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Speaker 1: So I absolutely love talking about the tiniest little particles,

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Speaker 1: the hearts of black holes, and how we could be

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Speaker 1: misunderstanding like all of it.

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Speaker 2: And I love talking about parasites, teeny tiny little wasps

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Speaker 2: and dung beetles. But judging from my husband's face at

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Speaker 2: the dinner table, it's possible that not everyone shares exactly

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Speaker 2: my interests.

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Speaker 3: So what do you want to hear about for the podcast?

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Speaker 1: We usually pick topics that excite us and we think

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Speaker 1: you'll enjoy, but you know we both have our weird

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Speaker 1: quirks and preferences, so we want to hear from you.

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Speaker 1: We'd love to answer questions you have about the universe,

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Speaker 1: what you think is extraordinary and interesting and needs more explanation.

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Speaker 1: Sometimes we turn your idea into a whole episode. Sometimes

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Speaker 1: we give you a fifteen minute answer during a listener

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Speaker 1: question session.

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Speaker 2: And the questions you send us will help us more

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Speaker 2: generally to gauge our audience's interests, which help us pick

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Speaker 2: additional topics for the future.

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Speaker 1: So please don't be shy I send us your questions.

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Speaker 1: We want to hear from you. We want this podcast

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Speaker 1: to be about what you are curious about, and today

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Speaker 1: we're tackling three fantastic, hilarious, amazing questions send to us

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Speaker 1: by listeners just like you, And if you want.

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Speaker 2: To be on the next show, you can email us

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Speaker 2: at Questions at Daniel and Kelly dot org.

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Speaker 1: Your science podcast fame.

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Speaker 2: Awaits Welcome to Daniel and Kelly's Extraordinary Universe.

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

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Speaker 1: never run out of questions.

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Speaker 3: Hi.

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Speaker 2: I'm Kelly Wiener Smith And every question I ask pleads

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Speaker 2: to even more questions.

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Speaker 1: Why is that? Do you think?

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Speaker 2: Because we know so little about everything? I think at

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Speaker 2: the end of the day.

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Speaker 1: See, we even have questions about questions, there's never an

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Speaker 1: end to them.

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Speaker 2: So my question for you today, Daniel, is when you

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Speaker 2: were working on a PhD, did you get a satisfying

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Speaker 2: answer to your big question?

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Speaker 1: You're really going to ask me that that's so embarrassing.

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Speaker 1: You know. I did a PhD which was pretty technical.

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Speaker 1: I was measuring how often two top quarks are made

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Speaker 1: and decay in a very specific way. And it was

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Speaker 1: only when I was writing up my thesis five years

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Speaker 1: into the project that I did enough reading of the

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Speaker 1: literature to understand, like, hey, is this interesting at all?

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Speaker 1: And how am I contributing to the scientific conversation? And

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Speaker 1: that's when I learned I basically wasn't. Oh no, So

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Speaker 1: what did.

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Speaker 3: You publish it? Anyway? I guess at that point you

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Speaker 3: have to.

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Speaker 1: Yeah, absolutely, you have to. And you know that's just

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Speaker 1: part of the process, because when you start graduate school,

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Speaker 1: you're like a science baby. I mean, you have your

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Speaker 1: inspiration for why you want to study particles, but you

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Speaker 1: don't know what the interesting questions are and what we

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Speaker 1: could actually learn in a reasonable amount of time. So

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Speaker 1: you rely on senior people the guide you and help

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Speaker 1: you pick a time topic and get started on it.

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Speaker 1: And so it was only when I finished my thesis

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Speaker 1: that I feel like I knew enough to know what

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Speaker 1: was interesting and what wasn't.

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Speaker 3: Oh man, that's frustrating.

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Speaker 2: I always tell the students that I work with, do

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Speaker 2: you feel like you've read enough?

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Speaker 3: Yeah? You haven't?

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Speaker 2: Keep reading, go back and read, and they're like, no, no,

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Speaker 2: I'm good. I'm like, oh, you're good, read twice as much.

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Speaker 1: Are not good? Yet?

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Speaker 2: You just need to keep reading. That solves a lot

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Speaker 2: of problems. But man, it's hard to know when to stop.

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Speaker 1: And that's why your book has such a lengthy bibliography.

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Speaker 3: At least I practice what I preach.

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Speaker 1: Yes, And how about you? Do you feel like your

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Speaker 1: thesis was exciting, was compelling that you got to answer

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Speaker 1: a big, fat, juicy question.

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Speaker 2: I was asking whether or not this brain infecting parasite

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Speaker 2: changes like some personality traits in the fish that it infects.

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Speaker 2: And after like seven years it took me a really

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Speaker 2: long time to get my PhD. The answer is like no.

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Speaker 1: But you know, negative answers are just as important, right,

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Speaker 1: you can't not publish it because the answers not exciting

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Speaker 1: or not that interesting. It's important to cross things off

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Speaker 1: the list. You know. I've been doing particle physics for decades.

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Speaker 1: I've never discovered a new particle. Every single paper I've

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Speaker 1: written is like, and we didn't find this, and we

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Speaker 1: didn't find that, and we didn't find this other thing.

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Speaker 2: I felt like I had designed a really good experiment,

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Speaker 2: and so when I decided the answer was no, I

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Speaker 2: was like, Oh, the ANSWER's really no.

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Speaker 3: I feel good.

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Speaker 2: About the answer being no, so yeah, no can be

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Speaker 2: a satisfying answer. Also, but my PhD advisor would like

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Speaker 2: me to finish publishing that paper.

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Speaker 1: Wait, still are you joking, No, I mean it.

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Speaker 3: Yeah.

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Speaker 2: I've published a lot of side projects, and actually all

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Speaker 2: of those side projects ended up becoming my dissertation. So

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Speaker 2: we have had a lot of publications together, but the

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Speaker 2: main project ended up being so massive and overwhelming and

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Speaker 2: hard to analyze that I still haven't had a chance

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Speaker 2: to write it up. But that is my twenty twenty

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Speaker 2: five project, and that's why I wrote a bunch of

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Speaker 2: my other collaborators to say, I'm not doing anything else

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Speaker 2: this year.

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Speaker 3: I'm finally going to publish my PhD.

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Speaker 1: Was it also your twenty twenty project and your twenty

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Speaker 1: fifteen projects? Yeah? Science takes a while, people, Science takes

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Speaker 1: a while.

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Speaker 2: It does, unfortunately, But you know what doesn't take a

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Speaker 2: while sending an email to.

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Speaker 3: You and me.

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Speaker 2: That's right, and our amazing listeners have done that. And

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Speaker 2: we have three fantastic questions today, all of them sort

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Speaker 2: of more Daniel centric, but we've got a lot of

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Speaker 2: Kelly centric questions queued up for our next Audience Questions episode.

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Speaker 2: But should we jump into our first audience question today?

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Speaker 1: Absolutely, let's do it. And as a reminder, we're going

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Speaker 1: to be answering this question from a listener and then

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Speaker 1: reaching out to the listener to give us a grade

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Speaker 1: to see did we answer your question or did we

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Speaker 1: just confuse even more or leave you unsatisfied with Nobody

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Speaker 1: knows the answer, which is usually the way things turn out.

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Speaker 3: But at least that's a real answer. So here we go.

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Speaker 4: I have a question about the presence of super massive

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Speaker 4: black holes in our galaxy. So my understanding is, we

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Speaker 4: have evidence that a number of smaller galaxies have merged

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Speaker 4: with the Milky Way in the past, right, and pretty

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Speaker 4: much all galaxies have super massive black holes at their center, right,

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Speaker 4: So what happened with those other black holes when they

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Speaker 4: entered our galaxy? Unless it was a direct hit, they

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Speaker 4: wouldn't have merged with our black hole immediately, right? So

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Speaker 4: how long did this merger take? And in the interim

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Speaker 4: it seems like there could have been just several super

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Speaker 4: massive black holes flying through our galaxy circling the center.

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Speaker 4: Do we have evidence of that happening? It seems like

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Speaker 4: they must have left quite a path of destruction through

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Speaker 4: the Milky Way. If not, is it strange that we

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Speaker 4: can't find evidence of this? And could any still be

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Speaker 4: out there right now?

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Speaker 3: Wow?

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Speaker 2: This is a super interesting and super informed question. Where

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Speaker 2: do we start here, Daniel, Maybe we start with what

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Speaker 2: happens when galaxies merge, because this was all sort of

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Speaker 2: a new to me.

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Speaker 1: Yeah, this is a really fascinating question, basically wondering like,

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Speaker 1: why don't we see a bunch of black holes zooming

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Speaker 1: around the center of the galaxy. Why does it seem

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Speaker 1: like there's only one in the center of the Milky Way.

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Speaker 1: Chris is a pretty sophisticated understanding of how galaxies merge,

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Speaker 1: and that's suggests to him like there should be a

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Speaker 1: bunch of black holes. And that's my favorite kind of

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Speaker 1: question when you hear a listener having internalized something about

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Speaker 1: physics and then drawing some conclusion, comparing that to the

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Speaker 1: understanding and being like, wait, some thing's not fitting here.

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Speaker 1: What am I missing? Because that's the essential process of science,

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Speaker 1: right build that model compared to the data, update it.

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Speaker 1: It's wonderful to see it happening in real time. So yeah,

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Speaker 1: I agree we should start by reminding the listeners, at

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Speaker 1: least who might not know as much as Chris does

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Speaker 1: about how galaxies come together.

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Speaker 2: Based on what you just said, I just want to

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Speaker 2: confirm is it actually the case that every galaxy has

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Speaker 2: a black hole at the middle, because I hadn't realized that.

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Speaker 2: But we've seen a lot of galaxy, so we should

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Speaker 2: know if that's a consistent thing or not.

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Speaker 1: So that's a great question. We don't have a definitive

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Speaker 1: answer because we can't look at every galaxy in the universe.

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Speaker 1: But every single galaxy we've looked at has a supermassive

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Speaker 1: black hole at the center, or we can explain where

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Speaker 1: it went, like it got kicked out, or there's a

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Speaker 1: collision or something. So there's very strong evidence that every

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Speaker 1: galaxy has a super massive black hole, but it's not

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Speaker 1: something we understand. If we try to model the formation

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Speaker 1: of those black holes are the centers of galaxies, The

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Speaker 1: models don't describe the data, like we can't get our

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Speaker 1: black holes to be as big in the models as

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Speaker 1: we see in reality, like they're huge black holes of

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Speaker 1: the center of galaxies only a billion years after the

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Speaker 1: universe forms. We have no idea how you make such

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Speaker 1: a big black hole so quickly. So there's a lot

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Speaker 1: we still don't understand about super massive black holes. For sure.

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Speaker 2: Do we know why there's a super massive black hole

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Speaker 2: at the center of every galaxy does that make sense.

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Speaker 1: We don't know why they're so big, but it makes

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Speaker 1: sense that. You know, galaxies are big pools of stuff,

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Speaker 1: and stuff pulls on itself and falls towards the center,

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Speaker 1: and eventually, if you get stuff dense enough, you're going

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Speaker 1: to get a black hole. So it makes sense to

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Speaker 1: have a black hole at the center of every galaxy.

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Speaker 1: It's the densest point, and you cross that threshold, you

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Speaker 1: get black holes.

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Speaker 2: So yeah, okay, all right, So then let's back up

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Speaker 2: to what happens when galaxies.

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Speaker 1: Merg Yeah, because Chris is asking why we don't see

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Speaker 1: multiple black holes at the center of the Milky Way

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Speaker 1: from multiple galaxies merging, and this touches on the whole

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Speaker 1: story of how galaxies form. We think that all the

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Speaker 1: galaxies we see today are made up of a bunch

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Speaker 1: of little baby galaxies that came together to make big galaxies.

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Speaker 1: So we don't think big galaxies were formed all at

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Speaker 1: once into some huge gravitational collapse in the early universe.

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Speaker 1: We think that a bunch of little galaxies were made

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Speaker 1: and then those galaxies come together to make bigger galaxies.

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Speaker 1: It's like a hierarchical bottom up formation rather than just

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Speaker 1: like a single formation of a big galaxy.

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Speaker 2: Is it easy to explain why we think it started

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Speaker 2: with little galaxies coming together as opposed to just lots

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Speaker 2: of big galaxies forming.

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Speaker 1: For a long time, there were both of those theories,

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Speaker 1: the sort of top down and the bottom up approach.

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Speaker 1: But you can tell the difference in the models, like

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Speaker 1: the age of the stars and the formation and the

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Speaker 1: structure of the galaxies are different if you start from

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Speaker 1: little ones which then build up together to make big ones.

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Speaker 1: And we can see evidence for this, for example, in

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Speaker 1: our Milky Way, and surrounding the Milky Way, we see

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Speaker 1: a bunch of little galaxies we call them dwarf galaxies

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Speaker 1: that are not fully incorporated, that are sort of in

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Speaker 1: the gravitational grasp of the Milky Way but not completely eaten.

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Speaker 1: So we see a lot of evidence for this theory

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Speaker 1: that galaxies are formed sort of bottom up.

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Speaker 2: All right, So galaxies are formed bottom up. They all

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Speaker 2: have super massive black holes at the center. I think

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Speaker 2: we did talk in another episode about how sometimes galaxies merge,

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Speaker 2: and this is one way the Earth we could all

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Speaker 2: be in trouble if we got too close and we

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Speaker 2: merged with another system that's coming back to me now.

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Speaker 1: And so these supermassive black holes at the center. Just

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Speaker 1: to remind folks, these are not little normal stellar black

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Speaker 1: holes like a black hole that you think about from

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Speaker 1: a collapsing star, Like a star burns up all of

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Speaker 1: its gas and then it can no longer resist gravity

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Speaker 1: and eventually collapses and forms a black hole. That's the

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Speaker 1: kind of thing we expect to be like ten solar

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Speaker 1: masses ten times the mass of our sun. Maybe a

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Speaker 1: super massive black hole is something that's like ten thousand,

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Speaker 1: or a million, or a billion times the mass of

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Speaker 1: our Sun. So like really extraordinarily massive objects that are

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Speaker 1: out there at the center of these galaxies. Even these

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Speaker 1: dwarf galaxies have them up to like fifty thousand times

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Speaker 1: the mass of our Sun.

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Speaker 2: So if we know that dying suns cause black holes,

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Speaker 2: how do we get super massive black holes. Is it

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Speaker 2: like a dying sun party, like they all get together

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Speaker 2: to see the sunset or something.

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Speaker 1: We don't know the answer to that. Like, if you

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Speaker 1: design a model, you say I'm going to use all

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Speaker 1: the known physics we have and the gravity, and you

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Speaker 1: create these galaxies, you get black holes at the center,

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Speaker 1: But they don't get this big, like, they don't get

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Speaker 1: as big as we see them out there in the universe.

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Speaker 1: So they get massive, and we even call them super massive,

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Speaker 1: but they don't get as big as we see so

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Speaker 1: we don't understand exactly how they form. There's lots of

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Speaker 1: crazy theories. One theory is that black holes may have

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Speaker 1: formed much much earlier, they called primordial black holes, before

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Speaker 1: even there was matter, when the universe was still cooling

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Speaker 1: and coalescing. Instead of making protons, maybe it made a

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Speaker 1: bunch of black holes. So the black holes are much

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Speaker 1: older than we think, and they've been forming matter for

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Speaker 1: a long time. Nobody's ever seen one of these primordial

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Speaker 1: black holes, you know. There's a lot of ideas for

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Speaker 1: how these black holes could have gotten so massive. But

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Speaker 1: for Chris's question, the point is all of these galaxies

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Speaker 1: come with a super massive black hole. So what happens

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Speaker 1: to the black hole during the merger right when two

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Speaker 1: galaxies come together make a bigger galaxy, to the black

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Speaker 1: holes always combine? How long does that take? Why don't

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Speaker 1: we see black holes in our milky way? This is

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Speaker 1: super fascinating because black holes are really awesome objects and

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Speaker 1: they're really massive, and the short version of the story

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Speaker 1: is that we think galaxies come together and then black

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Speaker 1: holes merge. We think that super massive black holes can

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Speaker 1: merge into bigger black holes just the same way like

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Speaker 1: two stars that are binary stars both collapse to black holes.

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Speaker 1: They can combine into a bigger black hole, and we've

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Speaker 1: seen evidence of the smaller black hole collapse in merger.

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Speaker 1: That's where the famous gravitational waves are from. They're from

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Speaker 1: two black holes orbiting each other, going faster and faster

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Speaker 1: and faster as they coalesce into a bigger black hole.

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Speaker 1: So we've seen gravitational waves from stellar mass black holes.

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Speaker 1: And then last year we saw a lot of evidence

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Speaker 1: a little bit less direct for gravitational radiation from super

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Speaker 1: massive black hole mergers, which we think correspond to galaxy mergers.

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Speaker 1: Super massive black holes at the hearts of galaxies coming together,

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Speaker 1: swirling around each other, generating gravitational radiation, and then mentionally

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Speaker 1: collapsing into a super duper massive black hole.

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Speaker 2: Is this a possible explanation for why super massive black

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Speaker 2: holes are bigger than theory predicts or has this already

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Speaker 2: been explored?

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Speaker 3: Like are they bigger?

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Speaker 2: Because actually you're just looking at one and it was

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Speaker 2: three that came together, or that doesn't explain it.

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Speaker 1: No, that doesn't explain it. We include that in our model,

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Speaker 1: and it can't describe the black holes that we see

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Speaker 1: out there, not something else, some other process that's juicing

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Speaker 1: them up. You know, there was this paper last year

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Speaker 1: about how black holes could be causing dark energy, and

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Speaker 1: this is correlation between the acceleration of the universe and

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Speaker 1: the side the super massive black holes. But people don't

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Speaker 1: really know if that's anything or nothing. There are papers

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Speaker 1: examining like the size of the bulge in the galaxy

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Speaker 1: and the size of the black hole. Those seem to

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Speaker 1: be correlated, which suggests that it's not just something local,

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Speaker 1: it's a bigger process across the galaxy. It's very active

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Speaker 1: area of research, and in a few years I think

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Speaker 1: we'll know a lot more because we're gathering a lot

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Speaker 1: more data about super massive black hole mergers from these

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Speaker 1: pulsar timing arrays. You use the whole galaxy basically as

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Speaker 1: a gravitational wave detector by looking at how the gravitational

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Speaker 1: waves ripple across pulsars. It's really super interesting. One of

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Speaker 1: the most fascinating things to me is that we actually

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Speaker 1: don't understand how these supermassive black holes merge. Like theoretically,

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Speaker 1: it's a little complicated when they get really close together.

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Speaker 2: I mean, when they get really close together, I guess

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Speaker 2: I would just assume that they like attract each other

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Speaker 2: and just like pull each other into each other.

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Speaker 3: Or is that too simple?

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Speaker 1: No, you're exactly right. And if they're heading right towards

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Speaker 1: each other, boom, they just suck into each other. But

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Speaker 1: remember they're moving asked already, and if they're not exactly

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Speaker 1: angled at each other, they're gonna end up orbiting each other. Right,

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Speaker 1: there's gonna be angular momentum. They're spinning around each other. Basically,

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Speaker 1: if one black hole passes by the other one instead

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Speaker 1: of hit directly hitting it, it's gonna swing around and

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Speaker 1: the two are gonna end up orbiting each other. Now,

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Speaker 1: if those black holes are surrounded by a bunch of

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Speaker 1: other stars, then they're gonna lose energy and they're gonna

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Speaker 1: fall towards each other. And you might be thinking, well,

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Speaker 1: what about the gravitational radiation is not gonna sap the

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Speaker 1: black hole's rotational energy so that they end up falling

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Speaker 1: towards each other. Yeah, that's true. That happens, but that's

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Speaker 1: not a lot of energy. It's not fast enough to

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Speaker 1: explain how they actually fall together. What they need is

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Speaker 1: the friction, the tugging from stars and gas and dust

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Speaker 1: to slow them down and help them fall in. Gravitational

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Speaker 1: waves are not enough. But when they get really close

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Speaker 1: and there's no other stars and it's just two black

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Speaker 1: holes orbiting each other, we don't understand why they eventually collapse.

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Speaker 1: We think that's a stable situation, like two black holes

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Speaker 1: orbiting each other with out any stars to slow them

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Speaker 1: down or whatever, they should do that for a long

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Speaker 1: long time, we don't really understand why they close that

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Speaker 1: final gap. We know that it happens because we've seen

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Speaker 1: evidence gravitational waves from those mergers, but theoretically it doesn't

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Speaker 1: quite make sense. It's called the final parsec problem. It's

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Speaker 1: still an open question right now in physics.

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Speaker 2: And I'm assuming that we don't have a lot of

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Speaker 2: these instances where you have two black holes orbiting each

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Speaker 2: other that you can look at to try to get data,

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Speaker 2: because that's probably a pretty rare thing to see.

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Speaker 1: It is hard to see because super massive black holes

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Speaker 1: are in galaxies far far away, and it's very difficult

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Speaker 1: to see these things and observe them, and the timescale

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Speaker 1: of these things is very, very long, so we have

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Speaker 1: not yet detected individuals supermassive black hole mergers. What we've

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Speaker 1: detected with these gravitational wave observatories that span the galaxy

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Speaker 1: is like a general hum from lots and lots of them,

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Speaker 1: so we know that it's happening. But if we can

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Speaker 1: get data from an individual and you're absolutely right, and

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Speaker 1: track like what's happening over those last few seconds, we

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Speaker 1: could learn a lot about how these things collapse. And

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Speaker 1: so it's something we haven't understood. But still now to

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Speaker 1: answer Chris's question, now that we have sort of the

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Speaker 1: background on like how these galaxies merge and how the

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Speaker 1: black holes mysteriously merge, even though don't quite understand it,

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Speaker 1: Chris is basically asking, if the Milky Ways made up

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Speaker 1: of all these galaxies, and those galaxies have black holes

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Speaker 1: and they merged, why don't we see a bunch of

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Speaker 1: black holes at the center of the galaxy instead of

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Speaker 1: just one right, And the answer is that the Milky

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Speaker 1: Way hasn't had a big collision recently for some reason.

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Speaker 1: The Milky Way is pretty smooth and chill. There hasn't

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Speaker 1: been a lot of activity. So if we had recently,

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Speaker 1: in the last you know, a few hundred million years,

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Speaker 1: collided with a big Mama galaxy, then yes, we probably

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Speaker 1: would have two supermassive black holes at the center swirling

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Speaker 1: around each other and we could watch it happen and

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Speaker 1: maybe learn something about this final parsec problem. But we're

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Speaker 1: sort of lucky, I guess, in that over the last

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Speaker 1: few billion years we haven't had as many collisions, which

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Speaker 1: is probably one reason why we're not as big. Like

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Speaker 1: if you look at Andrama, the nearby galaxy much bigger

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Speaker 1: than the Milky Way, it's a big Mama galaxy and

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Speaker 1: pretty soon at you in a few billion years, we

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Speaker 1: are going to collide with it and form some super

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Speaker 1: duper galaxy. But we're I guess a little bit quieter

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Speaker 1: and a little bit smaller, and that's the reason we

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Speaker 1: don't have surviving multiple super massive black holes at the center.

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Speaker 2: And just to be clear, the physicist in you would

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Speaker 2: really like to be around when our galaxy merges with

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Speaker 2: another m H but Kelly and her children would not

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Speaker 2: want to be around because that could be a very

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Speaker 2: chaotic time.

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Speaker 3: Is that right?

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Speaker 1: That would be a very chaotic time. Yeah, exactly. You know,

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Speaker 1: even though it would be far away, like the collision

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Speaker 1: of two galaxies doesn't necessarily involve a collision of stars directly.

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Speaker 1: It's a lot of gravitational perturbation. And we talked in

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Speaker 1: a whole other episode about what that would be like,

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Speaker 1: and it's pretty risky stuff. But yes, we would learn

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Speaker 1: so much about black holes and how they work, and

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Speaker 1: how galaxies form, and the history of the universe and

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Speaker 1: our place in it, and it would be totally worth it.

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Speaker 1: Sorry for your children, I.

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Speaker 3: Don't think it's going to happen in our lifetime. So

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Speaker 3: we're right.

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Speaker 2: So let's reach out to Chris and see if this

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Speaker 2: answered his question, and then we're going to take a

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Speaker 2: break before we come back for a question about setting

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Speaker 2: off nuclear weapons in extreme weather events.

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Speaker 1: So I sent our answer to Chris and he wrote

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Speaker 1: back to me in an email to say, quote, that

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Speaker 1: was a great discussion and a very satisfying answer. Thank you,

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Speaker 1: So thank you, Chris, and you're welcome.

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Speaker 3: All right, and we're back.

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Speaker 2: Our next question is from Margie, and this one is

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Speaker 2: a doozy.

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Speaker 5: The other day I heard that a certain politician wanted

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Speaker 5: to use nuclear bombs to get rid of hurricanes. Politics aside.

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Speaker 5: Even though it's a bad idea, it made me wonder

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Speaker 5: what would happen if a nuke went off in a

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Speaker 5: hurricane blow it out? What about the radiation in the ocean.

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Speaker 1: Thanks, this is a really fun question, and it's what

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Speaker 1: I've heard a few times people talking about. So I thought,

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Speaker 1: you know what, let's handle this out on the podcast

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Speaker 1: in case somebody out there with their finger on the

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Speaker 1: nuclear button happens to be a listener.

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Speaker 3: H all right.

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Speaker 2: So I thought that this was an incredible question. As

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Speaker 2: soon as I write it, I was like, oh, yeah,

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Speaker 2: I absolutely want to know the answer to this. And

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Speaker 2: you said you've heard this question before. This was totally

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Speaker 2: new to me. So let's start with how hurricanes even work.

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Speaker 2: If we want to talk about how you would blow

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Speaker 2: one out, let's know how they get started.

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Speaker 1: Yeah, hurricanes are amazing demonstration of pretty basic physics. You know.

441
00:20:40,680 --> 00:20:43,359
Speaker 1: Its heat flow combined with the rotation of the Earth

442
00:20:43,680 --> 00:20:45,440
Speaker 1: gives you this effect. And there's a little bit of

443
00:20:45,480 --> 00:20:47,680
Speaker 1: a naming thing going on here. The broader category is

444
00:20:47,720 --> 00:20:50,199
Speaker 1: called a cyclone, and if it's in the Atlantic or

445
00:20:50,240 --> 00:20:54,119
Speaker 1: the Northeastern Pacific, then you call it a cyclone. The

446
00:20:54,160 --> 00:20:57,440
Speaker 1: same storm in the northwestern Pacific you call it typhoon.

447
00:20:57,920 --> 00:21:00,000
Speaker 1: And if it's in the South Pacific or the Indian Ocean,

448
00:21:00,040 --> 00:21:02,480
Speaker 1: you call it a tropical cyclone. So you may have

449
00:21:02,560 --> 00:21:04,760
Speaker 1: heard all of these terms. They're actually all the same thing.

450
00:21:05,040 --> 00:21:08,080
Speaker 1: They're all just cyclones. Hurricanes are like our version of them.

451
00:21:08,480 --> 00:21:09,880
Speaker 3: Why why did they do that?

452
00:21:09,960 --> 00:21:12,840
Speaker 2: Were they described by different groups living in different areas

453
00:21:12,840 --> 00:21:17,200
Speaker 2: at different times and those names just stuck or science

454
00:21:17,240 --> 00:21:19,320
Speaker 2: sometimes goes a little crazy with our jargon.

455
00:21:19,440 --> 00:21:20,280
Speaker 3: Is that what happened to here?

456
00:21:20,560 --> 00:21:23,639
Speaker 1: It's actually really fun because we're not one hundred percent

457
00:21:23,680 --> 00:21:26,879
Speaker 1: clear why we have three names. I mean, the most

458
00:21:26,960 --> 00:21:29,840
Speaker 1: likely general explanation is the same reason why we have

459
00:21:29,960 --> 00:21:33,600
Speaker 1: like multiple names for carbonated beverages coke or soda or pop.

460
00:21:33,760 --> 00:21:36,600
Speaker 1: They originate in different groups organically, and then it becomes

461
00:21:36,600 --> 00:21:39,080
Speaker 1: hard to reconcile once we realize, hey, these are all

462
00:21:39,080 --> 00:21:42,440
Speaker 1: the same thing. We think the word hurricane comes from

463
00:21:42,520 --> 00:21:47,119
Speaker 1: the Caribbean god Hourcan or the Mayan god of wind hurrican.

464
00:21:47,440 --> 00:21:49,520
Speaker 1: I might be mispronouncing those, and then the words were

465
00:21:49,600 --> 00:21:53,640
Speaker 1: later adopted by Spanish colonizers. The word cyclone comes from

466
00:21:53,680 --> 00:21:57,159
Speaker 1: the Greek word cuclos, which means circle. It was coined

467
00:21:57,160 --> 00:21:59,840
Speaker 1: in eighteen forty by Henry Pittington of the East In

468
00:22:00,240 --> 00:22:04,240
Speaker 1: Company to describe storms in the South Pacific and typhoons.

469
00:22:04,320 --> 00:22:07,720
Speaker 1: That word doesn't have a clear origin. It might be

470
00:22:07,720 --> 00:22:10,919
Speaker 1: from the Greek name of a monster associated with the wind,

471
00:22:11,440 --> 00:22:14,639
Speaker 1: or a Persian word that means to blow furiously, or

472
00:22:14,680 --> 00:22:17,320
Speaker 1: we don't know exactly where that word comes from. We're like, oh,

473
00:22:17,400 --> 00:22:19,800
Speaker 1: that's actually the same thing. You call it a hurricane,

474
00:22:19,800 --> 00:22:21,879
Speaker 1: we call it a typhoon. Let's call the whole thing off.

475
00:22:22,440 --> 00:22:25,800
Speaker 1: But you know, sometimes in science it's more dramatic than that.

476
00:22:25,840 --> 00:22:29,080
Speaker 1: There's like competing groups and we think it's called the typhoon,

477
00:22:29,160 --> 00:22:31,120
Speaker 1: we call it a hurricane. And then you know their

478
00:22:31,160 --> 00:22:33,760
Speaker 1: minions propagate this kind of stuff. And we had an

479
00:22:33,760 --> 00:22:35,920
Speaker 1: event like that in particle physics, were the same particle

480
00:22:36,000 --> 00:22:39,080
Speaker 1: named by two different people, And these days we give

481
00:22:39,080 --> 00:22:41,639
Speaker 1: it both names because we couldn't settle the debate.

482
00:22:41,960 --> 00:22:45,119
Speaker 2: We have species descriptions like that. Two people didn't realize

483
00:22:45,119 --> 00:22:47,280
Speaker 2: they were naming the same species. But whoever got their

484
00:22:47,280 --> 00:22:51,159
Speaker 2: paper published first has precedents. I think maybe it differs

485
00:22:51,160 --> 00:22:53,159
Speaker 2: by field. Maybe the person who did it better. But anyway,

486
00:22:53,200 --> 00:22:55,240
Speaker 2: I've been reading papers from the nineteen hundreds and sometimes

487
00:22:55,280 --> 00:22:58,200
Speaker 2: they even do name calling and stuff. It's intense, but okay,

488
00:22:58,240 --> 00:23:01,240
Speaker 2: all right, so different names, it's all cyclones.

489
00:23:01,280 --> 00:23:02,639
Speaker 3: You say tomato, I say tomato.

490
00:23:02,880 --> 00:23:06,480
Speaker 1: Yeah, exactly what causes them? So a cyclone basically comes

491
00:23:06,480 --> 00:23:10,120
Speaker 1: from warm water. It heats and moistens the air above it. Right,

492
00:23:10,160 --> 00:23:13,280
Speaker 1: so the ocean is warm, you get hot air above it.

493
00:23:13,440 --> 00:23:16,919
Speaker 1: That hot air rises. That causes low pressure because the

494
00:23:16,920 --> 00:23:19,119
Speaker 1: air is going up. So now more air is going

495
00:23:19,200 --> 00:23:21,640
Speaker 1: to move in. So you have this effect where air

496
00:23:21,760 --> 00:23:23,920
Speaker 1: is getting sucked in and pushed up.

497
00:23:24,160 --> 00:23:24,320
Speaker 5: Right.

498
00:23:24,880 --> 00:23:27,119
Speaker 1: The second step is to get it to spin. The

499
00:23:27,160 --> 00:23:30,400
Speaker 1: reason it's spinning is because the Earth itself is spinning.

500
00:23:30,840 --> 00:23:34,600
Speaker 1: And this is super fascinating. It comes because the atmosphere

501
00:23:34,640 --> 00:23:39,240
Speaker 1: at different latitudes is spinning at different velocities. Like think

502
00:23:39,280 --> 00:23:42,240
Speaker 1: about how fast the atmosphere is moving at the poles

503
00:23:42,600 --> 00:23:45,080
Speaker 1: where the Earth is spinning. It's just in place, right.

504
00:23:45,320 --> 00:23:48,480
Speaker 1: An air molecule above the north pole is not moving anywhere.

505
00:23:48,920 --> 00:23:52,399
Speaker 1: But an air molecule above the equator it's sticking with

506
00:23:52,520 --> 00:23:55,800
Speaker 1: the land. It's going a lot faster, right, So the

507
00:23:55,880 --> 00:23:59,560
Speaker 1: air velocity depends on the latitude. The closer yurdit equator,

508
00:23:59,600 --> 00:24:02,200
Speaker 1: the fast you're going, the closer yard of the poles,

509
00:24:02,200 --> 00:24:05,399
Speaker 1: the slower you're going. All right, that's cool. Now, what

510
00:24:05,600 --> 00:24:09,320
Speaker 1: happens if you're sucking air in imagine this cyclone. We

511
00:24:09,359 --> 00:24:11,520
Speaker 1: have a low pressure region, we're sucking air in from

512
00:24:11,520 --> 00:24:14,560
Speaker 1: the north, and we're sucking air in from the south. Well,

513
00:24:14,560 --> 00:24:16,320
Speaker 1: the air that's coming from the south, if you're in

514
00:24:16,359 --> 00:24:19,000
Speaker 1: the Northern hemisphere, is going to be moving faster, and

515
00:24:19,040 --> 00:24:20,639
Speaker 1: the air that's coming from the north is going to

516
00:24:20,640 --> 00:24:23,320
Speaker 1: be moving slower. So the air moving from the north

517
00:24:23,560 --> 00:24:26,040
Speaker 1: is moving slower, it falls behind. The air moving from

518
00:24:26,040 --> 00:24:28,920
Speaker 1: the south is moving faster. It gets sped up, and

519
00:24:28,960 --> 00:24:31,760
Speaker 1: that's where the spin comes from. And that's why they

520
00:24:31,840 --> 00:24:36,040
Speaker 1: spin the opposite direction. In the Southern hemisphere toilet thing exactly,

521
00:24:36,080 --> 00:24:39,200
Speaker 1: the famous fallacious toilet thing. But this is actually true, right,

522
00:24:39,520 --> 00:24:41,600
Speaker 1: if you could flush your toilet with a hurricane, it

523
00:24:41,680 --> 00:24:45,320
Speaker 1: actually would flush a different direction in the northern Southern hemisphere,

524
00:24:45,359 --> 00:24:47,639
Speaker 1: except you couldn't call it a hurricane. You could call

525
00:24:47,680 --> 00:24:50,880
Speaker 1: it like a tropical cyclone in the South Pacific. So yeah,

526
00:24:50,920 --> 00:24:53,240
Speaker 1: in the northern hemisphere, they spin in a different direction

527
00:24:53,320 --> 00:24:55,480
Speaker 1: and in the southern hemisphere. Super cool.

528
00:24:55,760 --> 00:24:58,199
Speaker 2: Okay, And let's be clear for anyone who missed that

529
00:24:58,880 --> 00:25:03,120
Speaker 2: toilets do not flow opposite directions in different hemispheres, because

530
00:25:03,160 --> 00:25:05,000
Speaker 2: it's all about the way the holes are put in

531
00:25:05,000 --> 00:25:06,840
Speaker 2: the toilet, see right, and that just makes it go

532
00:25:06,880 --> 00:25:07,520
Speaker 2: in one direction.

533
00:25:08,000 --> 00:25:10,720
Speaker 1: I have no idea how it actually works. I just

534
00:25:10,840 --> 00:25:13,679
Speaker 1: know that it's apocryphal. Okay, Yeah, But so that's the

535
00:25:13,680 --> 00:25:16,800
Speaker 1: basic mechanism or hurricane, right, starts with warm water, you

536
00:25:16,840 --> 00:25:19,840
Speaker 1: get air rising, air rushes in from the sides. It's

537
00:25:19,840 --> 00:25:22,080
Speaker 1: coming in at different speed, so it ends up spinning.

538
00:25:22,280 --> 00:25:23,919
Speaker 1: So it's spinning because the Earth is spinning. Like if

539
00:25:23,920 --> 00:25:27,719
Speaker 1: the Earth didn't spin, we wouldn't have hurricanes or cyclones

540
00:25:27,840 --> 00:25:29,760
Speaker 1: or typhoons or any of that kind of stuff.

541
00:25:30,000 --> 00:25:34,080
Speaker 2: Okay, So ways to disrupt this weather pattern would either

542
00:25:34,160 --> 00:25:36,520
Speaker 2: be to like mess with the temperature or to like

543
00:25:36,960 --> 00:25:40,879
Speaker 2: put a giant fan in there trying to counteract the spin.

544
00:25:41,200 --> 00:25:43,640
Speaker 3: But we're talking about nukes, so nukes would heat things up.

545
00:25:44,040 --> 00:25:44,919
Speaker 3: Could that stop it?

546
00:25:45,480 --> 00:25:47,960
Speaker 1: I love the idea of using nukes because it's like,

547
00:25:48,080 --> 00:25:50,160
Speaker 1: what's the biggest thing we got? We have this hammer?

548
00:25:50,280 --> 00:25:51,760
Speaker 1: What can we do with it? I mean, you see

549
00:25:51,760 --> 00:25:53,880
Speaker 1: this in space all the time. People are like, how

550
00:25:53,880 --> 00:25:56,119
Speaker 1: do we power spaceship? What if you blow up nukes

551
00:25:56,160 --> 00:25:58,560
Speaker 1: behind it? And that's actually not a crazy idea, right,

552
00:25:58,600 --> 00:26:00,800
Speaker 1: We're going to talk about that pretty soon the podcast.

553
00:26:01,720 --> 00:26:04,000
Speaker 2: Well in Project Cloudshares was a whole project in the

554
00:26:04,080 --> 00:26:06,240
Speaker 2: US to figure out what you could use nuclear weapons for.

555
00:26:06,400 --> 00:26:09,000
Speaker 2: We use them to build like bays and stuff like that, Like,

556
00:26:09,080 --> 00:26:11,880
Speaker 2: let's blow that up too, Okay, So anyway, what about

557
00:26:11,920 --> 00:26:12,720
Speaker 2: a hurricane?

558
00:26:13,000 --> 00:26:15,720
Speaker 1: So it's not completely insane on the face of it,

559
00:26:15,800 --> 00:26:18,560
Speaker 1: because what is a hurricane? You have a hotspot. It's

560
00:26:18,560 --> 00:26:21,199
Speaker 1: all about energy flow, right, This warm air heated by

561
00:26:21,200 --> 00:26:23,440
Speaker 1: the ocean is rising and all this stuff is coming in.

562
00:26:23,680 --> 00:26:25,919
Speaker 1: So if you could like disrupt that somehow, if you

563
00:26:25,960 --> 00:26:28,959
Speaker 1: could create hotspot somewhere else, or move the heat or

564
00:26:29,000 --> 00:26:32,800
Speaker 1: disperse it or something, could you disrupt this flow? So

565
00:26:32,840 --> 00:26:35,000
Speaker 1: it's not insane, right, It's not just like, hey, I'd

566
00:26:35,040 --> 00:26:37,080
Speaker 1: love to nuke that, let's do it. But the problem

567
00:26:37,280 --> 00:26:39,840
Speaker 1: is that hurricanes a our energy flow on a much

568
00:26:39,960 --> 00:26:43,920
Speaker 1: much bigger scale than even our nuclear bombs. Like there

569
00:26:43,960 --> 00:26:47,400
Speaker 1: is so much energy captured in a hurricane. I looked

570
00:26:47,400 --> 00:26:50,959
Speaker 1: it up. Hurricanes release like one hundred tarawatts of energy,

571
00:26:51,280 --> 00:26:55,360
Speaker 1: and the global power use annually is twenty five tarrawats.

572
00:26:55,880 --> 00:26:59,040
Speaker 1: So like, this is an enormous amount of energy. It's

573
00:26:59,080 --> 00:27:01,480
Speaker 1: four times as much as like human use.

574
00:27:01,840 --> 00:27:05,320
Speaker 2: Okay, so the biggest nuclear bomb ever exploded was by

575
00:27:05,359 --> 00:27:06,200
Speaker 2: the Soviet Union.

576
00:27:06,240 --> 00:27:09,480
Speaker 3: It was tzar bomba right, mm hmm. How does that compare?

577
00:27:10,119 --> 00:27:12,560
Speaker 1: So you would have to blow that guy up every

578
00:27:12,640 --> 00:27:16,920
Speaker 1: twenty minutes to compare to the energy of a hurricane. Wow,

579
00:27:16,960 --> 00:27:19,359
Speaker 1: So it's a big deal. Like a hurricane is just

580
00:27:19,440 --> 00:27:22,280
Speaker 1: a massive movement of air. It's because the mass. Well,

581
00:27:22,320 --> 00:27:24,359
Speaker 1: there are high speeds as well. You know, these winds

582
00:27:24,400 --> 00:27:27,040
Speaker 1: can get to hundreds of miles per hour, but it's

583
00:27:27,080 --> 00:27:28,960
Speaker 1: just such a huge mass. I mean, you can see

584
00:27:28,960 --> 00:27:32,399
Speaker 1: the things from space, right, it's big. And anytime you

585
00:27:32,480 --> 00:27:34,720
Speaker 1: have something really big moving high speed, there's a lot

586
00:27:34,760 --> 00:27:37,359
Speaker 1: of energy and it would take an enormous amount of

587
00:27:37,600 --> 00:27:40,560
Speaker 1: energy to deflect it. So if you're going to nuke,

588
00:27:40,720 --> 00:27:43,200
Speaker 1: it's going to require like all of the Earth's arsenal

589
00:27:43,640 --> 00:27:46,359
Speaker 1: dropping down on this thing. It's not like a single

590
00:27:46,440 --> 00:27:49,240
Speaker 1: tactical nuke is going to deflect this thing. You want

591
00:27:49,240 --> 00:27:51,000
Speaker 1: to have an impact, it's going to have to be huge,

592
00:27:51,040 --> 00:27:53,720
Speaker 1: and then you're causing a nuclear winter. So I don't

593
00:27:53,720 --> 00:27:55,000
Speaker 1: think you really accomplish an.

594
00:27:55,240 --> 00:27:58,240
Speaker 2: You haven't solved any problems there. We started by saying

595
00:27:58,320 --> 00:28:03,199
Speaker 2: that cyclones are because of heat. Is it possible that

596
00:28:03,240 --> 00:28:05,919
Speaker 2: by trying to stop a cyclone when we set a

597
00:28:06,000 --> 00:28:08,640
Speaker 2: nuclear weapon off, we're just gonna make it worse because

598
00:28:08,680 --> 00:28:11,000
Speaker 2: that's more heat. Oh yeah, is that what would happen

599
00:28:11,040 --> 00:28:12,359
Speaker 2: or we don't know if it would get worse.

600
00:28:12,480 --> 00:28:15,520
Speaker 1: Well, hurricanes are not something we totally understand right anyway.

601
00:28:15,560 --> 00:28:17,040
Speaker 1: We can't like look at a hurricane and say we

602
00:28:17,080 --> 00:28:18,879
Speaker 1: know what's going to happen here because we understand all

603
00:28:18,880 --> 00:28:21,879
Speaker 1: the physics. We understand the microphysics, but it's such a

604
00:28:22,000 --> 00:28:25,000
Speaker 1: chaotic system that a little wrinkle here, a butterfly flaps,

605
00:28:25,000 --> 00:28:27,680
Speaker 1: that swings there, the hurricane goes somewhere else. These things

606
00:28:27,680 --> 00:28:30,000
Speaker 1: are difficult to model. We think that probably what would

607
00:28:30,000 --> 00:28:32,840
Speaker 1: happen is you'd produce a shockwave a pulsive high pressure,

608
00:28:33,080 --> 00:28:34,880
Speaker 1: but we don't think that would actually have a big

609
00:28:34,920 --> 00:28:38,800
Speaker 1: effect on like the pressure of a hurricane. In order

610
00:28:38,840 --> 00:28:41,600
Speaker 1: to change like a big category five hurricane, you do

611
00:28:41,600 --> 00:28:44,600
Speaker 1: a category two hurricane. You'd have to add like a

612
00:28:44,720 --> 00:28:48,000
Speaker 1: half ton of air for each square meter inside the

613
00:28:48,080 --> 00:28:52,280
Speaker 1: eye of the hurricane, which is like five hundred million

614
00:28:52,440 --> 00:28:55,960
Speaker 1: tons of air. So you know, it's hard to imagine

615
00:28:55,960 --> 00:28:58,560
Speaker 1: like moving that much air around in terms of like

616
00:28:58,760 --> 00:29:01,280
Speaker 1: changing the pressure. We don't have like the tool to

617
00:29:01,360 --> 00:29:04,560
Speaker 1: do this right. And you know, fundamentally, like you have

618
00:29:04,760 --> 00:29:07,320
Speaker 1: a big warm spot in the ocean, unless you're going

619
00:29:07,320 --> 00:29:11,920
Speaker 1: to completely disperse that heat, you might temporarily disorganize a hurricane,

620
00:29:11,960 --> 00:29:14,080
Speaker 1: but the same forces that create it are just going

621
00:29:14,160 --> 00:29:16,560
Speaker 1: to reorganize it. I mean, as you say, like you're

622
00:29:16,560 --> 00:29:20,080
Speaker 1: adding heat usually to the system, and so it's just

623
00:29:20,160 --> 00:29:23,160
Speaker 1: going to come back stronger, you know, like a monster

624
00:29:23,200 --> 00:29:26,320
Speaker 1: in a terrible movie. Plus you're gonna have like dumped

625
00:29:26,320 --> 00:29:29,000
Speaker 1: a bunch of radiation into your atmosphere, a very high

626
00:29:29,080 --> 00:29:31,719
Speaker 1: velocity winds that are going to go everywhere, all right.

627
00:29:31,760 --> 00:29:34,480
Speaker 2: So you have just made me even more amazed that

628
00:29:34,480 --> 00:29:37,880
Speaker 2: there are some people who don't evacuate when hurricanes come through,

629
00:29:37,960 --> 00:29:40,200
Speaker 2: because I hadn't realized how much stronger they were than

630
00:29:40,240 --> 00:29:44,640
Speaker 2: the explosions of nuclear weapons. We've established that heat equals

631
00:29:44,680 --> 00:29:48,720
Speaker 2: bad in this case, can you cool it down?

632
00:29:48,880 --> 00:29:49,480
Speaker 3: Somehow.

633
00:29:49,800 --> 00:29:51,480
Speaker 2: I'm guessing the answer is no, because this is just

634
00:29:51,600 --> 00:29:54,680
Speaker 2: energy on a scale that is uncontrollable. Yeah, has anyone

635
00:29:54,720 --> 00:29:56,240
Speaker 2: ever tried to like cool it down?

636
00:29:56,560 --> 00:29:58,719
Speaker 1: So the US government has sponsored a bunch of projects

637
00:29:58,800 --> 00:30:01,520
Speaker 1: to try to in your with hurricanes, which makes sense,

638
00:30:01,560 --> 00:30:03,920
Speaker 1: like these are destructive things. Is there anything we can do?

639
00:30:04,640 --> 00:30:08,200
Speaker 1: And in the sixties there's this project called storm Fury,

640
00:30:08,280 --> 00:30:11,400
Speaker 1: which is a pretty awesome name, where the thought was,

641
00:30:11,680 --> 00:30:15,040
Speaker 1: could we somehow disrupt the flow because the hurricane has

642
00:30:15,120 --> 00:30:18,560
Speaker 1: these walls as of clouds circulating around the center, And

643
00:30:18,640 --> 00:30:21,480
Speaker 1: they thought if they maybe seated the clouds by dumping

644
00:30:21,480 --> 00:30:24,360
Speaker 1: in a bunch of silver iodied, which nucleates ice crystals,

645
00:30:24,920 --> 00:30:28,080
Speaker 1: that this silver iodied would make these ice crystals, which

646
00:30:28,080 --> 00:30:30,560
Speaker 1: could make like a new ring of clouds, which would

647
00:30:30,560 --> 00:30:33,520
Speaker 1: somehow compete with the natural circulation of the storm and

648
00:30:33,560 --> 00:30:36,960
Speaker 1: basically disorganize it, sort of actually releasing some of the

649
00:30:37,000 --> 00:30:40,280
Speaker 1: heat by forming these ice crystals, right, releasing some of

650
00:30:40,280 --> 00:30:43,600
Speaker 1: that water, and then like growing the rainy part instead

651
00:30:43,640 --> 00:30:46,840
Speaker 1: of this spinny part. The idea was sort of reasonable,

652
00:30:47,000 --> 00:30:49,400
Speaker 1: and they actually tried it on a few hurricanes, but

653
00:30:49,480 --> 00:30:52,560
Speaker 1: it didn't work. And these days we think that probably

654
00:30:52,640 --> 00:30:55,840
Speaker 1: it failed because there isn't enough super cooled water to

655
00:30:55,920 --> 00:30:58,600
Speaker 1: react with that silver iodide to have enough of an effect.

656
00:30:59,040 --> 00:31:02,160
Speaker 1: And so people have tried stuff, nobody's ever made it work.

657
00:31:02,400 --> 00:31:04,280
Speaker 1: But you know, people are out there thinking about how

658
00:31:04,320 --> 00:31:06,760
Speaker 1: can we protect ourselves from hurricanes? What are some things

659
00:31:06,800 --> 00:31:08,880
Speaker 1: we can do? To me? This is kind of scary.

660
00:31:09,000 --> 00:31:11,960
Speaker 1: It's in the category of like geoengineering, right, like, hey,

661
00:31:11,960 --> 00:31:14,520
Speaker 1: should we put something in our atmosphere to reflect sunlight?

662
00:31:15,000 --> 00:31:17,320
Speaker 1: Like you're dumping a lot of stuff into a storm.

663
00:31:17,560 --> 00:31:19,600
Speaker 1: It could have a big effect. You have no idea

664
00:31:19,640 --> 00:31:21,440
Speaker 1: where that storm is going to go, and then you

665
00:31:21,480 --> 00:31:24,120
Speaker 1: feel responsible for it. Right What if the storm was

666
00:31:24,160 --> 00:31:26,880
Speaker 1: going to hit a fairly uninhabited area and then you

667
00:31:26,960 --> 00:31:29,680
Speaker 1: steered it towards New York City, Now you're responsible for that.

668
00:31:29,920 --> 00:31:32,360
Speaker 1: So I don't know whether it's a good idea or not.

669
00:31:32,720 --> 00:31:33,720
Speaker 3: I don't know either, you know.

670
00:31:33,720 --> 00:31:35,320
Speaker 2: I actually I love to have a whole episode on

671
00:31:35,400 --> 00:31:37,760
Speaker 2: geoengineering stuff because it is so tempting. What if there

672
00:31:37,840 --> 00:31:39,400
Speaker 2: was some way that we could all just keep doing

673
00:31:39,440 --> 00:31:42,080
Speaker 2: exactly what we're doing, but just like throw some stuff

674
00:31:42,120 --> 00:31:44,000
Speaker 2: in the sky to take care of it. But yeah,

675
00:31:44,000 --> 00:31:45,680
Speaker 2: I don't think we understand things well enough.

676
00:31:46,160 --> 00:31:48,600
Speaker 1: Yeah, but they did, and in the sixties they did

677
00:31:48,640 --> 00:31:52,160
Speaker 1: it for Hurricane Esther and Hurricane Bulah, Hurricane Debbie, and

678
00:31:52,160 --> 00:31:55,480
Speaker 1: then Hurricane Ginger in nineteen seventy one. I wasn't able

679
00:31:55,480 --> 00:31:57,440
Speaker 1: to find more recent experiments. I don't know if those

680
00:31:57,480 --> 00:32:00,800
Speaker 1: are like still classified or whatever, but it's definitely something

681
00:32:00,800 --> 00:32:03,239
Speaker 1: people tried. Nobody's ever tried a nuke a hurricane as

682
00:32:03,280 --> 00:32:06,440
Speaker 1: far as I'm aware, which I'm grateful for. Though I

683
00:32:06,520 --> 00:32:08,680
Speaker 1: know that our president elect it's an idea that he

684
00:32:08,840 --> 00:32:11,000
Speaker 1: bounced around within his previous administration.

685
00:32:11,320 --> 00:32:14,240
Speaker 2: Well, I hope he listens to our podcast and we

686
00:32:14,280 --> 00:32:15,680
Speaker 2: can help out in that way.

687
00:32:15,760 --> 00:32:18,560
Speaker 1: I also remember seeing videos during some recent hurricane in

688
00:32:18,600 --> 00:32:22,760
Speaker 1: Florida of people shooting the hurricane. It seems like, I

689
00:32:22,840 --> 00:32:25,320
Speaker 1: get what you're expressing your frustration and this is the

690
00:32:25,320 --> 00:32:28,200
Speaker 1: only tool you have, But like, you don't want the

691
00:32:28,240 --> 00:32:30,560
Speaker 1: hurricane picking up those bullets and throwing them at high

692
00:32:30,560 --> 00:32:34,280
Speaker 1: speeds at anything. So don't shoot hurricanes people with nukes

693
00:32:34,400 --> 00:32:37,400
Speaker 1: or with bullets or really anything. Just get out of there.

694
00:32:37,640 --> 00:32:39,200
Speaker 3: Yeah, don't contribute to the problem.

695
00:32:39,320 --> 00:32:39,680
Speaker 1: Just leave.

696
00:32:40,040 --> 00:32:44,520
Speaker 2: That's sound advice there. So let's see what Margie thinks

697
00:32:44,560 --> 00:32:46,600
Speaker 2: of our sound advice and see if she felt like

698
00:32:46,680 --> 00:32:48,160
Speaker 2: this was a good answer.

699
00:32:48,560 --> 00:32:51,160
Speaker 1: Maybe we can convince her to slowly slide her finger

700
00:32:51,280 --> 00:32:52,520
Speaker 1: off of that big red button.

701
00:32:54,400 --> 00:32:59,520
Speaker 2: I wonder how much power Margie has, Sparis Margie. All right, Well,

702
00:32:59,520 --> 00:33:01,720
Speaker 2: here Margie's response, and then we'll take a break.

703
00:33:02,240 --> 00:33:05,560
Speaker 6: Wow, I'm a little surprised that it would just reform

704
00:33:05,920 --> 00:33:11,000
Speaker 6: after a blast. But let's say a nuke was shot

705
00:33:11,040 --> 00:33:12,800
Speaker 6: off in a hurricane in the middle of the ocean

706
00:33:13,680 --> 00:33:16,000
Speaker 6: and then it started spreading radiation.

707
00:33:15,720 --> 00:33:16,440
Speaker 1: All over the place.

708
00:33:17,400 --> 00:33:21,560
Speaker 6: Would it still be spreading radiation when it came ashore.

709
00:33:22,480 --> 00:33:24,760
Speaker 1: Very glad we were able to answer your question, Margie,

710
00:33:24,840 --> 00:33:27,560
Speaker 1: And that's a great follow up question. Yeah, it would

711
00:33:27,600 --> 00:33:30,280
Speaker 1: be very bad to release a lot of radiation into

712
00:33:30,320 --> 00:33:33,480
Speaker 1: a hurricane. The sort of long range danger from a

713
00:33:33,480 --> 00:33:36,880
Speaker 1: bomb going off is exactly having high winds which spread

714
00:33:37,120 --> 00:33:41,120
Speaker 1: those radiactive materials around, and so dropping one into a

715
00:33:41,160 --> 00:33:45,560
Speaker 1: hurricane it's basically the worst case scenario for containing that radiation.

716
00:33:45,800 --> 00:33:47,880
Speaker 1: So yeah, the winds in the water would spread that

717
00:33:47,960 --> 00:33:51,000
Speaker 1: radiation really far and cause a lot of damage. Again,

718
00:33:51,480 --> 00:33:54,680
Speaker 1: not a good idea. Please don't drop a bomb into

719
00:33:54,720 --> 00:34:14,880
Speaker 1: a hurricane.

720
00:34:15,760 --> 00:34:19,040
Speaker 2: So Our next question is from Kevin, So here we go.

721
00:34:20,000 --> 00:34:22,319
Speaker 7: This is a Kevin from Shoay, China, and I'll have

722
00:34:22,400 --> 00:34:26,239
Speaker 7: a question about philosophy. If a photon turns into the

723
00:34:26,280 --> 00:34:30,080
Speaker 7: electron and a positron, and the electron and positron and

724
00:34:30,160 --> 00:34:34,840
Speaker 7: wiolates into another photon, are the two photons exactly the same?

725
00:34:35,560 --> 00:34:38,120
Speaker 7: If they are the same, how can the photon appear

726
00:34:38,160 --> 00:34:41,080
Speaker 7: and disappear out of the air. And if they are

727
00:34:41,239 --> 00:34:44,640
Speaker 7: the same, is there a point when the first becomes

728
00:34:44,640 --> 00:34:45,520
Speaker 7: a second?

729
00:34:45,760 --> 00:34:48,480
Speaker 1: Ooh, thank you Kevin for asking such a fun physics

730
00:34:48,480 --> 00:34:49,880
Speaker 1: slash philosophy question.

731
00:34:50,280 --> 00:34:53,520
Speaker 2: Totally love this one, and I absolutely love hearing that

732
00:34:53,520 --> 00:34:56,719
Speaker 2: we have international listeners. This totally made my day. And

733
00:34:56,840 --> 00:34:58,959
Speaker 2: Daniel is clearly the right guy to answer your question.

734
00:34:59,080 --> 00:35:00,520
Speaker 2: So what's happening Daniel?

735
00:35:00,640 --> 00:35:03,160
Speaker 1: So what's going on here is that photons, when they

736
00:35:03,160 --> 00:35:06,400
Speaker 1: fly through space, you might just imagine like, hey, it's

737
00:35:06,440 --> 00:35:09,719
Speaker 1: a little packet of energy. It wiggles through space. That's it, right,

738
00:35:10,040 --> 00:35:12,480
Speaker 1: But we also talk about photons doing other stuff, like

739
00:35:12,760 --> 00:35:15,960
Speaker 1: photons can fly along and then we say sometimes they

740
00:35:15,960 --> 00:35:19,400
Speaker 1: can turn into a pair of particles called this conversion.

741
00:35:19,440 --> 00:35:21,520
Speaker 1: Like a photon is flying along and it turns into

742
00:35:21,560 --> 00:35:25,839
Speaker 1: an electron and a positron, two particles, so maintaining the

743
00:35:25,960 --> 00:35:29,520
Speaker 1: overall charge of zero, and then those particles can annihilate,

744
00:35:29,600 --> 00:35:32,319
Speaker 1: they can turn right back into a photon. So you

745
00:35:32,320 --> 00:35:34,799
Speaker 1: can imagine like either just a photon flying along which

746
00:35:34,840 --> 00:35:36,960
Speaker 1: turns into like a little loop of particles and then

747
00:35:37,000 --> 00:35:40,680
Speaker 1: turns back into a photon. And Kevin is asking, like,

748
00:35:40,800 --> 00:35:43,759
Speaker 1: what does that mean about the photon? Is that the

749
00:35:43,800 --> 00:35:48,200
Speaker 1: same photon that comes out after this particle loop or

750
00:35:48,320 --> 00:35:50,840
Speaker 1: is it not? And if it's not, then like, exactly

751
00:35:50,880 --> 00:35:52,760
Speaker 1: when does the new photon get born?

752
00:35:53,320 --> 00:35:56,319
Speaker 2: So is this philosophically the same as the transporter problem.

753
00:35:57,800 --> 00:36:01,080
Speaker 1: It's actually very similar to the transporter and it touches

754
00:36:01,120 --> 00:36:02,920
Speaker 1: on you know, what do you mean by this photon?

755
00:36:03,200 --> 00:36:06,120
Speaker 1: And how do you kill a photon? And all sorts

756
00:36:06,120 --> 00:36:08,799
Speaker 1: of stuff, and because in the end, these are quantum processes, right,

757
00:36:08,840 --> 00:36:11,480
Speaker 1: And the transporter problem in the end comes down to

758
00:36:11,600 --> 00:36:14,640
Speaker 1: like any time an object moves from place to place,

759
00:36:14,680 --> 00:36:17,360
Speaker 1: it's equivalent to making a copy of it and destroying

760
00:36:17,360 --> 00:36:19,880
Speaker 1: the old one, especially if we're all just ripples in

761
00:36:19,960 --> 00:36:23,319
Speaker 1: quantum fields, it's just your information sliding along. And so

762
00:36:23,480 --> 00:36:27,359
Speaker 1: basically every moment in your life. You're being transported through

763
00:36:27,360 --> 00:36:30,319
Speaker 1: space and time the same way a teleporter works, just

764
00:36:30,480 --> 00:36:33,840
Speaker 1: smaller distances. And so yeah, does that matter? Are you

765
00:36:33,920 --> 00:36:36,800
Speaker 1: being killed every instant and being recreated some other place?

766
00:36:37,520 --> 00:36:39,600
Speaker 1: What does that mean about being killed? I don't know anyway,

767
00:36:39,640 --> 00:36:42,080
Speaker 1: it's a big rabbit hole of philosophy. But here we're

768
00:36:42,080 --> 00:36:43,440
Speaker 1: focusing on a single photon.

769
00:36:43,760 --> 00:36:45,600
Speaker 2: Okay, so you're not going to answer that question for

770
00:36:45,719 --> 00:36:47,920
Speaker 2: us by the end of this answer. What do we

771
00:36:48,000 --> 00:36:51,000
Speaker 2: mean then by same If it's the same photon, what

772
00:36:51,040 --> 00:36:51,640
Speaker 2: would that mean?

773
00:36:52,000 --> 00:36:54,800
Speaker 1: Yeah, so there's two issues here we have to grapple

774
00:36:54,840 --> 00:36:56,479
Speaker 1: with if we're going to think about what this means,

775
00:36:56,520 --> 00:36:58,640
Speaker 1: and that's one of them. And the short answer, the

776
00:36:58,640 --> 00:37:00,680
Speaker 1: big picture answer to this question is that there is

777
00:37:00,760 --> 00:37:04,000
Speaker 1: no good answer to this question because the picture that

778
00:37:04,040 --> 00:37:06,279
Speaker 1: I just described, and that Kevin probably has this head

779
00:37:06,280 --> 00:37:08,520
Speaker 1: and a lot of people think about for photons, it's

780
00:37:08,520 --> 00:37:13,360
Speaker 1: a cartoon picture. It's not like our microphysical explanation for

781
00:37:13,400 --> 00:37:16,239
Speaker 1: what's really happening. Like you know, in biology, you can

782
00:37:16,320 --> 00:37:19,960
Speaker 1: have a microscopic explanation. You can say, oh, the reason

783
00:37:20,040 --> 00:37:22,640
Speaker 1: you're sick is a virus came in and attacked your

784
00:37:22,640 --> 00:37:24,359
Speaker 1: cell and to penetrated the cell wall, and you can

785
00:37:24,400 --> 00:37:26,359
Speaker 1: have this picture in your mind of these tiny things

786
00:37:26,360 --> 00:37:29,800
Speaker 1: happening that explain what we're experiencing on the big scale,

787
00:37:29,920 --> 00:37:31,959
Speaker 1: and that can be reality. So if you like zoom

788
00:37:32,000 --> 00:37:34,919
Speaker 1: in with a microscope, you can actually watch it. That's awesome, right,

789
00:37:35,160 --> 00:37:37,200
Speaker 1: And we try to do the same thing in physics,

790
00:37:37,440 --> 00:37:41,160
Speaker 1: provide a microscopic explanation for what we think is happening,

791
00:37:41,560 --> 00:37:44,200
Speaker 1: and that can be very satisfying, but it's sometimes a

792
00:37:44,200 --> 00:37:47,719
Speaker 1: cartoon and it's misleading because what's happening in the microscopic

793
00:37:47,760 --> 00:37:50,880
Speaker 1: scale is fundamentally, very very different from what's happening in

794
00:37:50,920 --> 00:37:54,640
Speaker 1: biology or in the classical scale. It's not like tiny

795
00:37:54,680 --> 00:37:57,640
Speaker 1: little balls or bouncing off each other or converting into particles.

796
00:37:57,680 --> 00:37:59,800
Speaker 1: You can't slow these things down and watch them like

797
00:37:59,840 --> 00:38:02,960
Speaker 1: a movie and get a version of the microscopic story.

798
00:38:03,520 --> 00:38:05,720
Speaker 1: So you know, what we mean by a photon isn't

799
00:38:05,760 --> 00:38:08,120
Speaker 1: just like a photon is flying through space, or a

800
00:38:08,160 --> 00:38:10,480
Speaker 1: photon flies through space and makes a particle loop. It's

801
00:38:10,520 --> 00:38:13,600
Speaker 1: sort of all of those things mixed together. So that's

802
00:38:13,600 --> 00:38:15,360
Speaker 1: why we have to identify what we mean by a

803
00:38:15,400 --> 00:38:17,000
Speaker 1: photon and what we mean by same.

804
00:38:17,400 --> 00:38:19,640
Speaker 2: So does this go back to our what is a

805
00:38:19,680 --> 00:38:24,080
Speaker 2: particle discussion? And do they work as waves or strings

806
00:38:24,400 --> 00:38:27,440
Speaker 2: or so? The question is hard to answer because we

807
00:38:27,480 --> 00:38:29,640
Speaker 2: don't even really know how to describe these things.

808
00:38:29,840 --> 00:38:32,640
Speaker 1: Yeah, exactly, and Kevin is picking out one aspect of

809
00:38:32,640 --> 00:38:35,280
Speaker 1: that cartoon, and really a photon is all of those things.

810
00:38:35,320 --> 00:38:37,480
Speaker 1: So let's start by talking about what a photon is,

811
00:38:37,520 --> 00:38:39,359
Speaker 1: and then we can dig into what do we mean

812
00:38:39,400 --> 00:38:42,200
Speaker 1: by the same photon. Okay, if you think about a photon,

813
00:38:42,200 --> 00:38:44,160
Speaker 1: it's just you're thinking about a single packet of light

814
00:38:44,200 --> 00:38:47,480
Speaker 1: that goes through space quantum mechanically. Kevin is right that

815
00:38:47,520 --> 00:38:49,560
Speaker 1: the photon could do that, but it could also convert

816
00:38:49,560 --> 00:38:51,839
Speaker 1: into these par of particles and go back. It could

817
00:38:51,840 --> 00:38:54,480
Speaker 1: also convert into those pair of particles, and then those

818
00:38:54,520 --> 00:38:57,279
Speaker 1: particles emit photons, which then turn into other stuff and

819
00:38:57,320 --> 00:38:59,640
Speaker 1: turn into other stuff. There's an infinite number of things

820
00:38:59,640 --> 00:39:02,640
Speaker 1: that a fon could do when it goes from A

821
00:39:02,800 --> 00:39:05,799
Speaker 1: to B, and each of those things comes with a probability.

822
00:39:06,320 --> 00:39:08,879
Speaker 1: And when we talk about the photon, we don't mean

823
00:39:09,520 --> 00:39:12,040
Speaker 1: one of those particles in one of those stories. What

824
00:39:12,080 --> 00:39:14,960
Speaker 1: we really mean is that whole bundle. We mean the

825
00:39:15,000 --> 00:39:17,880
Speaker 1: whole thing all mixed together because we don't know what's happening,

826
00:39:18,400 --> 00:39:21,200
Speaker 1: and there is no what's really happening the photon. The

827
00:39:21,200 --> 00:39:23,359
Speaker 1: thing we think about, the thing we should identify with

828
00:39:23,960 --> 00:39:27,000
Speaker 1: is all of those possibilities, not any individual one of

829
00:39:27,000 --> 00:39:28,640
Speaker 1: them or any part of them.

830
00:39:28,880 --> 00:39:31,600
Speaker 2: So when we were doing the what is a Particle episode,

831
00:39:31,960 --> 00:39:35,280
Speaker 2: we talked about how you don't explain the wave theory

832
00:39:35,320 --> 00:39:39,680
Speaker 2: of how you describe particles until grad school. And so

833
00:39:39,880 --> 00:39:43,160
Speaker 2: this question is making me wonder how the fact that

834
00:39:43,200 --> 00:39:45,440
Speaker 2: we are all taught to think about these as like

835
00:39:45,520 --> 00:39:48,960
Speaker 2: little points that are moving around, how much does that

836
00:39:49,040 --> 00:39:52,360
Speaker 2: inhibit all of our abilities to think about these things?

837
00:39:52,480 --> 00:39:54,680
Speaker 2: Like should we be changing the way we address this

838
00:39:54,920 --> 00:39:58,240
Speaker 2: in high school? I know it's much harder to explain

839
00:39:58,280 --> 00:40:00,880
Speaker 2: it as a wave, but it's wrong. It sounds like

840
00:40:00,920 --> 00:40:01,960
Speaker 2: the way we explain it.

841
00:40:02,239 --> 00:40:06,200
Speaker 1: Yeah, quantum field theory in kindergarten. That's what I think. No,

842
00:40:06,239 --> 00:40:08,200
Speaker 1: it's a great question, and I think you're right, And

843
00:40:08,239 --> 00:40:11,840
Speaker 1: you see it in physics students as they learn this stuff,

844
00:40:11,840 --> 00:40:14,680
Speaker 1: you teach them to think about particles and then you're like, actually,

845
00:40:14,719 --> 00:40:16,600
Speaker 1: all your intuition is wrong. You have to unpack that

846
00:40:16,640 --> 00:40:19,359
Speaker 1: and learn this whole other thing. And you know, I'm

847
00:40:19,480 --> 00:40:21,880
Speaker 1: very interested in physics education. We have these conversations like

848
00:40:21,920 --> 00:40:24,120
Speaker 1: what is the right order to teach people in, But

849
00:40:24,160 --> 00:40:26,800
Speaker 1: there's sort of this canonical order that everybody uses that

850
00:40:26,960 --> 00:40:30,120
Speaker 1: sort of follows the historical development. It's like, we thought this,

851
00:40:30,560 --> 00:40:33,279
Speaker 1: then we thought that, then we thought that, And as

852
00:40:33,320 --> 00:40:35,560
Speaker 1: you move through your physics education, you sort of catch

853
00:40:35,680 --> 00:40:38,799
Speaker 1: up to modernity. And I think it is important to

854
00:40:38,880 --> 00:40:41,719
Speaker 1: understand where these ideas came from, like why people thought

855
00:40:41,760 --> 00:40:44,440
Speaker 1: this and why people thought that, because just like with

856
00:40:44,480 --> 00:40:47,200
Speaker 1: the names of hurricane and typhoon, there's a lot of

857
00:40:47,239 --> 00:40:50,280
Speaker 1: like weird, patchy stuff that doesn't really make sense unless

858
00:40:50,320 --> 00:40:52,759
Speaker 1: you understand the history. So you kind of got to

859
00:40:52,760 --> 00:40:54,719
Speaker 1: teach people the current ideas, but you also want to

860
00:40:54,719 --> 00:40:57,160
Speaker 1: give them a tour of how we got here so

861
00:40:57,200 --> 00:41:00,640
Speaker 1: they can understand why some of it seems weird and ugly.

862
00:41:02,200 --> 00:41:04,200
Speaker 1: So I don't know the right answer to your question.

863
00:41:04,480 --> 00:41:06,440
Speaker 2: Okay, I mean I see no reason why we couldn't

864
00:41:06,440 --> 00:41:10,400
Speaker 2: start with here's the wave theories and string theories of

865
00:41:10,440 --> 00:41:13,239
Speaker 2: particles and then after be like, well, here's the history.

866
00:41:13,320 --> 00:41:15,440
Speaker 2: Let's talk about how we got here m hm, so

867
00:41:15,480 --> 00:41:18,320
Speaker 2: that people would be less confused. But anyway, I'm not

868
00:41:18,360 --> 00:41:20,600
Speaker 2: a physics educator, but I guess I kind of am.

869
00:41:20,840 --> 00:41:22,920
Speaker 1: Yeah, I guess that we have opinions at least. So

870
00:41:23,080 --> 00:41:25,120
Speaker 1: in that episode about a particle, we also talked about

871
00:41:25,120 --> 00:41:27,640
Speaker 1: how you can think about particles, as you know, little

872
00:41:27,680 --> 00:41:30,600
Speaker 1: dots flying through space turning into other stuff. You could

873
00:41:30,680 --> 00:41:34,480
Speaker 1: also think of them as fields. Right, instead of imagining

874
00:41:34,600 --> 00:41:37,200
Speaker 1: a bit of stuff, imagine a field feeling the universe,

875
00:41:37,239 --> 00:41:40,719
Speaker 1: and particles are ripples in those fields, and those two

876
00:41:40,719 --> 00:41:43,880
Speaker 1: things are actually mathematically equivalent. You can think about everything

877
00:41:43,920 --> 00:41:47,440
Speaker 1: as particles and they pull on pushing each other by

878
00:41:47,640 --> 00:41:50,560
Speaker 1: passing other particles between them, or you can think of

879
00:41:50,760 --> 00:41:53,600
Speaker 1: just fields and energy is flowing between the fields. And

880
00:41:53,719 --> 00:41:55,640
Speaker 1: I think the field's picture is really helpful to think

881
00:41:55,640 --> 00:41:58,839
Speaker 1: about for this question, because what we're talking about is

882
00:41:58,880 --> 00:42:01,560
Speaker 1: not just one part of it's a particle interacting with

883
00:42:01,600 --> 00:42:05,280
Speaker 1: another particle, right, Photons turning into electrons and back and forth.

884
00:42:05,760 --> 00:42:08,000
Speaker 1: And in the field picture, that's kind of beautiful. What

885
00:42:08,080 --> 00:42:11,719
Speaker 1: we see there is two fields interacting like a photon

886
00:42:11,840 --> 00:42:14,120
Speaker 1: as it flies through the universe is not just a

887
00:42:14,239 --> 00:42:17,000
Speaker 1: ripple in the electromagnetic field, as we say, because the

888
00:42:17,000 --> 00:42:21,319
Speaker 1: electromagnetic field affects the electron field, and vice versa. So

889
00:42:21,680 --> 00:42:24,320
Speaker 1: when you say in the particle picture, okay, a photon

890
00:42:24,400 --> 00:42:26,320
Speaker 1: is flying along and you can turn into an electron

891
00:42:26,400 --> 00:42:29,200
Speaker 1: and positron and go back in the field picture, that's

892
00:42:29,200 --> 00:42:31,840
Speaker 1: the same thing as saying energy can slash from the

893
00:42:31,840 --> 00:42:34,959
Speaker 1: photon field to the electron field and back. And what's

894
00:42:35,040 --> 00:42:37,680
Speaker 1: really happening is not that there is an electron there

895
00:42:37,800 --> 00:42:39,719
Speaker 1: or there is a photon there. But the thing we

896
00:42:39,800 --> 00:42:43,359
Speaker 1: call a photon is this interaction between the two fields.

897
00:42:43,680 --> 00:42:45,400
Speaker 1: So that's the problem with putting your finger on like

898
00:42:45,520 --> 00:42:47,719
Speaker 1: is it the same photon? Well, what do you mean

899
00:42:47,719 --> 00:42:50,120
Speaker 1: by a photon? Do you mean just the electromagnetic field,

900
00:42:50,120 --> 00:42:53,040
Speaker 1: like theoretically pure concept, or do you mean the thing

901
00:42:53,080 --> 00:42:56,120
Speaker 1: we see in the universe, which is like buzzing interaction

902
00:42:56,239 --> 00:43:00,000
Speaker 1: between photons and electrons or the photon and electron fields.

903
00:42:59,760 --> 00:43:01,719
Speaker 1: That's really what a photon is. A photon that hits

904
00:43:01,719 --> 00:43:04,560
Speaker 1: your eye from Andromeda has interacted with the electron field

905
00:43:04,600 --> 00:43:06,120
Speaker 1: all the way between there and here.

906
00:43:06,280 --> 00:43:10,440
Speaker 2: Okay, can we give a two sentence answer to summarize.

907
00:43:10,080 --> 00:43:12,480
Speaker 1: Yeah, So what is a photon? A photon, I think

908
00:43:12,560 --> 00:43:15,279
Speaker 1: is all the possible things that could happen between A

909
00:43:15,360 --> 00:43:16,960
Speaker 1: and B, and when the photon is created and the

910
00:43:16,960 --> 00:43:20,800
Speaker 1: photon is observed, you can't really dig into what happens

911
00:43:20,800 --> 00:43:23,719
Speaker 1: in between because there are multiple possibilities and all of

912
00:43:23,760 --> 00:43:26,799
Speaker 1: them play a role. Right. So now, so Kevin's question,

913
00:43:26,880 --> 00:43:29,640
Speaker 1: what do we mean by the same photon? Well, you know,

914
00:43:30,040 --> 00:43:32,160
Speaker 1: I think that you can't really think about those individual

915
00:43:32,200 --> 00:43:35,320
Speaker 1: photons and say is it the same? And if you tried,

916
00:43:35,600 --> 00:43:38,080
Speaker 1: you get yourself into all sorts of other hairy misses

917
00:43:38,280 --> 00:43:41,360
Speaker 1: that we touched on earlier, Like think about an individual

918
00:43:41,400 --> 00:43:43,960
Speaker 1: photon not just flying through space, but like bouncing off

919
00:43:43,960 --> 00:43:46,480
Speaker 1: of a mirror. What happens when a photon bounces off

920
00:43:46,480 --> 00:43:49,000
Speaker 1: of a mirror, Well, we think it's absorbed and re

921
00:43:49,080 --> 00:43:52,480
Speaker 1: emitted at the right angle. Is that the same photon? Well,

922
00:43:52,520 --> 00:43:54,480
Speaker 1: you know, it's like if you shine a light in

923
00:43:54,520 --> 00:43:56,000
Speaker 1: the mirror, the light hits your eyes. We think of

924
00:43:56,000 --> 00:43:58,440
Speaker 1: the light as bouncing off and hitting your eyes, but

925
00:43:58,480 --> 00:44:01,000
Speaker 1: it's been reabsorbed and re emitted. Is that the same?

926
00:44:01,320 --> 00:44:03,520
Speaker 1: If you say that's not the same, that means that

927
00:44:03,600 --> 00:44:06,840
Speaker 1: every time particles interact, they're no longer the same particle.

928
00:44:07,239 --> 00:44:10,080
Speaker 1: But particles are interacting constantly all the time. You are

929
00:44:10,120 --> 00:44:12,799
Speaker 1: a huge pile of particles interacting, which means that you

930
00:44:12,840 --> 00:44:15,560
Speaker 1: were not the same you were a millisecond ago. So

931
00:44:15,680 --> 00:44:18,560
Speaker 1: that leads nowhere. If you say that particle interaction means

932
00:44:18,560 --> 00:44:20,719
Speaker 1: they're not the same particle anymore, then you have no

933
00:44:20,880 --> 00:44:24,600
Speaker 1: useful meaning for the word same. Then you have to say, well,

934
00:44:24,600 --> 00:44:26,799
Speaker 1: then maybe a particle is the same if it's like

935
00:44:27,200 --> 00:44:29,960
Speaker 1: mostly unchanged. You shot the photon at the wall, it

936
00:44:30,080 --> 00:44:32,400
Speaker 1: bounced off, and it's mostly the same energy and the

937
00:44:32,440 --> 00:44:34,160
Speaker 1: same frequency and all that kind of stuff. So it's

938
00:44:34,160 --> 00:44:37,560
Speaker 1: mostly the same photon even though it's interacted. So from

939
00:44:37,560 --> 00:44:39,479
Speaker 1: that point of view, then the answer to Kevin's question

940
00:44:39,480 --> 00:44:41,880
Speaker 1: would be like, yeah, it's the same photon. And I

941
00:44:41,920 --> 00:44:45,280
Speaker 1: think philosophically unpeeling it. It's a big blob of energy.

942
00:44:45,320 --> 00:44:48,960
Speaker 1: It's flowing through the universe. It's oscillating between the different fields.

943
00:44:48,960 --> 00:44:50,520
Speaker 1: It doesn't really matter. That has a chance to be

944
00:44:50,520 --> 00:44:52,479
Speaker 1: an electron here and a chance to be a photon there.

945
00:44:52,680 --> 00:44:54,840
Speaker 1: It's the same blob of energy that was sent to

946
00:44:54,840 --> 00:44:57,320
Speaker 1: you from Andromeda. So I think it's the same photon.

947
00:44:57,520 --> 00:44:59,040
Speaker 1: So does that make sense to you, Kelly? What do

948
00:44:59,080 --> 00:44:59,640
Speaker 1: you think.

949
00:44:59,680 --> 00:45:02,279
Speaker 2: Yes, all right, that makes sense to me. Here, let

950
00:45:02,320 --> 00:45:03,799
Speaker 2: me see if I can explain it.

951
00:45:03,840 --> 00:45:04,160
Speaker 3: Okay.

952
00:45:04,200 --> 00:45:08,680
Speaker 2: So the reason that it's a complicated question is because

953
00:45:08,960 --> 00:45:10,480
Speaker 2: it's hard to think of a particle as like a

954
00:45:10,520 --> 00:45:13,399
Speaker 2: point in space. They're like packets of energy that are

955
00:45:13,440 --> 00:45:16,239
Speaker 2: interacting with other packets of energy, and they can be

956
00:45:16,280 --> 00:45:17,080
Speaker 2: hard to describe.

957
00:45:17,080 --> 00:45:17,840
Speaker 3: You know, they're.

958
00:45:17,760 --> 00:45:20,040
Speaker 2: Interacting like they're a wave, like they're a string, but

959
00:45:20,080 --> 00:45:23,800
Speaker 2: they're just sort of things that are interacting with other things,

960
00:45:23,920 --> 00:45:25,960
Speaker 2: and that's what they're doing all the time. And so

961
00:45:26,040 --> 00:45:28,640
Speaker 2: to try to figure out is this the exact same

962
00:45:28,680 --> 00:45:31,160
Speaker 2: thing when part of how we understand it is that

963
00:45:31,160 --> 00:45:33,000
Speaker 2: these things are changing and interacting over.

964
00:45:32,880 --> 00:45:35,800
Speaker 1: Time, it makes it an awkward question.

965
00:45:36,120 --> 00:45:38,480
Speaker 3: Yeah, yeah, is that an okay way to summarize it?

966
00:45:38,600 --> 00:45:41,200
Speaker 1: Yeah, I think that's great. I'm giving you a PhD

967
00:45:41,320 --> 00:45:42,719
Speaker 1: in Internet physics right now?

968
00:45:42,880 --> 00:45:46,000
Speaker 2: Yes, right, okay, but grades are really important to me,

969
00:45:46,480 --> 00:45:49,279
Speaker 2: and I haven't gotten one in like fifteen years, So

970
00:45:49,440 --> 00:45:50,000
Speaker 2: can you tell me?

971
00:45:50,040 --> 00:45:51,480
Speaker 3: And I got an A. Actually I kind of feel

972
00:45:51,480 --> 00:45:53,120
Speaker 3: like that was more like a B answer.

973
00:45:53,520 --> 00:45:56,200
Speaker 1: No, that was a solid A answer. Yeah, And now

974
00:45:56,239 --> 00:45:59,600
Speaker 1: I'm curious what Kevin thinks about our answer. So in

975
00:45:59,640 --> 00:46:02,279
Speaker 1: a moment, you'll hear Kevin giving us a grade on

976
00:46:02,400 --> 00:46:04,839
Speaker 1: our physics answers to his philosophy question.

977
00:46:05,520 --> 00:46:09,319
Speaker 7: Hi Janyan Kelly, thank you for answering my question. I

978
00:46:09,320 --> 00:46:13,120
Speaker 7: think you mean that a photon is quantum mechanical, so

979
00:46:13,280 --> 00:46:16,160
Speaker 7: it's a mix of the probabilities of all the possible

980
00:46:16,239 --> 00:46:20,640
Speaker 7: things that can happen. Also, depending on the meaning of saying,

981
00:46:21,040 --> 00:46:23,880
Speaker 7: the photon is the same and not the same at

982
00:46:23,960 --> 00:46:27,600
Speaker 7: the same time, which is mind boggling. I totally love

983
00:46:27,760 --> 00:46:28,840
Speaker 7: these kinds of answers.

984
00:46:29,560 --> 00:46:32,600
Speaker 2: Thank you so much to Chris, Margie and Kevin for

985
00:46:32,640 --> 00:46:35,080
Speaker 2: their amazing questions today. We had so much fun thinking

986
00:46:35,120 --> 00:46:37,480
Speaker 2: about these problems. And if you have a question that

987
00:46:37,480 --> 00:46:39,640
Speaker 2: you would like to share with us, please write us

988
00:46:39,719 --> 00:46:42,040
Speaker 2: at questions at Daniel and Kelly dot org.

989
00:46:42,080 --> 00:46:43,640
Speaker 3: We would love to hear from you.

990
00:46:44,320 --> 00:46:46,360
Speaker 1: We would and your friends will be so impressed to

991
00:46:46,400 --> 00:46:50,160
Speaker 1: hear your voice on a podcast, especially a nerdy podcast

992
00:46:50,239 --> 00:46:50,720
Speaker 1: like ours.

993
00:46:51,040 --> 00:46:51,360
Speaker 3: Huzza.

994
00:46:51,880 --> 00:46:54,440
Speaker 1: Thanks everyone, keep asking questions and stay curious.

995
00:46:54,760 --> 00:46:55,359
Speaker 3: See you later.

996
00:47:02,520 --> 00:47:06,040
Speaker 2: Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio.

997
00:47:06,239 --> 00:47:08,800
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998
00:47:08,960 --> 00:47:11,680
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999
00:47:11,920 --> 00:47:13,560
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1000
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1001
00:47:16,680 --> 00:47:17,640
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1002
00:47:17,760 --> 00:47:20,120
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1003
00:47:20,320 --> 00:47:23,839
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1004
00:47:23,880 --> 00:47:27,040
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1005
00:47:26,960 --> 00:47:28,160
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1006
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1007
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1008
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1009
00:47:36,200 --> 00:47:37,719
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