Latest / Daniel and Kelly’s Extraordinary Universe / Listener Questions Volume #2

Transcript

Listener Questions Volume #2 · Daniel and Kelly’s Extraordinary Universe

• 0:05
  Speaker 1: So I absolutely love talking about the tiniest little particles,
• 0:10
  Speaker 1: the hearts of black holes, and how we could be
• 0:12
  Speaker 1: misunderstanding like all of it.
• 0:14
  Speaker 2: And I love talking about parasites, teeny tiny little wasps
• 0:18
  Speaker 2: and dung beetles. But judging from my husband's face at
• 0:22
  Speaker 2: the dinner table, it's possible that not everyone shares exactly
• 0:26
  Speaker 2: my interests.
• 0:27
  Speaker 3: So what do you want to hear about for the podcast?
• 0:30
  Speaker 1: We usually pick topics that excite us and we think
• 0:33
  Speaker 1: you'll enjoy, but you know we both have our weird
• 0:35
  Speaker 1: quirks and preferences, so we want to hear from you.
• 0:38
  Speaker 1: We'd love to answer questions you have about the universe,
• 0:42
  Speaker 1: what you think is extraordinary and interesting and needs more explanation.
• 0:46
  Speaker 1: Sometimes we turn your idea into a whole episode. Sometimes
• 0:49
  Speaker 1: we give you a fifteen minute answer during a listener
• 0:52
  Speaker 1: question session.
• 0:53
  Speaker 2: And the questions you send us will help us more
• 0:55
  Speaker 2: generally to gauge our audience's interests, which help us pick
• 0:59
  Speaker 2: additional topics for the future.
• 1:01
  Speaker 1: So please don't be shy I send us your questions.
• 1:03
  Speaker 1: We want to hear from you. We want this podcast
• 1:05
  Speaker 1: to be about what you are curious about, and today
• 1:08
  Speaker 1: we're tackling three fantastic, hilarious, amazing questions send to us
• 1:13
  Speaker 1: by listeners just like you, And if you want.
• 1:16
  Speaker 2: To be on the next show, you can email us
• 1:18
  Speaker 2: at Questions at Daniel and Kelly dot org.
• 1:20
  Speaker 1: Your science podcast fame.
• 1:22
  Speaker 2: Awaits Welcome to Daniel and Kelly's Extraordinary Universe.
• 1:42
  Speaker 1: Hi. I'm Daniel, I'm a particle of physicist and I've
• 1:45
  Speaker 1: never run out of questions.
• 1:47
  Speaker 3: Hi.
• 1:47
  Speaker 2: I'm Kelly Wiener Smith And every question I ask pleads
• 1:51
  Speaker 2: to even more questions.
• 1:52
  Speaker 1: Why is that? Do you think?
• 1:53
  Speaker 2: Because we know so little about everything? I think at
• 1:56
  Speaker 2: the end of the day.
• 1:57
  Speaker 1: See, we even have questions about questions, there's never an
• 2:00
  Speaker 1: end to them.
• 2:01
  Speaker 2: So my question for you today, Daniel, is when you
• 2:04
  Speaker 2: were working on a PhD, did you get a satisfying
• 2:07
  Speaker 2: answer to your big question?
• 2:10
  Speaker 1: You're really going to ask me that that's so embarrassing.
• 2:13
  Speaker 1: You know. I did a PhD which was pretty technical.
• 2:17
  Speaker 1: I was measuring how often two top quarks are made
• 2:21
  Speaker 1: and decay in a very specific way. And it was
• 2:24
  Speaker 1: only when I was writing up my thesis five years
• 2:26
  Speaker 1: into the project that I did enough reading of the
• 2:29
  Speaker 1: literature to understand, like, hey, is this interesting at all?
• 2:32
  Speaker 1: And how am I contributing to the scientific conversation? And
• 2:36
  Speaker 1: that's when I learned I basically wasn't. Oh no, So
• 2:39
  Speaker 1: what did.
• 2:40
  Speaker 3: You publish it? Anyway? I guess at that point you
• 2:41
  Speaker 3: have to.
• 2:42
  Speaker 1: Yeah, absolutely, you have to. And you know that's just
• 2:44
  Speaker 1: part of the process, because when you start graduate school,
• 2:47
  Speaker 1: you're like a science baby. I mean, you have your
• 2:49
  Speaker 1: inspiration for why you want to study particles, but you
• 2:52
  Speaker 1: don't know what the interesting questions are and what we
• 2:54
  Speaker 1: could actually learn in a reasonable amount of time. So
• 2:57
  Speaker 1: you rely on senior people the guide you and help
• 2:59
  Speaker 1: you pick a time topic and get started on it.
• 3:02
  Speaker 1: And so it was only when I finished my thesis
• 3:04
  Speaker 1: that I feel like I knew enough to know what
• 3:06
  Speaker 1: was interesting and what wasn't.
• 3:08
  Speaker 3: Oh man, that's frustrating.
• 3:10
  Speaker 2: I always tell the students that I work with, do
• 3:12
  Speaker 2: you feel like you've read enough?
• 3:13
  Speaker 3: Yeah? You haven't?
• 3:14
  Speaker 2: Keep reading, go back and read, and they're like, no, no,
• 3:16
  Speaker 2: I'm good. I'm like, oh, you're good, read twice as much.
• 3:19
  Speaker 1: Are not good? Yet?
• 3:20
  Speaker 2: You just need to keep reading. That solves a lot
• 3:22
  Speaker 2: of problems. But man, it's hard to know when to stop.
• 3:24
  Speaker 1: And that's why your book has such a lengthy bibliography.
• 3:29
  Speaker 3: At least I practice what I preach.
• 3:31
  Speaker 1: Yes, And how about you? Do you feel like your
• 3:34
  Speaker 1: thesis was exciting, was compelling that you got to answer
• 3:37
  Speaker 1: a big, fat, juicy question.
• 3:38
  Speaker 2: I was asking whether or not this brain infecting parasite
• 3:42
  Speaker 2: changes like some personality traits in the fish that it infects.
• 3:46
  Speaker 2: And after like seven years it took me a really
• 3:49
  Speaker 2: long time to get my PhD. The answer is like no.
• 3:55
  Speaker 1: But you know, negative answers are just as important, right,
• 3:58
  Speaker 1: you can't not publish it because the answers not exciting
• 4:01
  Speaker 1: or not that interesting. It's important to cross things off
• 4:04
  Speaker 1: the list. You know. I've been doing particle physics for decades.
• 4:07
  Speaker 1: I've never discovered a new particle. Every single paper I've
• 4:09
  Speaker 1: written is like, and we didn't find this, and we
• 4:12
  Speaker 1: didn't find that, and we didn't find this other thing.
• 4:15
  Speaker 2: I felt like I had designed a really good experiment,
• 4:18
  Speaker 2: and so when I decided the answer was no, I
• 4:20
  Speaker 2: was like, Oh, the ANSWER's really no.
• 4:21
  Speaker 3: I feel good.
• 4:22
  Speaker 2: About the answer being no, so yeah, no can be
• 4:24
  Speaker 2: a satisfying answer. Also, but my PhD advisor would like
• 4:27
  Speaker 2: me to finish publishing that paper.
• 4:28
  Speaker 1: Wait, still are you joking, No, I mean it.
• 4:31
  Speaker 3: Yeah.
• 4:32
  Speaker 2: I've published a lot of side projects, and actually all
• 4:36
  Speaker 2: of those side projects ended up becoming my dissertation. So
• 4:39
  Speaker 2: we have had a lot of publications together, but the
• 4:42
  Speaker 2: main project ended up being so massive and overwhelming and
• 4:46
  Speaker 2: hard to analyze that I still haven't had a chance
• 4:48
  Speaker 2: to write it up. But that is my twenty twenty
• 4:50
  Speaker 2: five project, and that's why I wrote a bunch of
• 4:52
  Speaker 2: my other collaborators to say, I'm not doing anything else
• 4:55
  Speaker 2: this year.
• 4:56
  Speaker 3: I'm finally going to publish my PhD.
• 4:58
  Speaker 1: Was it also your twenty twenty project and your twenty
• 5:00
  Speaker 1: fifteen projects? Yeah? Science takes a while, people, Science takes
• 5:05
  Speaker 1: a while.
• 5:06
  Speaker 2: It does, unfortunately, But you know what doesn't take a
• 5:09
  Speaker 2: while sending an email to.
• 5:11
  Speaker 3: You and me.
• 5:12
  Speaker 2: That's right, and our amazing listeners have done that. And
• 5:16
  Speaker 2: we have three fantastic questions today, all of them sort
• 5:19
  Speaker 2: of more Daniel centric, but we've got a lot of
• 5:21
  Speaker 2: Kelly centric questions queued up for our next Audience Questions episode.
• 5:26
  Speaker 2: But should we jump into our first audience question today?
• 5:30
  Speaker 1: Absolutely, let's do it. And as a reminder, we're going
• 5:32
  Speaker 1: to be answering this question from a listener and then
• 5:34
  Speaker 1: reaching out to the listener to give us a grade
• 5:36
  Speaker 1: to see did we answer your question or did we
• 5:39
  Speaker 1: just confuse even more or leave you unsatisfied with Nobody
• 5:43
  Speaker 1: knows the answer, which is usually the way things turn out.
• 5:47
  Speaker 3: But at least that's a real answer. So here we go.
• 5:50
  Speaker 4: I have a question about the presence of super massive
• 5:53
  Speaker 4: black holes in our galaxy. So my understanding is, we
• 5:57
  Speaker 4: have evidence that a number of smaller galaxies have merged
• 6:00
  Speaker 4: with the Milky Way in the past, right, and pretty
• 6:03
  Speaker 4: much all galaxies have super massive black holes at their center, right,
• 6:08
  Speaker 4: So what happened with those other black holes when they
• 6:12
  Speaker 4: entered our galaxy? Unless it was a direct hit, they
• 6:15
  Speaker 4: wouldn't have merged with our black hole immediately, right? So
• 6:18
  Speaker 4: how long did this merger take? And in the interim
• 6:22
  Speaker 4: it seems like there could have been just several super
• 6:24
  Speaker 4: massive black holes flying through our galaxy circling the center.
• 6:28
  Speaker 4: Do we have evidence of that happening? It seems like
• 6:31
  Speaker 4: they must have left quite a path of destruction through
• 6:34
  Speaker 4: the Milky Way. If not, is it strange that we
• 6:37
  Speaker 4: can't find evidence of this? And could any still be
• 6:40
  Speaker 4: out there right now?
• 6:41
  Speaker 3: Wow?
• 6:42
  Speaker 2: This is a super interesting and super informed question. Where
• 6:46
  Speaker 2: do we start here, Daniel, Maybe we start with what
• 6:49
  Speaker 2: happens when galaxies merge, because this was all sort of
• 6:51
  Speaker 2: a new to me.
• 6:52
  Speaker 1: Yeah, this is a really fascinating question, basically wondering like,
• 6:56
  Speaker 1: why don't we see a bunch of black holes zooming
• 6:58
  Speaker 1: around the center of the galaxy. Why does it seem
• 7:00
  Speaker 1: like there's only one in the center of the Milky Way.
• 7:03
  Speaker 1: Chris is a pretty sophisticated understanding of how galaxies merge,
• 7:06
  Speaker 1: and that's suggests to him like there should be a
• 7:08
  Speaker 1: bunch of black holes. And that's my favorite kind of
• 7:10
  Speaker 1: question when you hear a listener having internalized something about
• 7:14
  Speaker 1: physics and then drawing some conclusion, comparing that to the
• 7:17
  Speaker 1: understanding and being like, wait, some thing's not fitting here.
• 7:19
  Speaker 1: What am I missing? Because that's the essential process of science,
• 7:22
  Speaker 1: right build that model compared to the data, update it.
• 7:26
  Speaker 1: It's wonderful to see it happening in real time. So yeah,
• 7:28
  Speaker 1: I agree we should start by reminding the listeners, at
• 7:31
  Speaker 1: least who might not know as much as Chris does
• 7:33
  Speaker 1: about how galaxies come together.
• 7:35
  Speaker 2: Based on what you just said, I just want to
• 7:37
  Speaker 2: confirm is it actually the case that every galaxy has
• 7:41
  Speaker 2: a black hole at the middle, because I hadn't realized that.
• 7:44
  Speaker 2: But we've seen a lot of galaxy, so we should
• 7:46
  Speaker 2: know if that's a consistent thing or not.
• 7:48
  Speaker 1: So that's a great question. We don't have a definitive
• 7:51
  Speaker 1: answer because we can't look at every galaxy in the universe.
• 7:53
  Speaker 1: But every single galaxy we've looked at has a supermassive
• 7:56
  Speaker 1: black hole at the center, or we can explain where
• 8:00
  Speaker 1: it went, like it got kicked out, or there's a
• 8:02
  Speaker 1: collision or something. So there's very strong evidence that every
• 8:05
  Speaker 1: galaxy has a super massive black hole, but it's not
• 8:08
  Speaker 1: something we understand. If we try to model the formation
• 8:11
  Speaker 1: of those black holes are the centers of galaxies, The
• 8:14
  Speaker 1: models don't describe the data, like we can't get our
• 8:16
  Speaker 1: black holes to be as big in the models as
• 8:18
  Speaker 1: we see in reality, like they're huge black holes of
• 8:21
  Speaker 1: the center of galaxies only a billion years after the
• 8:24
  Speaker 1: universe forms. We have no idea how you make such
• 8:26
  Speaker 1: a big black hole so quickly. So there's a lot
• 8:29
  Speaker 1: we still don't understand about super massive black holes. For sure.
• 8:32
  Speaker 2: Do we know why there's a super massive black hole
• 8:34
  Speaker 2: at the center of every galaxy does that make sense.
• 8:37
  Speaker 1: We don't know why they're so big, but it makes
• 8:39
  Speaker 1: sense that. You know, galaxies are big pools of stuff,
• 8:42
  Speaker 1: and stuff pulls on itself and falls towards the center,
• 8:44
  Speaker 1: and eventually, if you get stuff dense enough, you're going
• 8:46
  Speaker 1: to get a black hole. So it makes sense to
• 8:49
  Speaker 1: have a black hole at the center of every galaxy.
• 8:50
  Speaker 1: It's the densest point, and you cross that threshold, you
• 8:53
  Speaker 1: get black holes.
• 8:54
  Speaker 2: So yeah, okay, all right, So then let's back up
• 8:57
  Speaker 2: to what happens when galaxies.
• 8:58
  Speaker 1: Merg Yeah, because Chris is asking why we don't see
• 9:01
  Speaker 1: multiple black holes at the center of the Milky Way
• 9:04
  Speaker 1: from multiple galaxies merging, and this touches on the whole
• 9:08
  Speaker 1: story of how galaxies form. We think that all the
• 9:10
  Speaker 1: galaxies we see today are made up of a bunch
• 9:13
  Speaker 1: of little baby galaxies that came together to make big galaxies.
• 9:17
  Speaker 1: So we don't think big galaxies were formed all at
• 9:19
  Speaker 1: once into some huge gravitational collapse in the early universe.
• 9:23
  Speaker 1: We think that a bunch of little galaxies were made
• 9:26
  Speaker 1: and then those galaxies come together to make bigger galaxies.
• 9:29
  Speaker 1: It's like a hierarchical bottom up formation rather than just
• 9:32
  Speaker 1: like a single formation of a big galaxy.
• 9:35
  Speaker 2: Is it easy to explain why we think it started
• 9:37
  Speaker 2: with little galaxies coming together as opposed to just lots
• 9:40
  Speaker 2: of big galaxies forming.
• 9:41
  Speaker 1: For a long time, there were both of those theories,
• 9:43
  Speaker 1: the sort of top down and the bottom up approach.
• 9:46
  Speaker 1: But you can tell the difference in the models, like
• 9:48
  Speaker 1: the age of the stars and the formation and the
• 9:51
  Speaker 1: structure of the galaxies are different if you start from
• 9:53
  Speaker 1: little ones which then build up together to make big ones.
• 9:57
  Speaker 1: And we can see evidence for this, for example, in
• 9:59
  Speaker 1: our Milky Way, and surrounding the Milky Way, we see
• 10:02
  Speaker 1: a bunch of little galaxies we call them dwarf galaxies
• 10:04
  Speaker 1: that are not fully incorporated, that are sort of in
• 10:07
  Speaker 1: the gravitational grasp of the Milky Way but not completely eaten.
• 10:11
  Speaker 1: So we see a lot of evidence for this theory
• 10:12
  Speaker 1: that galaxies are formed sort of bottom up.
• 10:15
  Speaker 2: All right, So galaxies are formed bottom up. They all
• 10:18
  Speaker 2: have super massive black holes at the center. I think
• 10:21
  Speaker 2: we did talk in another episode about how sometimes galaxies merge,
• 10:25
  Speaker 2: and this is one way the Earth we could all
• 10:27
  Speaker 2: be in trouble if we got too close and we
• 10:28
  Speaker 2: merged with another system that's coming back to me now.
• 10:31
  Speaker 1: And so these supermassive black holes at the center. Just
• 10:34
  Speaker 1: to remind folks, these are not little normal stellar black
• 10:37
  Speaker 1: holes like a black hole that you think about from
• 10:40
  Speaker 1: a collapsing star, Like a star burns up all of
• 10:42
  Speaker 1: its gas and then it can no longer resist gravity
• 10:44
  Speaker 1: and eventually collapses and forms a black hole. That's the
• 10:47
  Speaker 1: kind of thing we expect to be like ten solar
• 10:50
  Speaker 1: masses ten times the mass of our sun. Maybe a
• 10:52
  Speaker 1: super massive black hole is something that's like ten thousand,
• 10:56
  Speaker 1: or a million, or a billion times the mass of
• 10:59
  Speaker 1: our Sun. So like really extraordinarily massive objects that are
• 11:03
  Speaker 1: out there at the center of these galaxies. Even these
• 11:06
  Speaker 1: dwarf galaxies have them up to like fifty thousand times
• 11:09
  Speaker 1: the mass of our Sun.
• 11:10
  Speaker 2: So if we know that dying suns cause black holes,
• 11:15
  Speaker 2: how do we get super massive black holes. Is it
• 11:18
  Speaker 2: like a dying sun party, like they all get together
• 11:20
  Speaker 2: to see the sunset or something.
• 11:23
  Speaker 1: We don't know the answer to that. Like, if you
• 11:25
  Speaker 1: design a model, you say I'm going to use all
• 11:27
  Speaker 1: the known physics we have and the gravity, and you
• 11:29
  Speaker 1: create these galaxies, you get black holes at the center,
• 11:32
  Speaker 1: But they don't get this big, like, they don't get
• 11:34
  Speaker 1: as big as we see them out there in the universe.
• 11:37
  Speaker 1: So they get massive, and we even call them super massive,
• 11:40
  Speaker 1: but they don't get as big as we see so
• 11:42
  Speaker 1: we don't understand exactly how they form. There's lots of
• 11:45
  Speaker 1: crazy theories. One theory is that black holes may have
• 11:48
  Speaker 1: formed much much earlier, they called primordial black holes, before
• 11:51
  Speaker 1: even there was matter, when the universe was still cooling
• 11:54
  Speaker 1: and coalescing. Instead of making protons, maybe it made a
• 11:57
  Speaker 1: bunch of black holes. So the black holes are much
• 12:00
  Speaker 1: older than we think, and they've been forming matter for
• 12:02
  Speaker 1: a long time. Nobody's ever seen one of these primordial
• 12:05
  Speaker 1: black holes, you know. There's a lot of ideas for
• 12:07
  Speaker 1: how these black holes could have gotten so massive. But
• 12:10
  Speaker 1: for Chris's question, the point is all of these galaxies
• 12:13
  Speaker 1: come with a super massive black hole. So what happens
• 12:15
  Speaker 1: to the black hole during the merger right when two
• 12:17
  Speaker 1: galaxies come together make a bigger galaxy, to the black
• 12:20
  Speaker 1: holes always combine? How long does that take? Why don't
• 12:23
  Speaker 1: we see black holes in our milky way? This is
• 12:25
  Speaker 1: super fascinating because black holes are really awesome objects and
• 12:29
  Speaker 1: they're really massive, and the short version of the story
• 12:32
  Speaker 1: is that we think galaxies come together and then black
• 12:35
  Speaker 1: holes merge. We think that super massive black holes can
• 12:38
  Speaker 1: merge into bigger black holes just the same way like
• 12:41
  Speaker 1: two stars that are binary stars both collapse to black holes.
• 12:44
  Speaker 1: They can combine into a bigger black hole, and we've
• 12:48
  Speaker 1: seen evidence of the smaller black hole collapse in merger.
• 12:51
  Speaker 1: That's where the famous gravitational waves are from. They're from
• 12:54
  Speaker 1: two black holes orbiting each other, going faster and faster
• 12:57
  Speaker 1: and faster as they coalesce into a bigger black hole.
• 13:00
  Speaker 1: So we've seen gravitational waves from stellar mass black holes.
• 13:05
  Speaker 1: And then last year we saw a lot of evidence
• 13:07
  Speaker 1: a little bit less direct for gravitational radiation from super
• 13:12
  Speaker 1: massive black hole mergers, which we think correspond to galaxy mergers.
• 13:17
  Speaker 1: Super massive black holes at the hearts of galaxies coming together,
• 13:21
  Speaker 1: swirling around each other, generating gravitational radiation, and then mentionally
• 13:24
  Speaker 1: collapsing into a super duper massive black hole.
• 13:28
  Speaker 2: Is this a possible explanation for why super massive black
• 13:33
  Speaker 2: holes are bigger than theory predicts or has this already
• 13:36
  Speaker 2: been explored?
• 13:37
  Speaker 3: Like are they bigger?
• 13:38
  Speaker 2: Because actually you're just looking at one and it was
• 13:40
  Speaker 2: three that came together, or that doesn't explain it.
• 13:43
  Speaker 1: No, that doesn't explain it. We include that in our model,
• 13:45
  Speaker 1: and it can't describe the black holes that we see
• 13:48
  Speaker 1: out there, not something else, some other process that's juicing
• 13:52
  Speaker 1: them up. You know, there was this paper last year
• 13:54
  Speaker 1: about how black holes could be causing dark energy, and
• 13:56
  Speaker 1: this is correlation between the acceleration of the universe and
• 13:59
  Speaker 1: the side the super massive black holes. But people don't
• 14:02
  Speaker 1: really know if that's anything or nothing. There are papers
• 14:05
  Speaker 1: examining like the size of the bulge in the galaxy
• 14:08
  Speaker 1: and the size of the black hole. Those seem to
• 14:10
  Speaker 1: be correlated, which suggests that it's not just something local,
• 14:13
  Speaker 1: it's a bigger process across the galaxy. It's very active
• 14:17
  Speaker 1: area of research, and in a few years I think
• 14:19
  Speaker 1: we'll know a lot more because we're gathering a lot
• 14:21
  Speaker 1: more data about super massive black hole mergers from these
• 14:24
  Speaker 1: pulsar timing arrays. You use the whole galaxy basically as
• 14:28
  Speaker 1: a gravitational wave detector by looking at how the gravitational
• 14:31
  Speaker 1: waves ripple across pulsars. It's really super interesting. One of
• 14:35
  Speaker 1: the most fascinating things to me is that we actually
• 14:37
  Speaker 1: don't understand how these supermassive black holes merge. Like theoretically,
• 14:43
  Speaker 1: it's a little complicated when they get really close together.
• 14:46
  Speaker 2: I mean, when they get really close together, I guess
• 14:48
  Speaker 2: I would just assume that they like attract each other
• 14:50
  Speaker 2: and just like pull each other into each other.
• 14:53
  Speaker 3: Or is that too simple?
• 14:54
  Speaker 1: No, you're exactly right. And if they're heading right towards
• 14:56
  Speaker 1: each other, boom, they just suck into each other. But
• 14:58
  Speaker 1: remember they're moving asked already, and if they're not exactly
• 15:02
  Speaker 1: angled at each other, they're gonna end up orbiting each other. Right,
• 15:05
  Speaker 1: there's gonna be angular momentum. They're spinning around each other. Basically,
• 15:09
  Speaker 1: if one black hole passes by the other one instead
• 15:11
  Speaker 1: of hit directly hitting it, it's gonna swing around and
• 15:14
  Speaker 1: the two are gonna end up orbiting each other. Now,
• 15:16
  Speaker 1: if those black holes are surrounded by a bunch of
• 15:18
  Speaker 1: other stars, then they're gonna lose energy and they're gonna
• 15:21
  Speaker 1: fall towards each other. And you might be thinking, well,
• 15:24
  Speaker 1: what about the gravitational radiation is not gonna sap the
• 15:27
  Speaker 1: black hole's rotational energy so that they end up falling
• 15:30
  Speaker 1: towards each other. Yeah, that's true. That happens, but that's
• 15:34
  Speaker 1: not a lot of energy. It's not fast enough to
• 15:36
  Speaker 1: explain how they actually fall together. What they need is
• 15:39
  Speaker 1: the friction, the tugging from stars and gas and dust
• 15:43
  Speaker 1: to slow them down and help them fall in. Gravitational
• 15:46
  Speaker 1: waves are not enough. But when they get really close
• 15:49
  Speaker 1: and there's no other stars and it's just two black
• 15:52
  Speaker 1: holes orbiting each other, we don't understand why they eventually collapse.
• 15:56
  Speaker 1: We think that's a stable situation, like two black holes
• 15:59
  Speaker 1: orbiting each other with out any stars to slow them
• 16:01
  Speaker 1: down or whatever, they should do that for a long
• 16:03
  Speaker 1: long time, we don't really understand why they close that
• 16:07
  Speaker 1: final gap. We know that it happens because we've seen
• 16:10
  Speaker 1: evidence gravitational waves from those mergers, but theoretically it doesn't
• 16:14
  Speaker 1: quite make sense. It's called the final parsec problem. It's
• 16:17
  Speaker 1: still an open question right now in physics.
• 16:20
  Speaker 2: And I'm assuming that we don't have a lot of
• 16:22
  Speaker 2: these instances where you have two black holes orbiting each
• 16:26
  Speaker 2: other that you can look at to try to get data,
• 16:28
  Speaker 2: because that's probably a pretty rare thing to see.
• 16:30
  Speaker 1: It is hard to see because super massive black holes
• 16:32
  Speaker 1: are in galaxies far far away, and it's very difficult
• 16:36
  Speaker 1: to see these things and observe them, and the timescale
• 16:38
  Speaker 1: of these things is very, very long, so we have
• 16:41
  Speaker 1: not yet detected individuals supermassive black hole mergers. What we've
• 16:45
  Speaker 1: detected with these gravitational wave observatories that span the galaxy
• 16:49
  Speaker 1: is like a general hum from lots and lots of them,
• 16:52
  Speaker 1: so we know that it's happening. But if we can
• 16:54
  Speaker 1: get data from an individual and you're absolutely right, and
• 16:57
  Speaker 1: track like what's happening over those last few seconds, we
• 17:00
  Speaker 1: could learn a lot about how these things collapse. And
• 17:03
  Speaker 1: so it's something we haven't understood. But still now to
• 17:05
  Speaker 1: answer Chris's question, now that we have sort of the
• 17:07
  Speaker 1: background on like how these galaxies merge and how the
• 17:09
  Speaker 1: black holes mysteriously merge, even though don't quite understand it,
• 17:13
  Speaker 1: Chris is basically asking, if the Milky Ways made up
• 17:16
  Speaker 1: of all these galaxies, and those galaxies have black holes
• 17:19
  Speaker 1: and they merged, why don't we see a bunch of
• 17:21
  Speaker 1: black holes at the center of the galaxy instead of
• 17:24
  Speaker 1: just one right, And the answer is that the Milky
• 17:27
  Speaker 1: Way hasn't had a big collision recently for some reason.
• 17:30
  Speaker 1: The Milky Way is pretty smooth and chill. There hasn't
• 17:32
  Speaker 1: been a lot of activity. So if we had recently,
• 17:35
  Speaker 1: in the last you know, a few hundred million years,
• 17:37
  Speaker 1: collided with a big Mama galaxy, then yes, we probably
• 17:40
  Speaker 1: would have two supermassive black holes at the center swirling
• 17:43
  Speaker 1: around each other and we could watch it happen and
• 17:45
  Speaker 1: maybe learn something about this final parsec problem. But we're
• 17:48
  Speaker 1: sort of lucky, I guess, in that over the last
• 17:52
  Speaker 1: few billion years we haven't had as many collisions, which
• 17:55
  Speaker 1: is probably one reason why we're not as big. Like
• 17:57
  Speaker 1: if you look at Andrama, the nearby galaxy much bigger
• 18:01
  Speaker 1: than the Milky Way, it's a big Mama galaxy and
• 18:04
  Speaker 1: pretty soon at you in a few billion years, we
• 18:06
  Speaker 1: are going to collide with it and form some super
• 18:08
  Speaker 1: duper galaxy. But we're I guess a little bit quieter
• 18:11
  Speaker 1: and a little bit smaller, and that's the reason we
• 18:13
  Speaker 1: don't have surviving multiple super massive black holes at the center.
• 18:17
  Speaker 2: And just to be clear, the physicist in you would
• 18:19
  Speaker 2: really like to be around when our galaxy merges with
• 18:22
  Speaker 2: another m H but Kelly and her children would not
• 18:25
  Speaker 2: want to be around because that could be a very
• 18:27
  Speaker 2: chaotic time.
• 18:28
  Speaker 3: Is that right?
• 18:29
  Speaker 1: That would be a very chaotic time. Yeah, exactly. You know,
• 18:32
  Speaker 1: even though it would be far away, like the collision
• 18:33
  Speaker 1: of two galaxies doesn't necessarily involve a collision of stars directly.
• 18:37
  Speaker 1: It's a lot of gravitational perturbation. And we talked in
• 18:41
  Speaker 1: a whole other episode about what that would be like,
• 18:43
  Speaker 1: and it's pretty risky stuff. But yes, we would learn
• 18:46
  Speaker 1: so much about black holes and how they work, and
• 18:48
  Speaker 1: how galaxies form, and the history of the universe and
• 18:51
  Speaker 1: our place in it, and it would be totally worth it.
• 18:54
  Speaker 1: Sorry for your children, I.
• 18:56
  Speaker 3: Don't think it's going to happen in our lifetime. So
• 18:58
  Speaker 3: we're right.
• 18:58
  Speaker 2: So let's reach out to Chris and see if this
• 19:02
  Speaker 2: answered his question, and then we're going to take a
• 19:04
  Speaker 2: break before we come back for a question about setting
• 19:06
  Speaker 2: off nuclear weapons in extreme weather events.
• 19:10
  Speaker 1: So I sent our answer to Chris and he wrote
• 19:12
  Speaker 1: back to me in an email to say, quote, that
• 19:15
  Speaker 1: was a great discussion and a very satisfying answer. Thank you,
• 19:19
  Speaker 1: So thank you, Chris, and you're welcome.
• 19:40
  Speaker 3: All right, and we're back.
• 19:42
  Speaker 2: Our next question is from Margie, and this one is
• 19:45
  Speaker 2: a doozy.
• 19:46
  Speaker 5: The other day I heard that a certain politician wanted
• 19:49
  Speaker 5: to use nuclear bombs to get rid of hurricanes. Politics aside.
• 19:53
  Speaker 5: Even though it's a bad idea, it made me wonder
• 19:56
  Speaker 5: what would happen if a nuke went off in a
• 19:58
  Speaker 5: hurricane blow it out? What about the radiation in the ocean.
• 20:03
  Speaker 1: Thanks, this is a really fun question, and it's what
• 20:08
  Speaker 1: I've heard a few times people talking about. So I thought,
• 20:11
  Speaker 1: you know what, let's handle this out on the podcast
• 20:13
  Speaker 1: in case somebody out there with their finger on the
• 20:16
  Speaker 1: nuclear button happens to be a listener.
• 20:18
  Speaker 3: H all right.
• 20:19
  Speaker 2: So I thought that this was an incredible question. As
• 20:22
  Speaker 2: soon as I write it, I was like, oh, yeah,
• 20:24
  Speaker 2: I absolutely want to know the answer to this. And
• 20:26
  Speaker 2: you said you've heard this question before. This was totally
• 20:28
  Speaker 2: new to me. So let's start with how hurricanes even work.
• 20:32
  Speaker 2: If we want to talk about how you would blow
• 20:34
  Speaker 2: one out, let's know how they get started.
• 20:36
  Speaker 1: Yeah, hurricanes are amazing demonstration of pretty basic physics. You know.
• 20:40
  Speaker 1: Its heat flow combined with the rotation of the Earth
• 20:43
  Speaker 1: gives you this effect. And there's a little bit of
• 20:45
  Speaker 1: a naming thing going on here. The broader category is
• 20:47
  Speaker 1: called a cyclone, and if it's in the Atlantic or
• 20:50
  Speaker 1: the Northeastern Pacific, then you call it a cyclone. The
• 20:54
  Speaker 1: same storm in the northwestern Pacific you call it typhoon.
• 20:57
  Speaker 1: And if it's in the South Pacific or the Indian Ocean,
• 21:00
  Speaker 1: you call it a tropical cyclone. So you may have
• 21:02
  Speaker 1: heard all of these terms. They're actually all the same thing.
• 21:05
  Speaker 1: They're all just cyclones. Hurricanes are like our version of them.
• 21:08
  Speaker 3: Why why did they do that?
• 21:09
  Speaker 2: Were they described by different groups living in different areas
• 21:12
  Speaker 2: at different times and those names just stuck or science
• 21:17
  Speaker 2: sometimes goes a little crazy with our jargon.
• 21:19
  Speaker 3: Is that what happened to here?
• 21:20
  Speaker 1: It's actually really fun because we're not one hundred percent
• 21:23
  Speaker 1: clear why we have three names. I mean, the most
• 21:26
  Speaker 1: likely general explanation is the same reason why we have
• 21:29
  Speaker 1: like multiple names for carbonated beverages coke or soda or pop.
• 21:33
  Speaker 1: They originate in different groups organically, and then it becomes
• 21:36
  Speaker 1: hard to reconcile once we realize, hey, these are all
• 21:39
  Speaker 1: the same thing. We think the word hurricane comes from
• 21:42
  Speaker 1: the Caribbean god Hourcan or the Mayan god of wind hurrican.
• 21:47
  Speaker 1: I might be mispronouncing those, and then the words were
• 21:49
  Speaker 1: later adopted by Spanish colonizers. The word cyclone comes from
• 21:53
  Speaker 1: the Greek word cuclos, which means circle. It was coined
• 21:57
  Speaker 1: in eighteen forty by Henry Pittington of the East In
• 22:00
  Speaker 1: Company to describe storms in the South Pacific and typhoons.
• 22:04
  Speaker 1: That word doesn't have a clear origin. It might be
• 22:07
  Speaker 1: from the Greek name of a monster associated with the wind,
• 22:11
  Speaker 1: or a Persian word that means to blow furiously, or
• 22:14
  Speaker 1: we don't know exactly where that word comes from. We're like, oh,
• 22:17
  Speaker 1: that's actually the same thing. You call it a hurricane,
• 22:19
  Speaker 1: we call it a typhoon. Let's call the whole thing off.
• 22:22
  Speaker 1: But you know, sometimes in science it's more dramatic than that.
• 22:25
  Speaker 1: There's like competing groups and we think it's called the typhoon,
• 22:29
  Speaker 1: we call it a hurricane. And then you know their
• 22:31
  Speaker 1: minions propagate this kind of stuff. And we had an
• 22:33
  Speaker 1: event like that in particle physics, were the same particle
• 22:36
  Speaker 1: named by two different people, And these days we give
• 22:39
  Speaker 1: it both names because we couldn't settle the debate.
• 22:41
  Speaker 2: We have species descriptions like that. Two people didn't realize
• 22:45
  Speaker 2: they were naming the same species. But whoever got their
• 22:47
  Speaker 2: paper published first has precedents. I think maybe it differs
• 22:51
  Speaker 2: by field. Maybe the person who did it better. But anyway,
• 22:53
  Speaker 2: I've been reading papers from the nineteen hundreds and sometimes
• 22:55
  Speaker 2: they even do name calling and stuff. It's intense, but okay,
• 22:58
  Speaker 2: all right, so different names, it's all cyclones.
• 23:01
  Speaker 3: You say tomato, I say tomato.
• 23:02
  Speaker 1: Yeah, exactly what causes them? So a cyclone basically comes
• 23:06
  Speaker 1: from warm water. It heats and moistens the air above it. Right,
• 23:10
  Speaker 1: so the ocean is warm, you get hot air above it.
• 23:13
  Speaker 1: That hot air rises. That causes low pressure because the
• 23:16
  Speaker 1: air is going up. So now more air is going
• 23:19
  Speaker 1: to move in. So you have this effect where air
• 23:21
  Speaker 1: is getting sucked in and pushed up.
• 23:24
  Speaker 5: Right.
• 23:24
  Speaker 1: The second step is to get it to spin. The
• 23:27
  Speaker 1: reason it's spinning is because the Earth itself is spinning.
• 23:30
  Speaker 1: And this is super fascinating. It comes because the atmosphere
• 23:34
  Speaker 1: at different latitudes is spinning at different velocities. Like think
• 23:39
  Speaker 1: about how fast the atmosphere is moving at the poles
• 23:42
  Speaker 1: where the Earth is spinning. It's just in place, right.
• 23:45
  Speaker 1: An air molecule above the north pole is not moving anywhere.
• 23:48
  Speaker 1: But an air molecule above the equator it's sticking with
• 23:52
  Speaker 1: the land. It's going a lot faster, right, So the
• 23:55
  Speaker 1: air velocity depends on the latitude. The closer yurdit equator,
• 23:59
  Speaker 1: the fast you're going, the closer yard of the poles,
• 24:02
  Speaker 1: the slower you're going. All right, that's cool. Now, what
• 24:05
  Speaker 1: happens if you're sucking air in imagine this cyclone. We
• 24:09
  Speaker 1: have a low pressure region, we're sucking air in from
• 24:11
  Speaker 1: the north, and we're sucking air in from the south. Well,
• 24:14
  Speaker 1: the air that's coming from the south, if you're in
• 24:16
  Speaker 1: the Northern hemisphere, is going to be moving faster, and
• 24:19
  Speaker 1: the air that's coming from the north is going to
• 24:20
  Speaker 1: be moving slower. So the air moving from the north
• 24:23
  Speaker 1: is moving slower, it falls behind. The air moving from
• 24:26
  Speaker 1: the south is moving faster. It gets sped up, and
• 24:28
  Speaker 1: that's where the spin comes from. And that's why they
• 24:31
  Speaker 1: spin the opposite direction. In the Southern hemisphere toilet thing exactly,
• 24:36
  Speaker 1: the famous fallacious toilet thing. But this is actually true, right,
• 24:39
  Speaker 1: if you could flush your toilet with a hurricane, it
• 24:41
  Speaker 1: actually would flush a different direction in the northern Southern hemisphere,
• 24:45
  Speaker 1: except you couldn't call it a hurricane. You could call
• 24:47
  Speaker 1: it like a tropical cyclone in the South Pacific. So yeah,
• 24:50
  Speaker 1: in the northern hemisphere, they spin in a different direction
• 24:53
  Speaker 1: and in the southern hemisphere. Super cool.
• 24:55
  Speaker 2: Okay, And let's be clear for anyone who missed that
• 24:58
  Speaker 2: toilets do not flow opposite directions in different hemispheres, because
• 25:03
  Speaker 2: it's all about the way the holes are put in
• 25:05
  Speaker 2: the toilet, see right, and that just makes it go
• 25:06
  Speaker 2: in one direction.
• 25:08
  Speaker 1: I have no idea how it actually works. I just
• 25:10
  Speaker 1: know that it's apocryphal. Okay, Yeah, But so that's the
• 25:13
  Speaker 1: basic mechanism or hurricane, right, starts with warm water, you
• 25:16
  Speaker 1: get air rising, air rushes in from the sides. It's
• 25:19
  Speaker 1: coming in at different speed, so it ends up spinning.
• 25:22
  Speaker 1: So it's spinning because the Earth is spinning. Like if
• 25:23
  Speaker 1: the Earth didn't spin, we wouldn't have hurricanes or cyclones
• 25:27
  Speaker 1: or typhoons or any of that kind of stuff.
• 25:30
  Speaker 2: Okay, So ways to disrupt this weather pattern would either
• 25:34
  Speaker 2: be to like mess with the temperature or to like
• 25:36
  Speaker 2: put a giant fan in there trying to counteract the spin.
• 25:41
  Speaker 3: But we're talking about nukes, so nukes would heat things up.
• 25:44
  Speaker 3: Could that stop it?
• 25:45
  Speaker 1: I love the idea of using nukes because it's like,
• 25:48
  Speaker 1: what's the biggest thing we got? We have this hammer?
• 25:50
  Speaker 1: What can we do with it? I mean, you see
• 25:51
  Speaker 1: this in space all the time. People are like, how
• 25:53
  Speaker 1: do we power spaceship? What if you blow up nukes
• 25:56
  Speaker 1: behind it? And that's actually not a crazy idea, right,
• 25:58
  Speaker 1: We're going to talk about that pretty soon the podcast.
• 26:01
  Speaker 2: Well in Project Cloudshares was a whole project in the
• 26:04
  Speaker 2: US to figure out what you could use nuclear weapons for.
• 26:06
  Speaker 2: We use them to build like bays and stuff like that, Like,
• 26:09
  Speaker 2: let's blow that up too, Okay, So anyway, what about
• 26:11
  Speaker 2: a hurricane?
• 26:13
  Speaker 1: So it's not completely insane on the face of it,
• 26:15
  Speaker 1: because what is a hurricane? You have a hotspot. It's
• 26:18
  Speaker 1: all about energy flow, right, This warm air heated by
• 26:21
  Speaker 1: the ocean is rising and all this stuff is coming in.
• 26:23
  Speaker 1: So if you could like disrupt that somehow, if you
• 26:25
  Speaker 1: could create hotspot somewhere else, or move the heat or
• 26:29
  Speaker 1: disperse it or something, could you disrupt this flow? So
• 26:32
  Speaker 1: it's not insane, right, It's not just like, hey, I'd
• 26:35
  Speaker 1: love to nuke that, let's do it. But the problem
• 26:37
  Speaker 1: is that hurricanes a our energy flow on a much
• 26:39
  Speaker 1: much bigger scale than even our nuclear bombs. Like there
• 26:43
  Speaker 1: is so much energy captured in a hurricane. I looked
• 26:47
  Speaker 1: it up. Hurricanes release like one hundred tarawatts of energy,
• 26:51
  Speaker 1: and the global power use annually is twenty five tarrawats.
• 26:55
  Speaker 1: So like, this is an enormous amount of energy. It's
• 26:59
  Speaker 1: four times as much as like human use.
• 27:01
  Speaker 2: Okay, so the biggest nuclear bomb ever exploded was by
• 27:05
  Speaker 2: the Soviet Union.
• 27:06
  Speaker 3: It was tzar bomba right, mm hmm. How does that compare?
• 27:10
  Speaker 1: So you would have to blow that guy up every
• 27:12
  Speaker 1: twenty minutes to compare to the energy of a hurricane. Wow,
• 27:16
  Speaker 1: So it's a big deal. Like a hurricane is just
• 27:19
  Speaker 1: a massive movement of air. It's because the mass. Well,
• 27:22
  Speaker 1: there are high speeds as well. You know, these winds
• 27:24
  Speaker 1: can get to hundreds of miles per hour, but it's
• 27:27
  Speaker 1: just such a huge mass. I mean, you can see
• 27:28
  Speaker 1: the things from space, right, it's big. And anytime you
• 27:32
  Speaker 1: have something really big moving high speed, there's a lot
• 27:34
  Speaker 1: of energy and it would take an enormous amount of
• 27:37
  Speaker 1: energy to deflect it. So if you're going to nuke,
• 27:40
  Speaker 1: it's going to require like all of the Earth's arsenal
• 27:43
  Speaker 1: dropping down on this thing. It's not like a single
• 27:46
  Speaker 1: tactical nuke is going to deflect this thing. You want
• 27:49
  Speaker 1: to have an impact, it's going to have to be huge,
• 27:51
  Speaker 1: and then you're causing a nuclear winter. So I don't
• 27:53
  Speaker 1: think you really accomplish an.
• 27:55
  Speaker 2: You haven't solved any problems there. We started by saying
• 27:58
  Speaker 2: that cyclones are because of heat. Is it possible that
• 28:03
  Speaker 2: by trying to stop a cyclone when we set a
• 28:06
  Speaker 2: nuclear weapon off, we're just gonna make it worse because
• 28:08
  Speaker 2: that's more heat. Oh yeah, is that what would happen
• 28:11
  Speaker 2: or we don't know if it would get worse.
• 28:12
  Speaker 1: Well, hurricanes are not something we totally understand right anyway.
• 28:15
  Speaker 1: We can't like look at a hurricane and say we
• 28:17
  Speaker 1: know what's going to happen here because we understand all
• 28:18
  Speaker 1: the physics. We understand the microphysics, but it's such a
• 28:22
  Speaker 1: chaotic system that a little wrinkle here, a butterfly flaps,
• 28:25
  Speaker 1: that swings there, the hurricane goes somewhere else. These things
• 28:27
  Speaker 1: are difficult to model. We think that probably what would
• 28:30
  Speaker 1: happen is you'd produce a shockwave a pulsive high pressure,
• 28:33
  Speaker 1: but we don't think that would actually have a big
• 28:34
  Speaker 1: effect on like the pressure of a hurricane. In order
• 28:38
  Speaker 1: to change like a big category five hurricane, you do
• 28:41
  Speaker 1: a category two hurricane. You'd have to add like a
• 28:44
  Speaker 1: half ton of air for each square meter inside the
• 28:48
  Speaker 1: eye of the hurricane, which is like five hundred million
• 28:52
  Speaker 1: tons of air. So you know, it's hard to imagine
• 28:55
  Speaker 1: like moving that much air around in terms of like
• 28:58
  Speaker 1: changing the pressure. We don't have like the tool to
• 29:01
  Speaker 1: do this right. And you know, fundamentally, like you have
• 29:04
  Speaker 1: a big warm spot in the ocean, unless you're going
• 29:07
  Speaker 1: to completely disperse that heat, you might temporarily disorganize a hurricane,
• 29:11
  Speaker 1: but the same forces that create it are just going
• 29:14
  Speaker 1: to reorganize it. I mean, as you say, like you're
• 29:16
  Speaker 1: adding heat usually to the system, and so it's just
• 29:20
  Speaker 1: going to come back stronger, you know, like a monster
• 29:23
  Speaker 1: in a terrible movie. Plus you're gonna have like dumped
• 29:26
  Speaker 1: a bunch of radiation into your atmosphere, a very high
• 29:29
  Speaker 1: velocity winds that are going to go everywhere, all right.
• 29:31
  Speaker 2: So you have just made me even more amazed that
• 29:34
  Speaker 2: there are some people who don't evacuate when hurricanes come through,
• 29:37
  Speaker 2: because I hadn't realized how much stronger they were than
• 29:40
  Speaker 2: the explosions of nuclear weapons. We've established that heat equals
• 29:44
  Speaker 2: bad in this case, can you cool it down?
• 29:48
  Speaker 3: Somehow.
• 29:49
  Speaker 2: I'm guessing the answer is no, because this is just
• 29:51
  Speaker 2: energy on a scale that is uncontrollable. Yeah, has anyone
• 29:54
  Speaker 2: ever tried to like cool it down?
• 29:56
  Speaker 1: So the US government has sponsored a bunch of projects
• 29:58
  Speaker 1: to try to in your with hurricanes, which makes sense,
• 30:01
  Speaker 1: like these are destructive things. Is there anything we can do?
• 30:04
  Speaker 1: And in the sixties there's this project called storm Fury,
• 30:08
  Speaker 1: which is a pretty awesome name, where the thought was,
• 30:11
  Speaker 1: could we somehow disrupt the flow because the hurricane has
• 30:15
  Speaker 1: these walls as of clouds circulating around the center, And
• 30:18
  Speaker 1: they thought if they maybe seated the clouds by dumping
• 30:21
  Speaker 1: in a bunch of silver iodied, which nucleates ice crystals,
• 30:24
  Speaker 1: that this silver iodied would make these ice crystals, which
• 30:28
  Speaker 1: could make like a new ring of clouds, which would
• 30:30
  Speaker 1: somehow compete with the natural circulation of the storm and
• 30:33
  Speaker 1: basically disorganize it, sort of actually releasing some of the
• 30:37
  Speaker 1: heat by forming these ice crystals, right, releasing some of
• 30:40
  Speaker 1: that water, and then like growing the rainy part instead
• 30:43
  Speaker 1: of this spinny part. The idea was sort of reasonable,
• 30:47
  Speaker 1: and they actually tried it on a few hurricanes, but
• 30:49
  Speaker 1: it didn't work. And these days we think that probably
• 30:52
  Speaker 1: it failed because there isn't enough super cooled water to
• 30:55
  Speaker 1: react with that silver iodide to have enough of an effect.
• 30:59
  Speaker 1: And so people have tried stuff, nobody's ever made it work.
• 31:02
  Speaker 1: But you know, people are out there thinking about how
• 31:04
  Speaker 1: can we protect ourselves from hurricanes? What are some things
• 31:06
  Speaker 1: we can do? To me? This is kind of scary.
• 31:09
  Speaker 1: It's in the category of like geoengineering, right, like, hey,
• 31:11
  Speaker 1: should we put something in our atmosphere to reflect sunlight?
• 31:15
  Speaker 1: Like you're dumping a lot of stuff into a storm.
• 31:17
  Speaker 1: It could have a big effect. You have no idea
• 31:19
  Speaker 1: where that storm is going to go, and then you
• 31:21
  Speaker 1: feel responsible for it. Right What if the storm was
• 31:24
  Speaker 1: going to hit a fairly uninhabited area and then you
• 31:26
  Speaker 1: steered it towards New York City, Now you're responsible for that.
• 31:29
  Speaker 1: So I don't know whether it's a good idea or not.
• 31:32
  Speaker 3: I don't know either, you know.
• 31:33
  Speaker 2: I actually I love to have a whole episode on
• 31:35
  Speaker 2: geoengineering stuff because it is so tempting. What if there
• 31:37
  Speaker 2: was some way that we could all just keep doing
• 31:39
  Speaker 2: exactly what we're doing, but just like throw some stuff
• 31:42
  Speaker 2: in the sky to take care of it. But yeah,
• 31:44
  Speaker 2: I don't think we understand things well enough.
• 31:46
  Speaker 1: Yeah, but they did, and in the sixties they did
• 31:48
  Speaker 1: it for Hurricane Esther and Hurricane Bulah, Hurricane Debbie, and
• 31:52
  Speaker 1: then Hurricane Ginger in nineteen seventy one. I wasn't able
• 31:55
  Speaker 1: to find more recent experiments. I don't know if those
• 31:57
  Speaker 1: are like still classified or whatever, but it's definitely something
• 32:00
  Speaker 1: people tried. Nobody's ever tried a nuke a hurricane as
• 32:03
  Speaker 1: far as I'm aware, which I'm grateful for. Though I
• 32:06
  Speaker 1: know that our president elect it's an idea that he
• 32:08
  Speaker 1: bounced around within his previous administration.
• 32:11
  Speaker 2: Well, I hope he listens to our podcast and we
• 32:14
  Speaker 2: can help out in that way.
• 32:15
  Speaker 1: I also remember seeing videos during some recent hurricane in
• 32:18
  Speaker 1: Florida of people shooting the hurricane. It seems like, I
• 32:22
  Speaker 1: get what you're expressing your frustration and this is the
• 32:25
  Speaker 1: only tool you have, But like, you don't want the
• 32:28
  Speaker 1: hurricane picking up those bullets and throwing them at high
• 32:30
  Speaker 1: speeds at anything. So don't shoot hurricanes people with nukes
• 32:34
  Speaker 1: or with bullets or really anything. Just get out of there.
• 32:37
  Speaker 3: Yeah, don't contribute to the problem.
• 32:39
  Speaker 1: Just leave.
• 32:40
  Speaker 2: That's sound advice there. So let's see what Margie thinks
• 32:44
  Speaker 2: of our sound advice and see if she felt like
• 32:46
  Speaker 2: this was a good answer.
• 32:48
  Speaker 1: Maybe we can convince her to slowly slide her finger
• 32:51
  Speaker 1: off of that big red button.
• 32:54
  Speaker 2: I wonder how much power Margie has, Sparis Margie. All right, Well,
• 32:59
  Speaker 2: here Margie's response, and then we'll take a break.
• 33:02
  Speaker 6: Wow, I'm a little surprised that it would just reform
• 33:05
  Speaker 6: after a blast. But let's say a nuke was shot
• 33:11
  Speaker 6: off in a hurricane in the middle of the ocean
• 33:13
  Speaker 6: and then it started spreading radiation.
• 33:15
  Speaker 1: All over the place.
• 33:17
  Speaker 6: Would it still be spreading radiation when it came ashore.
• 33:22
  Speaker 1: Very glad we were able to answer your question, Margie,
• 33:24
  Speaker 1: And that's a great follow up question. Yeah, it would
• 33:27
  Speaker 1: be very bad to release a lot of radiation into
• 33:30
  Speaker 1: a hurricane. The sort of long range danger from a
• 33:33
  Speaker 1: bomb going off is exactly having high winds which spread
• 33:37
  Speaker 1: those radiactive materials around, and so dropping one into a
• 33:41
  Speaker 1: hurricane it's basically the worst case scenario for containing that radiation.
• 33:45
  Speaker 1: So yeah, the winds in the water would spread that
• 33:47
  Speaker 1: radiation really far and cause a lot of damage. Again,
• 33:51
  Speaker 1: not a good idea. Please don't drop a bomb into
• 33:54
  Speaker 1: a hurricane.
• 34:15
  Speaker 2: So Our next question is from Kevin, So here we go.
• 34:20
  Speaker 7: This is a Kevin from Shoay, China, and I'll have
• 34:22
  Speaker 7: a question about philosophy. If a photon turns into the
• 34:26
  Speaker 7: electron and a positron, and the electron and positron and
• 34:30
  Speaker 7: wiolates into another photon, are the two photons exactly the same?
• 34:35
  Speaker 7: If they are the same, how can the photon appear
• 34:38
  Speaker 7: and disappear out of the air. And if they are
• 34:41
  Speaker 7: the same, is there a point when the first becomes
• 34:44
  Speaker 7: a second?
• 34:45
  Speaker 1: Ooh, thank you Kevin for asking such a fun physics
• 34:48
  Speaker 1: slash philosophy question.
• 34:50
  Speaker 2: Totally love this one, and I absolutely love hearing that
• 34:53
  Speaker 2: we have international listeners. This totally made my day. And
• 34:56
  Speaker 2: Daniel is clearly the right guy to answer your question.
• 34:59
  Speaker 2: So what's happening Daniel?
• 35:00
  Speaker 1: So what's going on here is that photons, when they
• 35:03
  Speaker 1: fly through space, you might just imagine like, hey, it's
• 35:06
  Speaker 1: a little packet of energy. It wiggles through space. That's it, right,
• 35:10
  Speaker 1: But we also talk about photons doing other stuff, like
• 35:12
  Speaker 1: photons can fly along and then we say sometimes they
• 35:15
  Speaker 1: can turn into a pair of particles called this conversion.
• 35:19
  Speaker 1: Like a photon is flying along and it turns into
• 35:21
  Speaker 1: an electron and a positron, two particles, so maintaining the
• 35:25
  Speaker 1: overall charge of zero, and then those particles can annihilate,
• 35:29
  Speaker 1: they can turn right back into a photon. So you
• 35:32
  Speaker 1: can imagine like either just a photon flying along which
• 35:34
  Speaker 1: turns into like a little loop of particles and then
• 35:37
  Speaker 1: turns back into a photon. And Kevin is asking, like,
• 35:40
  Speaker 1: what does that mean about the photon? Is that the
• 35:43
  Speaker 1: same photon that comes out after this particle loop or
• 35:48
  Speaker 1: is it not? And if it's not, then like, exactly
• 35:50
  Speaker 1: when does the new photon get born?
• 35:53
  Speaker 2: So is this philosophically the same as the transporter problem.
• 35:57
  Speaker 1: It's actually very similar to the transporter and it touches
• 36:01
  Speaker 1: on you know, what do you mean by this photon?
• 36:03
  Speaker 1: And how do you kill a photon? And all sorts
• 36:06
  Speaker 1: of stuff, and because in the end, these are quantum processes, right,
• 36:08
  Speaker 1: And the transporter problem in the end comes down to
• 36:11
  Speaker 1: like any time an object moves from place to place,
• 36:14
  Speaker 1: it's equivalent to making a copy of it and destroying
• 36:17
  Speaker 1: the old one, especially if we're all just ripples in
• 36:19
  Speaker 1: quantum fields, it's just your information sliding along. And so
• 36:23
  Speaker 1: basically every moment in your life. You're being transported through
• 36:27
  Speaker 1: space and time the same way a teleporter works, just
• 36:30
  Speaker 1: smaller distances. And so yeah, does that matter? Are you
• 36:33
  Speaker 1: being killed every instant and being recreated some other place?
• 36:37
  Speaker 1: What does that mean about being killed? I don't know anyway,
• 36:39
  Speaker 1: it's a big rabbit hole of philosophy. But here we're
• 36:42
  Speaker 1: focusing on a single photon.
• 36:43
  Speaker 2: Okay, so you're not going to answer that question for
• 36:45
  Speaker 2: us by the end of this answer. What do we
• 36:48
  Speaker 2: mean then by same If it's the same photon, what
• 36:51
  Speaker 2: would that mean?
• 36:52
  Speaker 1: Yeah, so there's two issues here we have to grapple
• 36:54
  Speaker 1: with if we're going to think about what this means,
• 36:56
  Speaker 1: and that's one of them. And the short answer, the
• 36:58
  Speaker 1: big picture answer to this question is that there is
• 37:00
  Speaker 1: no good answer to this question because the picture that
• 37:04
  Speaker 1: I just described, and that Kevin probably has this head
• 37:06
  Speaker 1: and a lot of people think about for photons, it's
• 37:08
  Speaker 1: a cartoon picture. It's not like our microphysical explanation for
• 37:13
  Speaker 1: what's really happening. Like you know, in biology, you can
• 37:16
  Speaker 1: have a microscopic explanation. You can say, oh, the reason
• 37:20
  Speaker 1: you're sick is a virus came in and attacked your
• 37:22
  Speaker 1: cell and to penetrated the cell wall, and you can
• 37:24
  Speaker 1: have this picture in your mind of these tiny things
• 37:26
  Speaker 1: happening that explain what we're experiencing on the big scale,
• 37:29
  Speaker 1: and that can be reality. So if you like zoom
• 37:32
  Speaker 1: in with a microscope, you can actually watch it. That's awesome, right,
• 37:35
  Speaker 1: And we try to do the same thing in physics,
• 37:37
  Speaker 1: provide a microscopic explanation for what we think is happening,
• 37:41
  Speaker 1: and that can be very satisfying, but it's sometimes a
• 37:44
  Speaker 1: cartoon and it's misleading because what's happening in the microscopic
• 37:47
  Speaker 1: scale is fundamentally, very very different from what's happening in
• 37:50
  Speaker 1: biology or in the classical scale. It's not like tiny
• 37:54
  Speaker 1: little balls or bouncing off each other or converting into particles.
• 37:57
  Speaker 1: You can't slow these things down and watch them like
• 37:59
  Speaker 1: a movie and get a version of the microscopic story.
• 38:03
  Speaker 1: So you know, what we mean by a photon isn't
• 38:05
  Speaker 1: just like a photon is flying through space, or a
• 38:08
  Speaker 1: photon flies through space and makes a particle loop. It's
• 38:10
  Speaker 1: sort of all of those things mixed together. So that's
• 38:13
  Speaker 1: why we have to identify what we mean by a
• 38:15
  Speaker 1: photon and what we mean by same.
• 38:17
  Speaker 2: So does this go back to our what is a
• 38:19
  Speaker 2: particle discussion? And do they work as waves or strings
• 38:24
  Speaker 2: or so? The question is hard to answer because we
• 38:27
  Speaker 2: don't even really know how to describe these things.
• 38:29
  Speaker 1: Yeah, exactly, and Kevin is picking out one aspect of
• 38:32
  Speaker 1: that cartoon, and really a photon is all of those things.
• 38:35
  Speaker 1: So let's start by talking about what a photon is,
• 38:37
  Speaker 1: and then we can dig into what do we mean
• 38:39
  Speaker 1: by the same photon. Okay, if you think about a photon,
• 38:42
  Speaker 1: it's just you're thinking about a single packet of light
• 38:44
  Speaker 1: that goes through space quantum mechanically. Kevin is right that
• 38:47
  Speaker 1: the photon could do that, but it could also convert
• 38:49
  Speaker 1: into these par of particles and go back. It could
• 38:51
  Speaker 1: also convert into those pair of particles, and then those
• 38:54
  Speaker 1: particles emit photons, which then turn into other stuff and
• 38:57
  Speaker 1: turn into other stuff. There's an infinite number of things
• 38:59
  Speaker 1: that a fon could do when it goes from A
• 39:02
  Speaker 1: to B, and each of those things comes with a probability.
• 39:06
  Speaker 1: And when we talk about the photon, we don't mean
• 39:09
  Speaker 1: one of those particles in one of those stories. What
• 39:12
  Speaker 1: we really mean is that whole bundle. We mean the
• 39:15
  Speaker 1: whole thing all mixed together because we don't know what's happening,
• 39:18
  Speaker 1: and there is no what's really happening the photon. The
• 39:21
  Speaker 1: thing we think about, the thing we should identify with
• 39:23
  Speaker 1: is all of those possibilities, not any individual one of
• 39:27
  Speaker 1: them or any part of them.
• 39:28
  Speaker 2: So when we were doing the what is a Particle episode,
• 39:31
  Speaker 2: we talked about how you don't explain the wave theory
• 39:35
  Speaker 2: of how you describe particles until grad school. And so
• 39:39
  Speaker 2: this question is making me wonder how the fact that
• 39:43
  Speaker 2: we are all taught to think about these as like
• 39:45
  Speaker 2: little points that are moving around, how much does that
• 39:49
  Speaker 2: inhibit all of our abilities to think about these things?
• 39:52
  Speaker 2: Like should we be changing the way we address this
• 39:54
  Speaker 2: in high school? I know it's much harder to explain
• 39:58
  Speaker 2: it as a wave, but it's wrong. It sounds like
• 40:00
  Speaker 2: the way we explain it.
• 40:02
  Speaker 1: Yeah, quantum field theory in kindergarten. That's what I think. No,
• 40:06
  Speaker 1: it's a great question, and I think you're right, And
• 40:08
  Speaker 1: you see it in physics students as they learn this stuff,
• 40:11
  Speaker 1: you teach them to think about particles and then you're like, actually,
• 40:14
  Speaker 1: all your intuition is wrong. You have to unpack that
• 40:16
  Speaker 1: and learn this whole other thing. And you know, I'm
• 40:19
  Speaker 1: very interested in physics education. We have these conversations like
• 40:21
  Speaker 1: what is the right order to teach people in, But
• 40:24
  Speaker 1: there's sort of this canonical order that everybody uses that
• 40:26
  Speaker 1: sort of follows the historical development. It's like, we thought this,
• 40:30
  Speaker 1: then we thought that, then we thought that, And as
• 40:33
  Speaker 1: you move through your physics education, you sort of catch
• 40:35
  Speaker 1: up to modernity. And I think it is important to
• 40:38
  Speaker 1: understand where these ideas came from, like why people thought
• 40:41
  Speaker 1: this and why people thought that, because just like with
• 40:44
  Speaker 1: the names of hurricane and typhoon, there's a lot of
• 40:47
  Speaker 1: like weird, patchy stuff that doesn't really make sense unless
• 40:50
  Speaker 1: you understand the history. So you kind of got to
• 40:52
  Speaker 1: teach people the current ideas, but you also want to
• 40:54
  Speaker 1: give them a tour of how we got here so
• 40:57
  Speaker 1: they can understand why some of it seems weird and ugly.
• 41:02
  Speaker 1: So I don't know the right answer to your question.
• 41:04
  Speaker 2: Okay, I mean I see no reason why we couldn't
• 41:06
  Speaker 2: start with here's the wave theories and string theories of
• 41:10
  Speaker 2: particles and then after be like, well, here's the history.
• 41:13
  Speaker 2: Let's talk about how we got here m hm, so
• 41:15
  Speaker 2: that people would be less confused. But anyway, I'm not
• 41:18
  Speaker 2: a physics educator, but I guess I kind of am.
• 41:20
  Speaker 1: Yeah, I guess that we have opinions at least. So
• 41:23
  Speaker 1: in that episode about a particle, we also talked about
• 41:25
  Speaker 1: how you can think about particles, as you know, little
• 41:27
  Speaker 1: dots flying through space turning into other stuff. You could
• 41:30
  Speaker 1: also think of them as fields. Right, instead of imagining
• 41:34
  Speaker 1: a bit of stuff, imagine a field feeling the universe,
• 41:37
  Speaker 1: and particles are ripples in those fields, and those two
• 41:40
  Speaker 1: things are actually mathematically equivalent. You can think about everything
• 41:43
  Speaker 1: as particles and they pull on pushing each other by
• 41:47
  Speaker 1: passing other particles between them, or you can think of
• 41:50
  Speaker 1: just fields and energy is flowing between the fields. And
• 41:53
  Speaker 1: I think the field's picture is really helpful to think
• 41:55
  Speaker 1: about for this question, because what we're talking about is
• 41:58
  Speaker 1: not just one part of it's a particle interacting with
• 42:01
  Speaker 1: another particle, right, Photons turning into electrons and back and forth.
• 42:05
  Speaker 1: And in the field picture, that's kind of beautiful. What
• 42:08
  Speaker 1: we see there is two fields interacting like a photon
• 42:11
  Speaker 1: as it flies through the universe is not just a
• 42:14
  Speaker 1: ripple in the electromagnetic field, as we say, because the
• 42:17
  Speaker 1: electromagnetic field affects the electron field, and vice versa. So
• 42:21
  Speaker 1: when you say in the particle picture, okay, a photon
• 42:24
  Speaker 1: is flying along and you can turn into an electron
• 42:26
  Speaker 1: and positron and go back in the field picture, that's
• 42:29
  Speaker 1: the same thing as saying energy can slash from the
• 42:31
  Speaker 1: photon field to the electron field and back. And what's
• 42:35
  Speaker 1: really happening is not that there is an electron there
• 42:37
  Speaker 1: or there is a photon there. But the thing we
• 42:39
  Speaker 1: call a photon is this interaction between the two fields.
• 42:43
  Speaker 1: So that's the problem with putting your finger on like
• 42:45
  Speaker 1: is it the same photon? Well, what do you mean
• 42:47
  Speaker 1: by a photon? Do you mean just the electromagnetic field,
• 42:50
  Speaker 1: like theoretically pure concept, or do you mean the thing
• 42:53
  Speaker 1: we see in the universe, which is like buzzing interaction
• 42:56
  Speaker 1: between photons and electrons or the photon and electron fields.
• 42:59
  Speaker 1: That's really what a photon is. A photon that hits
• 43:01
  Speaker 1: your eye from Andromeda has interacted with the electron field
• 43:04
  Speaker 1: all the way between there and here.
• 43:06
  Speaker 2: Okay, can we give a two sentence answer to summarize.
• 43:10
  Speaker 1: Yeah, So what is a photon? A photon, I think
• 43:12
  Speaker 1: is all the possible things that could happen between A
• 43:15
  Speaker 1: and B, and when the photon is created and the
• 43:16
  Speaker 1: photon is observed, you can't really dig into what happens
• 43:20
  Speaker 1: in between because there are multiple possibilities and all of
• 43:23
  Speaker 1: them play a role. Right. So now, so Kevin's question,
• 43:26
  Speaker 1: what do we mean by the same photon? Well, you know,
• 43:30
  Speaker 1: I think that you can't really think about those individual
• 43:32
  Speaker 1: photons and say is it the same? And if you tried,
• 43:35
  Speaker 1: you get yourself into all sorts of other hairy misses
• 43:38
  Speaker 1: that we touched on earlier, Like think about an individual
• 43:41
  Speaker 1: photon not just flying through space, but like bouncing off
• 43:43
  Speaker 1: of a mirror. What happens when a photon bounces off
• 43:46
  Speaker 1: of a mirror, Well, we think it's absorbed and re
• 43:49
  Speaker 1: emitted at the right angle. Is that the same photon? Well,
• 43:52
  Speaker 1: you know, it's like if you shine a light in
• 43:54
  Speaker 1: the mirror, the light hits your eyes. We think of
• 43:56
  Speaker 1: the light as bouncing off and hitting your eyes, but
• 43:58
  Speaker 1: it's been reabsorbed and re emitted. Is that the same?
• 44:01
  Speaker 1: If you say that's not the same, that means that
• 44:03
  Speaker 1: every time particles interact, they're no longer the same particle.
• 44:07
  Speaker 1: But particles are interacting constantly all the time. You are
• 44:10
  Speaker 1: a huge pile of particles interacting, which means that you
• 44:12
  Speaker 1: were not the same you were a millisecond ago. So
• 44:15
  Speaker 1: that leads nowhere. If you say that particle interaction means
• 44:18
  Speaker 1: they're not the same particle anymore, then you have no
• 44:20
  Speaker 1: useful meaning for the word same. Then you have to say, well,
• 44:24
  Speaker 1: then maybe a particle is the same if it's like
• 44:27
  Speaker 1: mostly unchanged. You shot the photon at the wall, it
• 44:30
  Speaker 1: bounced off, and it's mostly the same energy and the
• 44:32
  Speaker 1: same frequency and all that kind of stuff. So it's
• 44:34
  Speaker 1: mostly the same photon even though it's interacted. So from
• 44:37
  Speaker 1: that point of view, then the answer to Kevin's question
• 44:39
  Speaker 1: would be like, yeah, it's the same photon. And I
• 44:41
  Speaker 1: think philosophically unpeeling it. It's a big blob of energy.
• 44:45
  Speaker 1: It's flowing through the universe. It's oscillating between the different fields.
• 44:48
  Speaker 1: It doesn't really matter. That has a chance to be
• 44:50
  Speaker 1: an electron here and a chance to be a photon there.
• 44:52
  Speaker 1: It's the same blob of energy that was sent to
• 44:54
  Speaker 1: you from Andromeda. So I think it's the same photon.
• 44:57
  Speaker 1: So does that make sense to you, Kelly? What do
• 44:59
  Speaker 1: you think.
• 44:59
  Speaker 2: Yes, all right, that makes sense to me. Here, let
• 45:02
  Speaker 2: me see if I can explain it.
• 45:03
  Speaker 3: Okay.
• 45:04
  Speaker 2: So the reason that it's a complicated question is because
• 45:08
  Speaker 2: it's hard to think of a particle as like a
• 45:10
  Speaker 2: point in space. They're like packets of energy that are
• 45:13
  Speaker 2: interacting with other packets of energy, and they can be
• 45:16
  Speaker 2: hard to describe.
• 45:17
  Speaker 3: You know, they're.
• 45:17
  Speaker 2: Interacting like they're a wave, like they're a string, but
• 45:20
  Speaker 2: they're just sort of things that are interacting with other things,
• 45:23
  Speaker 2: and that's what they're doing all the time. And so
• 45:26
  Speaker 2: to try to figure out is this the exact same
• 45:28
  Speaker 2: thing when part of how we understand it is that
• 45:31
  Speaker 2: these things are changing and interacting over.
• 45:32
  Speaker 1: Time, it makes it an awkward question.
• 45:36
  Speaker 3: Yeah, yeah, is that an okay way to summarize it?
• 45:38
  Speaker 1: Yeah, I think that's great. I'm giving you a PhD
• 45:41
  Speaker 1: in Internet physics right now?
• 45:42
  Speaker 2: Yes, right, okay, but grades are really important to me,
• 45:46
  Speaker 2: and I haven't gotten one in like fifteen years, So
• 45:49
  Speaker 2: can you tell me?
• 45:50
  Speaker 3: And I got an A. Actually I kind of feel
• 45:51
  Speaker 3: like that was more like a B answer.
• 45:53
  Speaker 1: No, that was a solid A answer. Yeah, And now
• 45:56
  Speaker 1: I'm curious what Kevin thinks about our answer. So in
• 45:59
  Speaker 1: a moment, you'll hear Kevin giving us a grade on
• 46:02
  Speaker 1: our physics answers to his philosophy question.
• 46:05
  Speaker 7: Hi Janyan Kelly, thank you for answering my question. I
• 46:09
  Speaker 7: think you mean that a photon is quantum mechanical, so
• 46:13
  Speaker 7: it's a mix of the probabilities of all the possible
• 46:16
  Speaker 7: things that can happen. Also, depending on the meaning of saying,
• 46:21
  Speaker 7: the photon is the same and not the same at
• 46:23
  Speaker 7: the same time, which is mind boggling. I totally love
• 46:27
  Speaker 7: these kinds of answers.
• 46:29
  Speaker 2: Thank you so much to Chris, Margie and Kevin for
• 46:32
  Speaker 2: their amazing questions today. We had so much fun thinking
• 46:35
  Speaker 2: about these problems. And if you have a question that
• 46:37
  Speaker 2: you would like to share with us, please write us
• 46:39
  Speaker 2: at questions at Daniel and Kelly dot org.
• 46:42
  Speaker 3: We would love to hear from you.
• 46:44
  Speaker 1: We would and your friends will be so impressed to
• 46:46
  Speaker 1: hear your voice on a podcast, especially a nerdy podcast
• 46:50
  Speaker 1: like ours.
• 46:51
  Speaker 3: Huzza.
• 46:51
  Speaker 1: Thanks everyone, keep asking questions and stay curious.
• 46:54
  Speaker 3: See you later.
• 47:02
  Speaker 2: Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio.
• 47:06
  Speaker 3: We would love to hear from you, We really would.
• 47:08
  Speaker 1: We want to know what questions you have about this
• 47:11
  Speaker 1: extraordinary universe.
• 47:13
  Speaker 2: We want to know your thoughts on recent shows, suggestions
• 47:16
  Speaker 2: for future shows.
• 47:17
  Speaker 3: If you contact us, we will get back to you.
• 47:20
  Speaker 1: We really mean it. We answer every message. Email us
• 47:23
  Speaker 1: at Questions at Danielankelly dot org, or.
• 47:26
  Speaker 3: You can find us on social media.
• 47:28
  Speaker 2: We have accounts on x, Instagram, Blue Sky and on
• 47:32
  Speaker 2: all of those platforms.
• 47:33
  Speaker 3: You can find us at d and kuniverse.
• 47:36
  Speaker 1: Don't be shy right to us