think, Like, let's look at the example we have,

596
00:29:23,560 --> 00:29:26,719
Speaker 2: and let's wonder which of these things might be different.

597
00:29:26,760 --> 00:29:28,640
Speaker 2: It's a good way to like try to think outside

598
00:29:28,680 --> 00:29:30,840
Speaker 2: the box, even though it's really hard for us to

599
00:29:30,880 --> 00:29:32,840
Speaker 2: imagine what else could be out there. And I'm sure

600
00:29:32,960 --> 00:29:36,880
Speaker 2: that we're failing to describe the complexity of non Earth life,

601
00:29:36,880 --> 00:29:38,560
Speaker 2: but at least we're making the effort right where like

602
00:29:38,840 --> 00:29:41,680
Speaker 2: trying to understand what could be outside the box of

603
00:29:41,720 --> 00:29:44,800
Speaker 2: our thinking. How you mentioned briefly how water is super

604
00:29:44,840 --> 00:29:47,240
Speaker 2: important for life on Earth, but then I think you

605
00:29:47,280 --> 00:29:49,560
Speaker 2: said something about how it's maybe not necessary, how you

606
00:29:49,600 --> 00:29:52,640
Speaker 2: could have life without water, what could replace water.

607
00:29:52,960 --> 00:29:56,280
Speaker 1: So there's lakes of liquid ethane and methane on Titan,

608
00:29:56,320 --> 00:29:59,400
Speaker 1: which is a moon of Saturn, and it's possible that

609
00:29:59,440 --> 00:30:01,840
Speaker 1: these could be used as solvents to sort of move

610
00:30:01,960 --> 00:30:05,360
Speaker 1: stuff around a living organism instead of water if you

611
00:30:05,400 --> 00:30:08,280
Speaker 1: don't have water present, And maybe this could create different

612
00:30:08,320 --> 00:30:10,840
Speaker 1: kinds of life forms or create the sort of conditions

613
00:30:10,880 --> 00:30:13,959
Speaker 1: necessary for something else to become the backbone of life

614
00:30:14,240 --> 00:30:16,600
Speaker 1: instead of carbon. But I think we're a little bit

615
00:30:16,920 --> 00:30:20,560
Speaker 1: far away from sending probes out there to deliver samples back.

616
00:30:20,600 --> 00:30:25,160
Speaker 2: But fun NASA, that's right, We're doing as much as

617
00:30:25,200 --> 00:30:27,120
Speaker 2: we can to try to think our way outside the box.

618
00:30:27,160 --> 00:30:29,520
Speaker 2: But really what we got to do is actually climb

619
00:30:29,600 --> 00:30:32,520
Speaker 2: outside the box, go to these crazy places in our

620
00:30:32,560 --> 00:30:36,280
Speaker 2: own backyard where there could be other examples of life

621
00:30:36,560 --> 00:30:39,280
Speaker 2: right there waiting for us to discover them. And the

622
00:30:39,320 --> 00:30:42,480
Speaker 2: crazy thing is that all it does is cost money, right,

623
00:30:42,520 --> 00:30:45,240
Speaker 2: and we spend more money on an aircraft carrier than

624
00:30:45,280 --> 00:30:48,360
Speaker 2: it would cost to discover life on Titan. So let's

625
00:30:48,400 --> 00:30:50,400
Speaker 2: go do it, people, Let's go buy some knowledge.

626
00:30:50,520 --> 00:30:55,240
Speaker 1: That's like a good investment to me to ching. All right, Julian,

627
00:30:55,800 --> 00:31:00,160
Speaker 1: I did my best with the chemistry question, but if

628
00:31:00,200 --> 00:31:02,840
Speaker 1: you don't feel like you've got a sufficient answer, let

629
00:31:02,920 --> 00:31:04,960
Speaker 1: us know, and maybe we'll have to pull in a

630
00:31:05,040 --> 00:31:07,920
Speaker 1: chemist to help us answer this question. But I'm looking

631
00:31:07,960 --> 00:31:09,200
Speaker 1: forward to hearing what you had to.

632
00:31:09,120 --> 00:31:12,280
Speaker 5: Say, Danielle and Kelly fist Off. I was a little

633
00:31:12,280 --> 00:31:14,400
Speaker 5: bit worried that I might get kicked off the Discord

634
00:31:14,480 --> 00:31:18,280
Speaker 5: channel for asking such a chemistry heavy question, but it

635
00:31:18,400 --> 00:31:21,520
Speaker 5: was really inspiring to you guys looking at it and

636
00:31:22,200 --> 00:31:25,320
Speaker 5: tackling a subject where you're not necessarily the most comfortable,

637
00:31:25,360 --> 00:31:28,000
Speaker 5: and so thanks very much, and that does definitely answer

638
00:31:28,000 --> 00:31:57,120
Speaker 5: my question. Thanks again, Yes, bye.

639
00:31:47,000 --> 00:31:49,600
Speaker 1: All right, Now for something a little more philosophical.

640
00:31:50,280 --> 00:31:53,080
Speaker 4: I was listening to your episode about thinking like a physicist.

641
00:31:53,640 --> 00:31:55,280
Speaker 4: It got me thinking about different theories that I've been

642
00:31:55,280 --> 00:31:57,320
Speaker 4: proposed over the last few decades, which led me to

643
00:31:57,360 --> 00:32:01,840
Speaker 4: Hawking radiation. There isn't any observation or experimental data confirm

644
00:32:01,920 --> 00:32:05,520
Speaker 4: Hawking radiation, yet the physics community seems to have accepted it.

645
00:32:06,240 --> 00:32:09,000
Speaker 4: My question is why do some theories get accepted and

646
00:32:09,040 --> 00:32:11,560
Speaker 4: others don't. Please help me figure out where my thought

647
00:32:11,560 --> 00:32:13,560
Speaker 4: process might be wrong. Thank you for all you do.

648
00:32:14,080 --> 00:32:16,959
Speaker 2: All right, great question, Eric, I love this because it

649
00:32:17,040 --> 00:32:20,560
Speaker 2: dives into the process of science itself. Not as much

650
00:32:20,560 --> 00:32:23,280
Speaker 2: as the science questions we're asking, but how as a

651
00:32:23,280 --> 00:32:27,760
Speaker 2: community we decide that something is part of the canon

652
00:32:27,920 --> 00:32:29,920
Speaker 2: or something is not. It's a great question.

653
00:32:30,400 --> 00:32:33,840
Speaker 1: It's a great question. Let's start, though, with what is

654
00:32:33,960 --> 00:32:36,280
Speaker 1: Hawking radiation so we can then, you know, compare other

655
00:32:36,320 --> 00:32:36,920
Speaker 1: theories to it.

656
00:32:37,600 --> 00:32:41,120
Speaker 2: Hawking radiation is an amazing little bit of science. We

657
00:32:41,320 --> 00:32:44,320
Speaker 2: talked in the podcast a lot about the biggest question

658
00:32:44,560 --> 00:32:49,000
Speaker 2: in modern physics is how to reconcile gravity with quantum mechanics.

659
00:32:49,000 --> 00:32:51,200
Speaker 2: Nobody knows how to do it. This program of quantum

660
00:32:51,240 --> 00:32:53,680
Speaker 2: gravity we've talked about string theory, we've talked about post

661
00:32:53,760 --> 00:32:56,880
Speaker 2: quantum gravity, this loop quantum gravity, all sorts of efforts,

662
00:32:56,960 --> 00:32:59,560
Speaker 2: nobody knows how to do it, nobody's had any success.

663
00:33:00,040 --> 00:33:04,880
Speaker 2: Accept Stephen Hawking figured out like one little corner of it.

664
00:33:05,480 --> 00:33:09,160
Speaker 2: He used a really clever mathematical trick to understand what

665
00:33:09,400 --> 00:33:12,960
Speaker 2: happens to quantum fields when they're near a black hole.

666
00:33:13,520 --> 00:33:16,120
Speaker 2: So he doesn't have like the big answer to how

667
00:33:16,120 --> 00:33:20,400
Speaker 2: to unify these things or what is the gravity of particles,

668
00:33:20,960 --> 00:33:23,720
Speaker 2: or to do all the calculations. He just was able

669
00:33:23,720 --> 00:33:26,440
Speaker 2: to figure out what happens to quantum fields when they're

670
00:33:26,520 --> 00:33:30,200
Speaker 2: near a black hole using a really clever little mathematical trick.

671
00:33:30,480 --> 00:33:31,520
Speaker 1: And how did he do that.

672
00:33:33,160 --> 00:33:35,480
Speaker 2: It's totally worth digging into it for a minute because

673
00:33:35,520 --> 00:33:38,479
Speaker 2: the story of Hawking radiation, as it's often told in

674
00:33:38,600 --> 00:33:42,600
Speaker 2: popular science accounts, is pretty much totally wrong and doesn't

675
00:33:42,640 --> 00:33:46,040
Speaker 2: describe what was actually done and what Hawking actually figured out.

676
00:33:46,400 --> 00:33:49,600
Speaker 2: The popular story is a story of what happens to particles.

677
00:33:49,640 --> 00:33:52,360
Speaker 2: Do you have fields near an event horizon and they

678
00:33:52,400 --> 00:33:56,600
Speaker 2: fluctuate and create like a particle antiparticle pair. One particle

679
00:33:56,640 --> 00:33:59,000
Speaker 2: falls into the black hole and the other one doesn't,

680
00:33:59,080 --> 00:34:02,120
Speaker 2: and so escapes and that's your Hawking radiation. And the

681
00:34:02,160 --> 00:34:04,200
Speaker 2: problem with that account is that that's not at all

682
00:34:04,240 --> 00:34:06,800
Speaker 2: what we think happens. We don't know how to describe that.

683
00:34:06,800 --> 00:34:10,560
Speaker 2: That would require understanding like how gravity affects particles and

684
00:34:11,239 --> 00:34:14,799
Speaker 2: are those particles real anyway. Really, what Hawking did was

685
00:34:14,840 --> 00:34:19,000
Speaker 2: he thought about the mathematical solutions to the quantum wave equations,

686
00:34:19,080 --> 00:34:21,399
Speaker 2: like quantum fields have waves in them. Those waves are

687
00:34:21,400 --> 00:34:24,440
Speaker 2: particles or other kinds of ripples, and they slash around

688
00:34:24,520 --> 00:34:27,440
Speaker 2: and they follow rules. Those are wave equations, just like

689
00:34:27,480 --> 00:34:31,000
Speaker 2: the mathematics that describes waves in the ocean or waves

690
00:34:31,040 --> 00:34:34,360
Speaker 2: in traffic. Waves are everywhere, and the equations that describe

691
00:34:34,400 --> 00:34:37,840
Speaker 2: quantum fields are also wave equations. And when you solve

692
00:34:37,880 --> 00:34:40,279
Speaker 2: wave equations, you have to make sure that they line

693
00:34:40,360 --> 00:34:42,239
Speaker 2: up on top of each other and they match what

694
00:34:42,320 --> 00:34:45,040
Speaker 2: you see at boundaries and stuff like this. This is

695
00:34:45,080 --> 00:34:47,879
Speaker 2: how we figure out like reflection and refraction of light,

696
00:34:48,200 --> 00:34:51,200
Speaker 2: all sorts of wave equation stuff. And he figured out

697
00:34:51,200 --> 00:34:54,240
Speaker 2: what happens to those waves if you have a weird

698
00:34:54,320 --> 00:34:57,520
Speaker 2: barrier and event horizon. You add that to your quantum fields.

699
00:34:57,680 --> 00:34:59,840
Speaker 2: And he showed that what happens is you have to

700
00:34:59,840 --> 00:35:03,080
Speaker 2: have have a wave coming out of that event horizon.

701
00:35:03,600 --> 00:35:06,760
Speaker 2: So the short version is that the mathematics of quantum

702
00:35:06,800 --> 00:35:11,239
Speaker 2: fields require some outgoing radiation from an event horizon if

703
00:35:11,280 --> 00:35:13,279
Speaker 2: the quantum fields are ever going to work. So you

704
00:35:13,320 --> 00:35:15,719
Speaker 2: don't have to know what the gravity is for particles,

705
00:35:15,800 --> 00:35:18,600
Speaker 2: or what's happening inside that event horizon, or even why

706
00:35:18,680 --> 00:35:22,239
Speaker 2: you have an event horizon, but very generally, anytime that's

707
00:35:22,239 --> 00:35:24,640
Speaker 2: an event horizon near a quantum field, that's going to

708
00:35:24,640 --> 00:35:28,400
Speaker 2: be outgoing radiation. So that's really what Hawking radiation is.

709
00:35:28,400 --> 00:35:31,080
Speaker 2: That's the prediction. And again we don't have a complete

710
00:35:31,080 --> 00:35:35,160
Speaker 2: description of quantum gravity or understand how gravity affects little particles,

711
00:35:35,760 --> 00:35:38,520
Speaker 2: but he predicts that there's this radiation that comes out

712
00:35:38,560 --> 00:35:41,520
Speaker 2: of event horizons just to make the wave equation work

713
00:35:41,560 --> 00:35:42,560
Speaker 2: for quantum fields.

714
00:35:42,800 --> 00:35:45,560
Speaker 1: Okay, so this is a prediction, but it hasn't been tested.

715
00:35:46,000 --> 00:35:48,399
Speaker 1: So for something that you can't test, you can still

716
00:35:48,400 --> 00:35:50,239
Speaker 1: feel pretty good about it if it predicts a lot

717
00:35:50,280 --> 00:35:53,360
Speaker 1: of other things. So like, how good in general is

718
00:35:53,400 --> 00:35:55,640
Speaker 1: the evidence even if we can't directly test it.

719
00:35:55,680 --> 00:35:58,879
Speaker 2: There's absolutely no evidence for Hawking radiation. Okay, but it's

720
00:35:59,000 --> 00:36:01,840
Speaker 2: very cool because it connects to other kinds of physics.

721
00:36:02,080 --> 00:36:06,320
Speaker 2: It also lets you think about black holes thermodynamically. It

722
00:36:06,440 --> 00:36:09,360
Speaker 2: lets you think about black holes as things that have temperature.

723
00:36:09,840 --> 00:36:12,520
Speaker 2: In our universe, everything that's made out of some kind

724
00:36:12,560 --> 00:36:16,319
Speaker 2: of matter has a temperature and glows. Like the Sun

725
00:36:16,400 --> 00:36:19,520
Speaker 2: obviously glows it's really hot, but the Earth also glows.

726
00:36:19,520 --> 00:36:21,600
Speaker 2: It just glows in a wavelength of light that we

727
00:36:21,680 --> 00:36:25,160
Speaker 2: can't see. Glows in the infrared, and you glow, which

728
00:36:25,200 --> 00:36:28,200
Speaker 2: is why if somebody puts on night vision goggles they

729
00:36:28,200 --> 00:36:30,759
Speaker 2: can see you because they're seeing you in the infrared.

730
00:36:30,800 --> 00:36:33,640
Speaker 2: The light that you glow in, and your temperature determines

731
00:36:33,680 --> 00:36:35,680
Speaker 2: what you glow in. So as you get hotter, you

732
00:36:35,719 --> 00:36:38,760
Speaker 2: glow in higher frequency light, which is why, for example,

733
00:36:38,840 --> 00:36:41,360
Speaker 2: metal when you heat it up, gets red hot and

734
00:36:41,360 --> 00:36:45,160
Speaker 2: then white hot. For example. That's all just black body radiation.

735
00:36:45,360 --> 00:36:48,800
Speaker 2: Everything that has a temperature glows. So now if black

736
00:36:48,840 --> 00:36:52,080
Speaker 2: holes glow, you can describe them as having a temperature,

737
00:36:52,400 --> 00:36:56,279
Speaker 2: which is pretty cool, haha. Thermodynamics joke, and it lets

738
00:36:56,280 --> 00:36:59,840
Speaker 2: you use a whole other branch of mathematics and physics

739
00:37:00,160 --> 00:37:02,200
Speaker 2: we've developed for hundreds of years and apply it to

740
00:37:02,280 --> 00:37:05,160
Speaker 2: black holes and think about their entropy and stuff like this.

741
00:37:05,680 --> 00:37:08,440
Speaker 2: So people have been having a lot of fun using

742
00:37:08,600 --> 00:37:11,000
Speaker 2: black holes as a concept and playing around with the

743
00:37:11,000 --> 00:37:14,360
Speaker 2: mathematics of it. There's absolutely no evidence for hawking radiation

744
00:37:14,800 --> 00:37:18,040
Speaker 2: because if hawking radiation does exist in the universe, black

745
00:37:18,080 --> 00:37:20,919
Speaker 2: holes are too far away and hawking radiation is too

746
00:37:21,000 --> 00:37:24,200
Speaker 2: dim for us to see it. So it's possible that

747
00:37:24,239 --> 00:37:26,920
Speaker 2: black holes are all out there emitting this hawking radiation,

748
00:37:27,440 --> 00:37:29,960
Speaker 2: but we've never seen it, and it's very hard to

749
00:37:30,000 --> 00:37:33,319
Speaker 2: imagine how we could in the near future unless we

750
00:37:33,480 --> 00:37:37,440
Speaker 2: made artificial black holes here on Earth to study their radiation.

751
00:37:38,000 --> 00:37:42,319
Speaker 1: All right, So Stephen Hawking is like the rock star physics.

752
00:37:42,520 --> 00:37:46,719
Speaker 1: A rock star, y'all have like three And so to

753
00:37:46,719 --> 00:37:48,880
Speaker 1: what extent do you think this theory has been like,

754
00:37:48,960 --> 00:37:51,839
Speaker 1: quote unquote accepted because he's a rock star.

755
00:37:52,120 --> 00:37:54,920
Speaker 2: Well, I think this theory helped make him a rock star, right,

756
00:37:54,960 --> 00:37:58,239
Speaker 2: So there's some cause and effect there. But Eric's question

757
00:37:58,320 --> 00:38:00,319
Speaker 2: is a good one, like why do people pick up

758
00:38:00,360 --> 00:38:02,359
Speaker 2: on this theory and run with it and build on

759
00:38:02,400 --> 00:38:04,720
Speaker 2: top of it and other stuff is sort of dismissed.

760
00:38:04,760 --> 00:38:07,800
Speaker 2: You know, we have, like Stephen Wolfram got a theory

761
00:38:07,800 --> 00:38:10,560
Speaker 2: of everything that not very many people are working on

762
00:38:10,880 --> 00:38:14,080
Speaker 2: has become accepted. Lots of fringe theories out there that

763
00:38:14,160 --> 00:38:16,879
Speaker 2: nobody's taking up. You know, you have to remember that,

764
00:38:16,960 --> 00:38:21,359
Speaker 2: like science is not some official institution where things get

765
00:38:21,360 --> 00:38:23,400
Speaker 2: graded and accepted or rejected.

766
00:38:23,680 --> 00:38:24,200
Speaker 1: It's just a.

767
00:38:24,120 --> 00:38:26,879
Speaker 2: Bunch of people, and people work on the things they're

768
00:38:26,920 --> 00:38:30,640
Speaker 2: excited about. And the reason hawking radiation has become kind

769
00:38:30,680 --> 00:38:33,239
Speaker 2: of mainstream is that because it opened the door to

770
00:38:33,600 --> 00:38:37,200
Speaker 2: working on other things. Thinking about black holes as thermodynamic

771
00:38:37,239 --> 00:38:40,640
Speaker 2: objects and calculating their temperature and thinking about information. It

772
00:38:40,800 --> 00:38:42,759
Speaker 2: sort of left things for people to do and to

773
00:38:42,840 --> 00:38:45,279
Speaker 2: work on and to build on top of them. But

774
00:38:45,360 --> 00:38:48,160
Speaker 2: you know, that's just personal judgment. People decided, hey, this

775
00:38:48,239 --> 00:38:50,640
Speaker 2: is fun and interesting, I'm going to go work on this,

776
00:38:51,160 --> 00:38:53,120
Speaker 2: and so people just sort of vote with their feet,

777
00:38:53,400 --> 00:38:56,959
Speaker 2: whereas other ideas that might be more valid or better

778
00:38:57,000 --> 00:39:00,920
Speaker 2: descriptions of nature are not getting as much a because

779
00:39:01,320 --> 00:39:03,920
Speaker 2: maybe there's not an obvious problem to work on, or

780
00:39:03,960 --> 00:39:06,600
Speaker 2: there's nothing to do there, or it just doesn't seem

781
00:39:06,640 --> 00:39:09,600
Speaker 2: as fun. People have a sort of a simplistic view

782
00:39:09,640 --> 00:39:13,080
Speaker 2: of how science works and what is science, and think

783
00:39:13,080 --> 00:39:16,680
Speaker 2: that like science has to be experimentally proven before is accepted,

784
00:39:17,160 --> 00:39:20,520
Speaker 2: but there's no official stamp of accepted science. It's just

785
00:39:20,680 --> 00:39:22,799
Speaker 2: what are people doing, what are people working on, what

786
00:39:22,800 --> 00:39:25,719
Speaker 2: are people thinking about? And so it's possible that we

787
00:39:25,719 --> 00:39:28,279
Speaker 2: could discover that Hawking was totally wrong, or it could

788
00:39:28,320 --> 00:39:31,560
Speaker 2: be that Hawking's ideas lead us to understand quantum gravity

789
00:39:31,560 --> 00:39:33,440
Speaker 2: in some way, or it could be that it's a

790
00:39:33,480 --> 00:39:35,279
Speaker 2: dead end that he was able to figure this one

791
00:39:35,320 --> 00:39:37,480
Speaker 2: thing out, but it doesn't give us an opportunity to

792
00:39:37,480 --> 00:39:38,720
Speaker 2: discover anything else.

793
00:39:39,120 --> 00:39:41,440
Speaker 1: Yeah, So ruminating a little bit more on the human

794
00:39:41,480 --> 00:39:44,400
Speaker 1: side of science. I imagine that when you pick a

795
00:39:44,440 --> 00:39:47,080
Speaker 1: theory that you want to spend your career on, you

796
00:39:47,200 --> 00:39:49,319
Speaker 1: probably want to pick a theory that you think is

797
00:39:49,320 --> 00:39:51,160
Speaker 1: one of the ones that has the highest chance of

798
00:39:51,200 --> 00:39:54,680
Speaker 1: being right. I know that people are okay with working

799
00:39:54,719 --> 00:39:57,120
Speaker 1: on theories and finding out that they're wrong, because that

800
00:39:57,239 --> 00:39:59,600
Speaker 1: is an answer and answers are important. But I think

801
00:39:59,600 --> 00:40:02,000
Speaker 1: that probably you pick the ones you want to be correct.

802
00:40:02,000 --> 00:40:04,640
Speaker 1: But I wonder if when you're picking these ideas, how

803
00:40:04,719 --> 00:40:06,640
Speaker 1: much does it also have to do with what is

804
00:40:06,800 --> 00:40:09,920
Speaker 1: testable and what's not. Like even if you think an

805
00:40:09,920 --> 00:40:12,760
Speaker 1: idea is correct, but you can't really test it directly,

806
00:40:12,800 --> 00:40:14,840
Speaker 1: and maybe that makes it hard to like get grants

807
00:40:14,880 --> 00:40:16,960
Speaker 1: to fund your lab or something like how do you

808
00:40:16,960 --> 00:40:19,839
Speaker 1: think these various human factors sort of all add up?

809
00:40:20,280 --> 00:40:20,480
Speaker 4: Yeah.

810
00:40:20,520 --> 00:40:24,239
Speaker 2: I think in theoretical physics, whether it's immediately testable is

811
00:40:24,280 --> 00:40:27,799
Speaker 2: not always one of the top considerations. I think one

812
00:40:27,800 --> 00:40:30,920
Speaker 2: of the top considerations is can I make progress in

813
00:40:30,960 --> 00:40:34,120
Speaker 2: a reasonable amount of time? Like, personally, as a scientist,

814
00:40:34,200 --> 00:40:37,000
Speaker 2: when I choose projects, I could choose to work on

815
00:40:37,280 --> 00:40:40,000
Speaker 2: really big questions like hey, what came before the Big Bang?

816
00:40:40,239 --> 00:40:42,000
Speaker 2: But I have no way to make progress on that

817
00:40:42,080 --> 00:40:44,800
Speaker 2: in a reasonable amount of time. And as a scientist,

818
00:40:44,840 --> 00:40:46,719
Speaker 2: I have to produce science regularly, so I have to

819
00:40:46,800 --> 00:40:50,040
Speaker 2: choose projects where I can make some progress. And I

820
00:40:50,080 --> 00:40:52,240
Speaker 2: think this is a really important thing for young scientists

821
00:40:52,280 --> 00:40:56,800
Speaker 2: to learn, is to spot opportunities like, hey, here's something

822
00:40:56,880 --> 00:40:58,560
Speaker 2: where if we spend a couple of years on this,

823
00:40:58,640 --> 00:41:01,880
Speaker 2: we could actually learn something given the resources and the

824
00:41:01,880 --> 00:41:05,200
Speaker 2: skills that we have. Right, So it's sort of like

825
00:41:05,320 --> 00:41:08,279
Speaker 2: spotting a business opportunity. Oh, there's a market for this,

826
00:41:08,400 --> 00:41:10,920
Speaker 2: and we know how to do it, so let's jump

827
00:41:10,920 --> 00:41:13,719
Speaker 2: on that. And so in my research, for example, you

828
00:41:13,719 --> 00:41:16,279
Speaker 2: know we use machine learning, we're always like looking for

829
00:41:16,360 --> 00:41:19,320
Speaker 2: ways machine learning can solve problems that weren't solved before,

830
00:41:19,360 --> 00:41:21,960
Speaker 2: but again in a reasonable amount of time. So on

831
00:41:22,000 --> 00:41:24,480
Speaker 2: the theoretical physics side, people looking for problems where they

832
00:41:24,480 --> 00:41:27,759
Speaker 2: can make some progress, where there's an opening, but they're

833
00:41:27,760 --> 00:41:30,400
Speaker 2: not always concerned about like is this immediately going to

834
00:41:30,400 --> 00:41:34,120
Speaker 2: be testable, because science isn't just about experiments, you know.

835
00:41:34,239 --> 00:41:38,040
Speaker 2: Science is a big, complex dance that eventually leads to answers.

836
00:41:38,520 --> 00:41:41,759
Speaker 2: We hear a lot of criticism of string theory, for example, saying, oh,

837
00:41:41,800 --> 00:41:44,319
Speaker 2: it's not science because you can't test it, but you know,

838
00:41:44,400 --> 00:41:47,920
Speaker 2: it's a precursor to testing. Sometimes it takes something fifty years,

839
00:41:47,960 --> 00:41:50,560
Speaker 2: one hundred years before it bubbles up and produces something

840
00:41:50,560 --> 00:41:53,080
Speaker 2: that you can test. Doesn't mean that it wasn't science

841
00:41:53,200 --> 00:41:55,959
Speaker 2: until then that you retroactively go back and say, okay,

842
00:41:55,960 --> 00:41:57,760
Speaker 2: now we can test it. So the last one hundred

843
00:41:57,800 --> 00:42:00,520
Speaker 2: years count to science, whereas if it never to something

844
00:42:00,560 --> 00:42:02,800
Speaker 2: you can test that you say it never was science.

845
00:42:03,040 --> 00:42:04,880
Speaker 2: I think that's a little bit overly simplistic.

846
00:42:05,120 --> 00:42:07,640
Speaker 1: All right, Well, so continuing to think out loud here,

847
00:42:07,680 --> 00:42:09,800
Speaker 1: So you said that you don't work on questions related

848
00:42:09,840 --> 00:42:12,520
Speaker 1: to the Big Bang, because you can't produce science regularly

849
00:42:12,560 --> 00:42:16,319
Speaker 1: by doing that. So how do we get questions to

850
00:42:16,360 --> 00:42:20,000
Speaker 1: these really important problems that take a long time? Is

851
00:42:20,000 --> 00:42:22,440
Speaker 1: our system just not set up to answer those questions?

852
00:42:22,520 --> 00:42:24,440
Speaker 1: Or is it something so you know, for example, Darwin,

853
00:42:25,120 --> 00:42:27,120
Speaker 1: he came up with the idea of natural selection, but

854
00:42:27,200 --> 00:42:30,440
Speaker 1: it was like an idea that was the accumulated result

855
00:42:30,719 --> 00:42:33,680
Speaker 1: of observations that happened over like maybe decades. But he

856
00:42:33,800 --> 00:42:36,680
Speaker 1: was publishing a lot of like mollusk papers along the way,

857
00:42:36,800 --> 00:42:39,719
Speaker 1: or like, you know, observations on other things. So are

858
00:42:39,800 --> 00:42:42,239
Speaker 1: people working on the really big questions but just sort

859
00:42:42,280 --> 00:42:44,839
Speaker 1: of slowly in the background while producing something to keep

860
00:42:44,880 --> 00:42:47,880
Speaker 1: their jobs, or like, is it harder and harder to

861
00:42:47,880 --> 00:42:49,960
Speaker 1: get answers to those big questions that take a long

862
00:42:50,000 --> 00:42:51,880
Speaker 1: time today because of the way our funding system is

863
00:42:51,920 --> 00:42:52,279
Speaker 1: set up.

864
00:42:52,400 --> 00:42:54,719
Speaker 2: Yeah, there are people working on big questions. A great

865
00:42:54,760 --> 00:42:58,800
Speaker 2: example are things we call quantum foundations, like which of

866
00:42:58,840 --> 00:43:02,680
Speaker 2: the quantum mechanical interpretations of reality are real? The Copenhagen interpretation,

867
00:43:02,800 --> 00:43:05,719
Speaker 2: the Many World's interpretation. How do we grapple with all that?

868
00:43:05,920 --> 00:43:08,839
Speaker 2: Everybody thinks that's a big problem. A lot of people

869
00:43:08,920 --> 00:43:11,319
Speaker 2: have no idea how to make progress on it, and

870
00:43:11,440 --> 00:43:13,520
Speaker 2: so it's sort of a bit of a dangerous thing

871
00:43:13,600 --> 00:43:15,840
Speaker 2: to dig into for like a young scientist, because you

872
00:43:15,880 --> 00:43:17,960
Speaker 2: could jump into it, work for a couple of years,

873
00:43:18,040 --> 00:43:19,440
Speaker 2: make no progress, and then what do you have to

874
00:43:19,440 --> 00:43:21,680
Speaker 2: show for yourself. So it's the kind of thing that

875
00:43:21,800 --> 00:43:24,680
Speaker 2: people who are well established with like tangent positions i e.

876
00:43:24,920 --> 00:43:27,759
Speaker 2: Like Sean Carroll can dig into and try to make

877
00:43:27,760 --> 00:43:31,200
Speaker 2: some progress on and everybody understands it's really important, but yeah,

878
00:43:31,200 --> 00:43:33,200
Speaker 2: it's hard to know if you're going to make any progress,

879
00:43:33,239 --> 00:43:35,120
Speaker 2: and so a lot of people don't work on that.

880
00:43:35,600 --> 00:43:38,919
Speaker 2: There are also some places that specifically fund this kind

881
00:43:38,920 --> 00:43:41,200
Speaker 2: of work because they realize, hey, it's really important for

882
00:43:41,239 --> 00:43:44,000
Speaker 2: people to be thinking about these big questions or we're

883
00:43:44,040 --> 00:43:46,560
Speaker 2: never going to make any progress on them. And so

884
00:43:46,920 --> 00:43:50,840
Speaker 2: there's some places that specifically right grants just to support

885
00:43:50,840 --> 00:43:53,319
Speaker 2: that kind of research, but they're pretty few and far

886
00:43:53,320 --> 00:43:56,239
Speaker 2: in between. The bigger picture tendency and science I think

887
00:43:56,360 --> 00:43:59,759
Speaker 2: is towards short term promises. A lot of grants that

888
00:43:59,760 --> 00:44:02,600
Speaker 2: you right require you to know what you're going to

889
00:44:02,719 --> 00:44:05,400
Speaker 2: learn in advance and to have a lot of preliminary

890
00:44:05,440 --> 00:44:08,520
Speaker 2: data because this is arms race and science. You know,

891
00:44:08,600 --> 00:44:10,160
Speaker 2: this lab is already set up to do that. That

892
00:44:10,280 --> 00:44:11,359
Speaker 2: lab is already set up.

893
00:44:11,239 --> 00:44:11,560
Speaker 1: To do that.

894
00:44:12,120 --> 00:44:14,440
Speaker 2: And so a lot of science is more about these

895
00:44:14,480 --> 00:44:16,480
Speaker 2: sort of short term results, which I think is a

896
00:44:16,520 --> 00:44:20,880
Speaker 2: shame because we should be doing science as exploratory research. Say, hey,

897
00:44:20,960 --> 00:44:23,200
Speaker 2: let's see what happens if we give a bunch of

898
00:44:23,239 --> 00:44:26,040
Speaker 2: smart people money and time and see what they figure out.

899
00:44:26,560 --> 00:44:30,200
Speaker 1: Agreed, that's a big complaint of mind for the system.

900
00:44:30,440 --> 00:44:34,520
Speaker 1: All right, Well, have we said everything that we want

901
00:44:34,520 --> 00:44:35,680
Speaker 1: to say about Eric's question?

902
00:44:35,880 --> 00:44:37,440
Speaker 2: I think so. If I had to sum it up,

903
00:44:37,440 --> 00:44:39,479
Speaker 2: I would say to Eric that there is no such

904
00:44:39,520 --> 00:44:42,239
Speaker 2: thing as accepted science or not accepted science. It's just

905
00:44:42,440 --> 00:44:44,800
Speaker 2: the kind of things people are working on right now

906
00:44:45,320 --> 00:44:48,000
Speaker 2: that people are excited about, and it's a personal decision,

907
00:44:48,360 --> 00:44:51,280
Speaker 2: not some like institutional label we put on ideas.

908
00:44:51,520 --> 00:44:54,360
Speaker 1: And let's see what Eric has to say about that answer.

909
00:44:54,960 --> 00:44:57,319
Speaker 4: Hi, Danielle Kelly, this does help me understand better how

910
00:44:57,360 --> 00:44:59,480
Speaker 4: science works. I tend to make the mistake of thinking

911
00:44:59,480 --> 00:45:03,360
Speaker 4: looks science is monolithic with nothing but cold heart facts,

912
00:45:03,480 --> 00:45:06,000
Speaker 4: and I forget that behind the science are human beings.

913
00:45:06,160 --> 00:45:08,880
Speaker 4: My idea of the scientific method comes from high school,

914
00:45:08,920 --> 00:45:12,239
Speaker 4: which took a more simplistic approach. I think it's more

915
00:45:12,280 --> 00:45:14,960
Speaker 4: accurate to say science is more the art of human

916
00:45:15,000 --> 00:45:18,520
Speaker 4: curiosity than just cold, hard facts.

917
00:45:19,480 --> 00:45:20,479
Speaker 3: It is, after all.

918
00:45:20,440 --> 00:45:25,480
Speaker 4: Human beings and all their complexities that ultimately strive to

919
00:45:25,560 --> 00:45:28,600
Speaker 4: unravel the mysteries of the universe through a blend of

920
00:45:28,640 --> 00:45:32,839
Speaker 4: creativity and skepticism, and ultimately, if it is a good

921
00:45:32,840 --> 00:45:37,840
Speaker 4: idea that can stand scrutiny, it will become accepted. Hockey

922
00:45:38,000 --> 00:45:42,920
Speaker 4: radiation is a prime example of this. Thank you, Daniel

923
00:45:42,920 --> 00:45:45,280
Speaker 4: and Kelly for taking the time to help me understand

924
00:45:45,320 --> 00:45:47,920
Speaker 4: the process of science a bit more, and I certainly

925
00:45:47,960 --> 00:45:50,359
Speaker 4: appreciate everything you do. Take care.

926
00:45:57,600 --> 00:46:01,440
Speaker 1: Daniel and Kelly's Extraordinary Universe is produce by iHeartRadio. We

927
00:46:01,480 --> 00:46:03,920
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