Listener Questions #20

Daniel and Kelly answer questions from listeners about aliens, archaea and the speed of light. See omnystudio.com/listener https://omnystudio.com/listener for privacy information.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Daniel Whiteson?

  This is an iHeart Podcast. Guaranteed Human.

• 0:04Speaker 01

  OnDeck is built to back small businesses like yours. Whether you're buying equipment, expanding your team, or bridging cash flow gaps, OnDeck's loans up to $400,000 help make it happen fast. Rated A+ by the Better Business Bureau and earning thousands of five-star Trust Pilot Reviews, OnDeck delivers funding you can count on. Apply in minutes at ondeck.com. Depending on certain loan attributes, your business loan may be issued by OnDeck or Celtic Bank. OnDeck does not lend in North Dakota. All loans and amounts subject to lender approval. If you're a custodial supervisor at a local high school, you know that cleanliness is key and that the best place to get cleaning supplies is from Grainger. Grainger helps you stay fully stocked on the products you trust, from paper towels and disinfectants to floor scrubbers.

• 0:49Speaker 02

  Plus, you can rely on Grainger for easy reordering, so you never run out of what you need. Call 1-800-GRAINGER, click Grainger.com, or just stop by. Grainger, for the ones who get it done.

• 1:04Speaker 02

  Hey, I'm Niall Rogers. This fall, I'll be driving across the country, meeting some of today's coolest and most fascinating artists. We'll explore the stories before the moments that changed everything. Because every musician remembers the moment where it all began. Experience Before the Moment, a Lincoln Original Series on the iHeart Radio app, YouTube, or wherever you get your podcasts.

• 1:37Daniel Whiteson?

  Quick note before today's episode to let you know about my new book, Do Aliens Speak Physics?, which is available for preorder now and can be at your house on November 4th. It's all about my favorite scenario, aliens arriving on Earth, and what it would be like to try to talk to them about physics. Is that really possible? We don't know, but the book is a fun exploration of the potential challenges. If you've enjoyed my science outreach, this is a nice way to support me. Check it out at www.alianspeakphysics.com. Okay, on to today's episode.

• 2:18Daniel Whiteson?

  I like to think about alien life, but where are they all if aliens are so rife?

• 2:25Kelly Weinersmith?

  If you don't metabolize and reproduce, then science says you're dead. Does a recently discovered critter turn this definition on its head?

• 2:34Daniel Whiteson?

  A curious listener wants to know, what would the universe be like if light were very slow?

• 2:40Kelly Weinersmith?

  Whatever questions keep you up at night, Daniel and Kelly's answers will make it right.

• 2:45Daniel Whiteson?

  Welcome to Daniel and Kelly's Extraordinary Universe.

• 3:02Kelly Weinersmith?

  Hello, I'm Kelly Wiener-Smith. I study parasites and space, and I am excited that we're talking about aliens today. And the reason I'm excited about that is because I'm really excited about this book that's coming out called Do Aliens Speak Physics?

• 3:14Daniel Whiteson?

  Oh, my gosh, for a moment, I thought you were going to tell me about another book about aliens. So I was going to scoop mine. Oh, no, my nightmare.

• 3:23Daniel Whiteson?

  Hi, I'm Daniel. I'm a particle physicist, and I do love thinking about aliens because I worry that the way we do science is somehow infected with our humanity. And there's somebody out there getting deeper at the truth of the matter.

• 3:36Kelly Weinersmith?

  Oh, infected by our humanity. That is a surprisingly negative view from you, I think.

• 3:42Daniel Whiteson?

  I was trying to speak biology, you know, like, you know, I was trying to use some sort of parasitical language there.

• 3:47Kelly Weinersmith?

  I think you're implying that we're all pessimists and negative, but you know, I am. So that's, that's fine with me.

• 3:53Daniel Whiteson?

  Well, thank you for bringing up my book, which is coming out in November. It's called Do Aliens Speak Physics? And you can get it all fine, booksellers and probably several others. And you write that it's a little bit pessimistic because the book is in response to my concern that we were sort of putting ourselves at the center of the universal intellectual stage by saying, like, everything we've discovered is true, it's real, you know, it's universal that other scientists around the galaxy will find the same thing. To me, that's Acts a little bit of like the earth is the center of the solar system or the universe, you know, or we are important somehow on a cosmic stage. And so I just wanted to ask like, well, is that really true? Are there ways that our humanity has affected our science?

• 4:37Daniel Whiteson?

  And so that's what the book is about is would aliens do physics differently? And how could we know?

• 4:42Kelly Weinersmith?

  And at a future date, we will have a whole episode talking about that question and what you learned while you were researching that problem. But today I wanted to ask you, what is your favorite part of writing a book?

• 4:53Daniel Whiteson?

  Favorite part of writing a book? Ooh, it's definitely not coming up with the title. I don't know why, but that's so frustrating. It's so hard to capture everything about the book in a few words. You know, you have to like meet the reader where they are, get them interested, tell them a little bit about the book. Also, it should be like clever in some way. So, boy, that is really tough. And you and I have had lots of conversations about titles. It's tricky. It's tricky. I think my favorite two parts of writing a book are having the initial idea. Like, it's always fun to come up with a new idea for a project, you know, as an academic, like, new projects are shiny and fun. And current projects like, ugh, man, I just gotta get that thing finished.

• 5:35Kelly Weinersmith?

  Gotta get it out the door.

• 5:36Daniel Whiteson?

  But also the research, like, I love digging in deep and reading a bunch of papers. And I wonder sometimes, like, why didn't I just do this before? But for some reason, like, having a reason to dig in and to read up about it and to learn about it, if that excuse is like, I'm writing a book about this, or I'm doing research for a listener or something, it's easier to do, it's more fun, it feels like you're allowed to do it instead of you just goofing off and reading philosophy papers.

• 6:01Kelly Weinersmith?

  I absolutely agree with you. And that is also why I love our listener question segment so much, is that we, whenever a question comes across my inbox where I'm like, oh, I want to know more about that, then I'm like, that immediately goes in the listener questions pile. And then while I'm researching it, I don't feel like I'm slacking off. I'm doing my quote unquote work. And it's awesome.

• 6:22Daniel Whiteson?

  There you go. And so is that also your favorite part of writing a book? The deep research dive?

• 6:27Kelly Weinersmith?

  The two things I hate the most, I always write the title last because I hate it. I agree. And then I hate the part where I'm supposed To promote the book and ask people for favors. And that's my least favorite part, but um, but it's part of the job. But no, my favorite is is just getting to do the research and learning about new stuff, which is why I so rarely write books about things I already know about. Cause I'd rather have an excuse to read about something new and like going through space law textbooks. On the one hand, there were days where I'm like, why do I enjoy this so much? Do I enjoy this? I'm not sure. I'm on the fence. Then at the end of the day, I'd be like, oh my gosh, I just learned about like the laws governing the cosmos. And that's pretty cool. And and also how they are inadequate.

• 7:12Kelly Weinersmith?

  And so, yeah, it's a fun research topic.

• 7:15Daniel Whiteson?

  I think it's also really fun to discover the things that are interesting to you. And you've done a day of reading and then you come to dinner with the family and you're like, excited to talk about some nerdy detail you read about that was really cool, or some new critter, or some crazy idea you thought about and had never considered before. It shows you like which parts of the universe inspire you and connect with you. And and that's what I love about science, that there's just so much like that we just find cool. I mean, it's an emotional response, right? And and this is actually one of the things I'm curious about aliens. Like, do aliens have the same emotional reaction to the mysteries of the universe? Are they curious? Do they care? Right? Is that human or is that universal? That's like a very basic question. We don't know the answer to.

• 7:58Daniel Whiteson?

  But for me, it's one of my favorite things about being human.

• 8:01Kelly Weinersmith?

  Yeah, yeah. Well, and what I want to know is do they care about us? Which leads us nicely into our first question from a listener. So let's go ahead and hear that question.

• 8:10Speaker 04

  Hi, I'd love to hear your thoughts about the Fermi paradox. Is it really a paradox? While I think the theories about the great filter, like if there's some big thing that always prevents beings from reaching interstellar travel. I think that's a really interesting thought experiment. But in general, I've never really seen the Fermi paradox as a true paradox, just due to how big the universe is and how spread out everything is. Like, the odds of two kinds of intelligent life somehow intercepting just feels too unlikely. Not to mention the significant time delay. Like, if alien friends from 30,000 light-years away, which is, you know,

• 8:54Speaker 04

  relatively our neighbors on the scale of the universe, if they sent out a signal right now, or even 100 years ago, or 1,000 years ago, we're not getting that signal for tens of thousands of years still. Am I right to think that this isn't really a paradox? Or am I misunderstanding something, or not thinking about it correctly? I'd be happy to be proved wrong here, so I'm looking forward to your answer. Thank you.

• 9:20Kelly Weinersmith?

  Yay! All right, Daniel, so tell us about the Fermi paradox, which in an earlier version of the book that I read, explains the Fermi paradox. So if anyone wants to dive deeper, they should check out your book. I assume it's still in there.

• 9:32Daniel Whiteson?

  Yeah, so the Fermi paradox, quickly, is essentially asking, hey, the galaxy is filled with stars and planets. There are hundreds of billions of stars, and we now know that most of them have planets, and many planets. And so there are tens of billions at least of rocky planets around stars, which are a lot of places for aliens to form, and to learn, and to develop technology, and to send us messages, or to come visit us. And space is big, but the Milky Way is not that big compared to its age. I mean, the Milky Way is like 100,000 light-years across, so it would take a long time to traverse it. But, you know, a long time is a few million years.

• 10:15Daniel Whiteson?

  And the Milky Way is billions and billions of years old. We think more than 10 billion years old. And we've been here for several billion. Of course, humanity is younger than that. But you can imagine scenarios where aliens have traversed the galaxy and left relics, or filled it with messages. It's not that difficult to imagine. And so the question is, where is everybody? Why haven't we been contacted? By aliens or visited by aliens. So this famously and probably apocryphally is something Fermi said at lunch at Los Alamos about 50 or 60 years ago, and people have been wondering about since.

• 10:52Kelly Weinersmith?

  But he did at some point make an equation, right? So it maybe started as a lunch conversation, but where did the equation come from?

• 10:58Daniel Whiteson?

  So there's an equation by Drake, that's the Drake equation, that tries to calculate how many aliens should be contacting us. And it's pretty simple as equations go. It's just a multiplication of a bunch of factors. But there's actually a lot you can learn just from the structure of the equation. So the equation is like the number of stars times the fraction that have planets, times the fraction that might have life, times the fraction that might be civilized, times a fraction, you know, that developed technology. I don't remember exactly the structure of the terms, but the fact that they're multiplied together is important because that emphasizes that to hear from aliens, all of those factors have to be non-zero. Like, it doesn't matter if the universe is filled with life, if none of it is technological, right?

• 11:42Daniel Whiteson?

  If there's life everywhere, but it's all just like sheets of algae or heaps of microbes, then we're not hearing from anybody. We're not getting visited. Or if they become intelligent, but none of them ever developed technology, for example. So all of those things have to work. All of those factors have to be non-zero for us to hear. And we know that the number of planets is large, number of stars is large. We don't know, for example, what is the fraction of those planets that have life on them? We know there's one, ours, but it could be the only one. And the denominator is large. So it could be that the fraction of planets with life on them is like one over a gazillion, in which case we're the only life in the Milky Way. Or it could be 50%, you know, or 10%, so that the Milky Way is filled with life.

• 12:27Daniel Whiteson?

  We just don't know so many of these fractions.

• 12:30Kelly Weinersmith?

  So Julie asked something about the great filter. What does the great filter mean?

• 12:35Daniel Whiteson?

  Yeah, the great filter suggests that there might be life everywhere, and there might even be intelligent and civilized life everywhere, but it might not just last very long. That civilizations might essentially burn themselves out. And there's a few ways that this could happen. You know, civilizations might become technological and then develop the means to kill themselves and end up basically nuking each other. And that might be like a trend that happens, not in the sense that it's inevitable, or that it has to happen necessarily. You could never prove that. But it might be something that's fairly common. Or it could be that civilizations pollute their atmospheres, right? Or cause global warming, or in some other way, end up killing themselves off.

• 13:17Daniel Whiteson?

  So that's the idea of the great filter to explain the lack of contact or observation of aliens by saying that life is very short-lived. And remember, time is very, very deep. And so even if there have been a thousand civilizations in the Milky Way, if each of them only lasted a few thousand years, like the length of human civilization so far, then in the space of billions of years, it's very unlikely that we would hear from them now, or that we would happen to be alive at the right moment to receive messages from them.

• 13:45Kelly Weinersmith?

  Okay, that's kind of a bummer, which is right up my alley. So what do you think the answer is?

• 13:53Daniel Whiteson?

  So now we have to depart from well-founded science, right? And just speculate, because we just don't know. And everything we're doing, I've heard a lot of, you know, semi-scientific analyses of these things, but in the end, we're always extrapolating from one example. And you can learn things from one example. You can say like, "Life didn't take very long to develop on Earth, so maybe it's not unusual." Whereas intelligence did take a long time to develop on Earth, so maybe that is weird and rare. Like, you can do those analyses, but in the end, it's just one, you know? It's like, if you roll a die with a million sides on it, and you get a six, you're like, hmm, that's kind of a weird number, but you'd like another roll, right? You'd like more measurements before you decide if the die is fair or not.

• 14:35Daniel Whiteson?

  So, you know, everything we're going to talk about now is non-scientific extrapolation, and really just wish fulfillment. But that doesn't mean we can't do it, you know? And so my sense is that we're not great at imagining the scope of possibilities. Right? We tend to do perturbation theory, basically take our example and tweak it a little bit. And you know, that's what people did for Star Trek, like, you know, Klingons are humans with weird foreheads. Our Vulcans are humans with weird ears, right? We tend to start from our example and then go off in some direction. But aliens are not limited by that. They don't have to start from humanity and then tweak it. They can start from a completely different place. And because we have only one example, it's very likely that we're not considering the full landscape.

• 15:19Daniel Whiteson?

  And so the short answer is I expect aliens are going to be way more alien than we can even imagine in ways that would prevent them from wanting to contact us or from having what we would recognize as civilization or technology, or to send us messages that we don't even interpret or notice or understand to be alien. So my favorite explanation for the Fermi paradox is in that direction, that aliens are too alien.

• 15:47Kelly Weinersmith?

  Interesting. So Aric Kirschenbaum wrote Zoologist's Guide to the Galaxy.

• 15:51Daniel Whiteson?

  Great book.

• 15:52Kelly Weinersmith?

  Great book. And, you know, one of the arguments there is that you might expect to find organisms to have happened upon some of the same solutions that we see here on Earth, because probably the principles of natural selection act the same no matter where you are. And there are similar pressures and a lot of environmental pressures in a lot of different places. And so why, well, give me some examples then of what you're thinking and like, why you expect things will be so different.

• 16:18Daniel Whiteson?

  So first of all, I really liked that book. I recommend everyone read it. I had a lot of fun reading it and I actually chatted with him on the previous podcast about it. So folks can check that out. But I think that that line of argument is a little dangerous. You know, it's sort of like post facto rationalization. It's like saying, Like, it's easy to convince yourself that humans are a natural endpoint to evolution. Like, well, boy, bipedalism makes a lot of sense. Having two eyes makes a lot of sense. It makes sense to have a nose on your face and you could get yourself towards arguing like, yeah, aliens are gonna look a lot like humans because we make sense. But what we don't know is how many other ways evolution could have gone, right? And arrived at other solutions that those folks would also say, gosh, it just makes sense

• 17:02Daniel Whiteson?

  to have a hand sticking out of your forehead, you know, or to have a transient anus or whatever. Fun. You could rationalize those things. It's sort of like counting coincidences, right? We're not good at thinking about the breadth of possibilities. And specifically, I think that our evolution, a lot of the arguments that he makes, you know, like, critters will eat other critters because predation is universal, depend on the environment that we've evolved in, you know, and some of the sort of fundamental economics of it. Like, imagine if instead of critters walking across a surface of a planet or even swimming in its ocean, what if we were life forms that existed in the atmosphere of a star? Right? We were like currents of plasma.

• 17:43Daniel Whiteson?

  And the distinction between alien bodies wasn't even that crisp, right? I think about where you define the edge of your body. Is it at your skin? No, because there's hair there. Okay, your hairs. But now you have like a weird fuzzy definition for like where it's Kelly and where it's not Kelly. And if you dig down and you're like really philosophical about it, it's not well-defined. Like, there's a fuzzy edge between Kelly and the universe. And we like to think of ourselves as a thing, a one thing that's distinct from the universe because it's important to us sort of like culturally and mentally. But what if we weren't? You know, if we were like flowed between each other and we like shared plasma or whatever, we would have a very different sort of relationship with the idea of identity.

• 18:26Daniel Whiteson?

  And that could change fundamentally what it's like to be a critter in that kind of, you know, evolutionary economics. That's just one example, you know? Or imagine if we evolved in a very different kind of situation, like a subsurface ocean. You know, we think that there might be oceans, even in our solar system, under Thick layers of ice. And so if you're some sort of like weird critter that flits around a completely dark ocean, you might evolve and then you might have no interest in the outer universe because you don't even know that it's there. And maybe you don't develop thumbs or technology or do anything interesting like that. And so there's lots of situations where aliens are just weirder than I think zoologists might imagine.

• 19:12Kelly Weinersmith?

  I don't know why you need to hone in on my people. But all right, I see your point. And I think that your imagination is why I enjoyed your science fiction so much.

• 19:22Daniel Whiteson?

  Thank you. I think the lesson here is that there are a lot of human patterns that we don't recognize our human patterns. And the best thing about meeting aliens will be discovering those things. We'll be understanding, oh, my gosh, we never even imagined that you didn't have to have X, Y, or Z for life. And I would tell you what X, Y, and Z were if I knew now, but I don't. Right. And so that's one of the reasons I had so much fun writing that book is like, thinking about the edges of our knowledge and where we might be making assumptions that we hadn't realized. And frankly, I think biologists are way ahead of physicists in this regard. You know, y'all have thought about like, hey, do we need water for life? Hmm, it might be possible to use ammonia. Do we need carbon for our chemistry? No, you could actually maybe use silicon. And that's been helpful because it's changed

• 20:05Daniel Whiteson?

  the way we look for life and imagine where it is. I think physicists are well behind because they all just assume that aliens will do physics the way that we do. And that's probably wrong.

• 20:16Kelly Weinersmith?

  On behalf of my community, I thank you for the compliment. All right, let's see what Julie thinks of your answer. And thank you to Julie for giving me the opportunity to talk about how great Daniel's book is.

• 20:29Speaker 04

  Hi, thanks for answering my question. I really like what you said about how the Milky Way isn't that big compared to its age. And there would maybe be relics out there that in theory, we'd be able to detect. I was kind of just thinking about how big the universe is without necessarily factoring in how old it is too. So I think I'm overall back on team paradox, but the explanation for the paradox could be many, many different things beyond just how far apart everything is, like all of the many different factors that you mentioned, and just how truly alien they could be. I think it's so fun to think about this stuff. So really enjoyed how you talked through it. Thanks again. Love the show.

• 21:18Speaker 05

  OnDeck is built to back small businesses like yours. Whether you're buying equipment, expanding your team, or bridging cash flow gaps, OnDeck's loans up to $400,000 make it happen fast. Rated A+ by the Better Business Bureau and earning thousands of five-star TrustPilot reviews, OnDeck delivers funding you can count on. Apply in minutes at ondeck.com. Depending on certain loan attributes, your business loan may be issued by OnDeck or Celtic Bank. OnDeck does not lend in North Dakota. All loans and amounts subject to lender approval.

• 21:46Speaker 02

  Hey, it's Niall Rogers, host of Before the Moment, a Lincoln original series. I'm driving across the country, meeting some of today's most fascinating artists. We're exploring the stories before the moment that changed everything. This week, I'm joined by my friend, John Ledge. What still makes you just sit down at the piano?

• 22:09Speaker 06

  If you sat down at 9:00 AM and then at noon, you had a full song that you recorded and put in your voice recorder or you recorded at your studio, you just created something brand new that didn't exist when you woke up. What a beautiful feeling it is. I'm always excited to write something new. I've been writing for Broadway, which has been a new challenge with new collaborators and amazing performers who are triple threats, who can sing and dance and act and do all these amazing things. And I want to keep feeling that. And so that means not resting on my laurels, going out there and continuing to create something new.

• 22:44Speaker 02

  Experience Before the Moment, a Lincoln original series on the iHeartRadio app, YouTube, or wherever you get your podcasts.

• 23:04Kelly Weinersmith?

  All right, so next up, we have a question from our Discord channel. And if you want to join us on Discord, and I really hope that you will, you just go to our website at danielandkelly.org and you can click the link to find our Discord group. And today's question is from Pip Darkat.

• 23:23Daniel Whiteson?

  What are you gonna do the day, Kelly, when somebody has a Discord handle that's not safe for podcasting?

• 23:29Kelly Weinersmith?

  Oh, I will ask our amazing audio engineer, Matt Kesselman, to bleep it for me.

• 23:34Speaker 01

  No promises.

• 23:36Kelly Weinersmith?

  I already have a plan.

• 23:39Kelly Weinersmith?

  Hey there, extraordinaries. It turns out that listener Pip Darkat from Discord wasn't able to get back to us in time for putting the audio together for this episode. So I'm gonna go ahead and read her question from the Discord. "Hi, Daniel and Kelly. I want to know more about Sukunarchaeum. I was reading a feed about how this organism is a missing link between life and not life. Would you consider this for an episode, Kelly?" Well, Pip Darkat, indeed I would. Here's your answer. Hope you're doing well.

• 24:15Daniel Whiteson?

  All right, so tell me about this question and how do we pronounce the name of this critter?

• 24:19Kelly Weinersmith?

  Oh, come on, man. You know I don't know the answer to that. You know that I am notoriously bad at pronouncing all of these names, so I'm gonna say it's Sukunarchaeum.

• 24:32Daniel Whiteson?

  Nice, that sounds plausible.

• 24:34Kelly Weinersmith?

  Because I said it fast. Yeah, that's why. That was the trick. And so, let's see, I'll jump ahead to why it's named that. So in Japanese mythology, there is a deity who is small, and the name is Sukuna. I'm sorry, the deity's full name is Sukunabikana. My apologies to all of Japanese culture. And so they took the first part of that deity's name, and because this critter is exceedingly small, in fact, we haven't even seen it with our eyes yet. We've only found its genome and sequenced it so far. They put that name in front, and then since it appears to be from the domain Archea, they named it Sukunarchaeum.

• 25:18Daniel Whiteson?

  Very cool.

• 25:18Kelly Weinersmith?

  Which rolls off the tongue whether it's correct or not. I like it.

• 25:21Daniel Whiteson?

  Archea is really fascinating. Tell us a little bit about Archea. I think a lot of people don't even know that it exists. What is Archea and why is it so weird and different?

• 25:30Kelly Weinersmith?

  Yeah, so it's incredible. And you know, I actually wonder if you know more about this from dinner table conversations with Katrina, so feel free to jump in.

• 25:36Daniel Whiteson?

  We do have the Tree of Life right in front of our dining room table, so Archea does come up sometimes.

• 25:42Kelly Weinersmith?

  Do you? Do you have like a painting of the Tree of Life in your kitchen?

• 25:46Daniel Whiteson?

  We have a big poster of it, yeah.

• 25:47Kelly Weinersmith?

  Oh, that's amazing. Amazing. I need that. And you know what I learned in this episode is that you won't find viruses on that tree.

• 25:54Daniel Whiteson?

  Yeah, that's true.

• 25:55Kelly Weinersmith?

  Which kind of makes sense, but also kind of makes me think of some evolutionary questions. But anyway, okay, way back in our evolutionary history, so very close to the base of that tree, you ended up getting three different domains. So you ended up with three splits. And so you get archaea, bacteria, and eukaryota. Eukaryota have membrane-bound organelles. So we are eukaryotes. We have these membrane-bound organelles. We called them orgonitos in a past episode, and I thought that was cute, and I'll never forget.

• 26:26Daniel Whiteson?

  I think it's amazing that eukaryotes basically have like a little clump of ocean, right? Like, we think life started in the ocean, and we came out of the ocean, but we brought with us basically the ocean. We're basically little walking bags of ocean. It's sort of incredible.

• 26:40Kelly Weinersmith?

  It is amazing. Yeah. And so these three different domains differ in things like what makes up their cellular wall, how they structure their genes. For example, bacteria and archaea tend to have circular chromosomes, and eukaryotes tend to have linear chromosomes.

• 26:56Daniel Whiteson?

  So eukaryotes are distinguished because they have a nucleus. How do you tell the difference between prokaryotes and archaea?

• 27:02Kelly Weinersmith?

  Yeah, so prokaryote is a phrase that just refers to organisms that don't have membrane-bound organelles, as I understand it. And I think that because we've created this distinction, people often think that archaea and bacteria are closely related because they're both prokaryotes. But as I understand it, archaea, bacteria, and eukaryota are all pretty like similarly distant. Like archaea aren't that much closer to bacteria than they would be to us.

• 27:30Daniel Whiteson?

  All right. I feel like you trying to understand the difference between leptons and hadrons and mesons and stuff. So we have eukaryotes, which are on the side, then we have prokaryotes. And within prokaryotes, we have bacteria and we have archaea. Is that right?

• 27:44Kelly Weinersmith?

  I think so. I did not prepare that ahead of time. I'm trying to pull this out of Kelly intro bio brain, but I never had to teach intro bio, so it never solidified.

• 27:52Daniel Whiteson?

  So then why are archaea thing? How are they different from bacteria?

• 27:55Kelly Weinersmith?

  So they're different in that they have like different kinds of cell walls. They have a different way of initiating protein synthesis. I think they differ in the way that they translate and transcribe their chromosomes. So they differ in the way that they sort of read and turn into proteins, the information that's in their genetic sequences. And those are the notes that I have written down.

• 28:19Daniel Whiteson?

  And so tell us about viruses. Why are they not in the tree? Are they not alive? How do you define life? All this stuff?

• 28:26Kelly Weinersmith?

  There's a number of different criteria, depending on who you talk to. Some of them will have different definitions than others. But two important features that tend to pop up in a lot of the definitions is that in order to be alive, you need to be able to do some of your own metabolism, some of your own metabolic processes. You need to be able to like convert stuff into energy that you can use. And you need to be able to replicate yourself. And so viruses, they don't have any metabolic machinery. They just inject themselves into a cell and then they hijack the cell's machinery to create more virus particles that then burst out of the cell and go off and start that process again.

• 29:02Daniel Whiteson?

  And is there some like philosophical justification for this? Or is this just an arbitrary dotted line that humans draw between a big continuum of biological activity?

• 29:11Kelly Weinersmith?

  I think it might be, what do I think?

• 29:14Daniel Whiteson?

  Is this like planets and dwarf planets all over again?

• 29:16Kelly Weinersmith?

  Yeah. So I was wondering that while I was working on this outline. And that's what kind of made me go to the tree of life. And I think part of why we can't really fit them on the tree of life is that they just sort of don't fit anywhere on there neatly. And I wonder if because we couldn't neatly fit them on there anywhere, we're like, all right, well, you don't do these other things that are important. And if you were doing those things, you'd have more genetic information and we could use that to help fit you into the tree of life because we could see like, you know, what the blueprints were and how that fit onto the tree. But you don't have that. And so I wonder if part of it is just like, well, we don't know where to put them on the tree of life. So we're just going to say they're not alive. And I bet a bunch of the people who come up-

• 29:55Daniel Whiteson?

  Problem solved.

• 29:55Kelly Weinersmith?

  Problem solved. But I'm sure a lot of people who come up with these definitions are going to be like, that is a stupid answer. These are, it's very important to be able to like, you know, make your own energy and reproduce. And they don't do it. So they, they are not as good as us in some way.

• 30:09Daniel Whiteson?

  All right. Well, if you have strong opinions about the definition of life and whether viruses are alive or not, write to us with a strongly worded email. We would love to hear from you.

• 30:16Kelly Weinersmith?

  Yeah, no, I would, I think it would be fun to have a battle about the different definitions of life. Not a battle, a conversation, a genial conversation.

• 30:24Daniel Whiteson?

  And I love when these mysteries have the context, you know, I think- It's really cool that when we look at planets, we also see other stuff that's almost a planet. It helps us understand like where it sits in the bigger question. And I love, you know, that there are other great apes that are still around. Like, I wish there were more species of humans that survived to today because it would tell us so much more about our evolution and our context. And so I think it's really cool that we have not just life and inert stuff. We have this like weird stuff on the boundary that helps us understand like what life means. So that's very cool.

• 30:54Kelly Weinersmith?

  And so you might be wondering, why did we talk about what archaea are? And then why are we talking about if viruses are alive or not? And the answer is that this, there was a finding recently of a new species of archaea. Does Katrina pronounce it archaea or am I?

• 31:08Daniel Whiteson?

  Archaea, yeah.

• 31:09Kelly Weinersmith?

  Yes, great, okay. Because if Katrina does it, then I'm doing it right. So, uh, so anyway, so there was a new species of archaea that was discovered. And it has a very small genome and doesn't seem to do a lot of metabolizing. And so there was this idea that went around the popular press that maybe this is like a transition between things that are alive and not alive. Because there's this critical feature of being alive that is missing from this species.

• 31:33Daniel Whiteson?

  Ooh, so more of the fuzzy context.

• 31:35Kelly Weinersmith?

  More fuzzy context. So let me tell you a little bit more about this discovery. So they were looking in dinoflagellates, which are these single-celled eukaryotes. You find a lot of them in the ocean. They tend to have like these two flagellum, which are like long stringy things that they sort of move around to help them get, get from one place to another. And one of the things that's interesting about them is that they produce bioluminescence, which you can see in the ocean and.

• 32:00Daniel Whiteson?

  Ooh, pretty.

• 32:01Kelly Weinersmith?

  Oh, my gosh. Once I jumped into the ocean when the bioluminescing organisms were in there. And there was this like amazing blue light that just kind of like, oh, it was one of the coolest experiences of my life. This was in Maine, in northern Maine.

• 32:13Daniel Whiteson?

  Wow.

• 32:14Kelly Weinersmith?

  Yeah, I was at a science conference. It's, it's pretty sweet being a scientist sometimes. So anyways, dinoflagellates, they do that, but, but the scientists were not interested in that. They were interested in the fact that the dinoflagellate that they were looking at was thought to have a symbiotic critter living inside of it. And so they were trying to understand that symbiosis and how this, it was a cyanobacteria, might be benefiting the dinoflagellate. And well, and so they essentially opened up the dinoflagellate. Sorry, dude. And they sequenced the stuff that was inside. And when they sequenced the stuff that was inside, they found an additional circular DNA sequence that they weren't expecting to see. And they did a bunch of extra studies to look at it and try to convince themselves that they hadn't messed something up because what was surprising about it was that it was

• 32:59Kelly Weinersmith?

  so stinking small. The circular DNA was so small that it was about 5% the length of a genome you'd find in something like ischeria coli or E. coli. So like very common bacteria. And again, they thought it was a mistake, but they kept sequencing it and then they assembled it. And when you assemble it, what you essentially do is you look at the genetic sequences and say, okay, do these sequences match up with anything we see anywhere else in the tree of life where we know what it does? So trying to get a handle on like, what might these sequences do based on what we know happens in other organisms? It was about 230 ish kilo base pairs where kilo means like a thousand, right, Daniel? Yeah, I always double check these things. So super tiny.

• 33:42Kelly Weinersmith?

  And so, once they convinced themselves that they weren't messing up something, they put it on the tree of life and they were like, okay, this appears to be archaea. It looks like it's a whole different phylum of archaea that we haven't seen before. And then they went through and they looked at what was in the genome. And they're like, okay, based on what we know about other organisms, what do these genome components do?

• 34:03Daniel Whiteson?

  So let me back up and ask you a question, just to make sure I understand. Because my understanding is when you sequence something, you don't just like pull the whole DNA out of the nucleus and read the whole thing. You do this process, we basically like shred the cell, chop up the DNA into a bunch of short bits. You sequence all the short bits like shotgun sequencing and then you use computer programs to like sew it back together. And this is like Craig Venter's big innovation decades ago that made the human genome much faster. And so then you have this mystery sometimes of like, well, where do these pieces all go together? And I think what you're saying is that when they were putting the puzzle together, they realized, oh, we're solving two different puzzles here. This is not one big puzzle. It's like if you started working on a jigsaw puzzle and you noticed like, oh, this is Lots of weird blue pieces that don't fit into the puzzle,

• 34:49Daniel Whiteson?

  but they do fit with themselves over here in the corner. Is that what happened?

• 34:52Kelly Weinersmith?

  Yeah, that's an incredible explanation, actually. And so they didn't just find two critters. They actually found more than two critters in there. And so they put multiple puzzles together. And a lot of the other puzzles, they were like, OK, we've seen these puzzles before. But then, then when they found Sukuna archaea,

• 35:10Kelly Weinersmith?

  they were like, what the heck is this? And at first, they didn't trust that it was anything.

• 35:13Daniel Whiteson?

  I see.

• 35:14Kelly Weinersmith?

  But once they convinced themselves that it was real and they hadn't like made some mistake through the part of the process, they discovered that it appears to be a whole new phylum of archaea. And then they went through and there are a bunch of public databases where people are like, they collect genetic information and then they put it online. And when they started searching through that, they found a lot of other sequences that were, looked kind of like this. And so they think that this is the first example in the phylum that's been described, but that there's probably a bunch of other stuff out there that we've sort of seen but not recognized yet.

• 35:45Daniel Whiteson?

  All right. And so what makes this one different from other archaea? What makes it have its own phylum and makes it, you know, whip through the popular press and get an article in Science?

• 35:53Kelly Weinersmith?

  So what was particularly exciting was that when they tried to figure out what the few genes that were there did, most of them were associated with replicating the organism. So it could do its own reproduction. But there were very few, if any, genes associated with metabolism. And so it looks like it's somewhere between alive and not alive. So I mentioned, you know, the definition of being alive. You've got to be able to do your own metabolism and your own reproduction. This doesn't seem to be doing its own metabolism. So it's probably a parasite of some sort, but it can do its own reproduction.

• 36:30Daniel Whiteson?

  So it can't do its own metabolism? Because even a parasite, like, you know, something inside of you that's drinking your blood, it's still metabolizing the blood and like feeding its own internal chemistry. So what does it mean to not be able to do your own metabolism? Does it mean that like you're just stealing directly the chemical products that store the energy?

• 36:48Kelly Weinersmith?

  I think so. I don't actually understand how you could not metabolize. I mean, I guess in the same way viruses don't metabolize things. They just hijack machinery. I suspect that's what's happening here.

• 36:58Daniel Whiteson?

  I see. Yeah. Fascinating.

• 37:00Kelly Weinersmith?

  Yeah. And so most of the paper is like scientific details, but at the very end, the authors say something to the effect of like, maybe this is like an intermediate step.

• 37:10Daniel Whiteson?

  Oh.

• 37:10Kelly Weinersmith?

  And like, this could tell us something about how organisms go down the path to becoming a virus. Maybe you lose a bunch of stuff as you go.

• 37:21Daniel Whiteson?

  Oh.

• 37:21Kelly Weinersmith?

  And you end up with these very like shortened genomes. And not everybody was convinced.

• 37:25Daniel Whiteson?

  It's like a company that's deciding, hey, we don't need to have our own HR department. Let's just outsource it to some startup or AI or something.

• 37:34Kelly Weinersmith?

  And then they become parasites.

• 37:38Daniel Whiteson?

  Wow. That was a quick step to criticizing corporate culture, wasn't it?

• 37:42Kelly Weinersmith?

  Yes, that's right.

• 37:43Daniel Whiteson?

  But that's fascinating to suggest that viruses used to be more fully alive and have sort of lost this capacity or optimized themselves. So they realized they didn't need it. That's fascinating.

• 37:54Kelly Weinersmith?

  Yeah, it's an interesting idea. I don't know if it's an idea that's been presented elsewhere. And this was just an example that really illustrated that that idea might have some legs. But, you know, not everyone was convinced. So I read this paper in Science that was summarizing. So I should also mention that the paper we're talking about, the results are on Bio Archive. So they haven't gone through peer review yet, but they're publicly available. But people got immediately excited when it went on Bio Archive and Science covered it.

• 38:19Daniel Whiteson?

  Yeah.

• 38:20Kelly Weinersmith?

  And Science did some interviews with other people and they found a San Diego State University biologist, whose name is Elizabeth Waters. She wasn't part of this study, but she does look at small archeal parasites. And she said that maybe this is a virus in the making. She said, this is a bit of a jump. If true, amazing. So she's like a little skeptical. If it turns out, that would be super cool. But there are other organisms with very small genomes. I think this one is particularly small, but it's not necessarily the case that, you know, a small genome organism is, you know, the missing link between becoming a virus.

• 38:59Daniel Whiteson?

  And this is an example, folks, of good journalism here because they went out and talked to somebody who wasn't invested in hyping. This result and who knows the details and asked her like, are you impressed by this? And she was like, hmm, hmm, you know, she's holding her fire a little bit. And that tells you like, we're not all convinced that this is a big change. That, you know, everybody's now going to update the textbooks or something, but it is exciting and promising.

• 39:23Kelly Weinersmith?

  Yeah, absolutely. And to me, this highlights, um, you know, so maybe this is a little bit of a self defensive statement I'm about to make here. So, you know, you, you've said that when physics is doing well, it's doing more than just taxonomy. This is essentially just taxonomy. They found something new. They were like, well, let's look at this new thing. And maybe this is leading to a brand new understanding of life or not life, depending on what you call viruses. Uh, you know, and just how things work and understanding our world a little bit better. And so I would argue just taxonomy is really important. Thank you for this fascinating just taxonomy. And thank you to Piptar Cat for this fantastic Discord question.

• 40:05Daniel Whiteson?

  Well, if I could comment, I think that this is a fantastic bit of science, but I think it's especially interesting because it's not just taxonomy, right? You're not just putting it there and saying, well, look, it's just there. You're thinking about the consequences, you're drawing analogies, you're asking philosophical questions about what it all means. So taxonomy is very valuable, partially because it inspires this kind of deeper thinking and making these connections. So I would say taxonomy is step one in a really fascinating and valuable process.

• 40:34Kelly Weinersmith?

  Right, but you can't get to step two without step one, but I'll, I'll give you.

• 40:37Daniel Whiteson?

  Yes, agreed.

• 40:39Kelly Weinersmith?

  Okay, I'll, I'll give you that.

• 40:49Speaker 05

  Cash flow crunch? OnDeck's small business line of credit gives your business immediate access to funds up to $200,000 right when you need it. Cover seasonal dips, manage payroll, restock inventory, or tackle unexpected expenses without missing a beat. With flexible draws, transparent pricing, and control over repayment, get funded quickly and confidently. Apply today at ondeck.com. Funds could be available as soon as tomorrow. Depending on certain loan attributes, your business loan may be issued by OnDeck or Celtic Bank. OnDeck does not lend in North Dakota. All loans and amounts subject to lender approval.

• 41:20Speaker 02

  Hey, it's Niall Rogers, host of Before the Moment, a Lincoln original series. I'm driving across the country, meeting some of today's most fascinating artists. We're exploring the stories before the moment that changed everything. This week, I'm joined by rising star Sienna Spiro.

• 41:40Speaker 07

  My first ever in the world show was when I was 10, and I sang at a pub called The Georgian Devonshire. I was so nervous. I was 10, so they let me in only to sing my song and they kicked me out right after. And then I remember I wrote, I've been writing since I was 10, so I wrote this song called Lady in the Mirror. Made this little track with it, but I just like pressed it. And I remember I sang this song and there was like five people in there. And I remember how myself I felt, and I felt like I understood myself and understood what I needed to do.

• 42:06Speaker 02

  So does that take us back to, I sing just to know I'm alive?

• 42:10Speaker 07

  Hundred percent, hundred percent, my whole life.

• 42:13Speaker 02

  Experience Before the Moment, a Lincoln original series on the iHeart Radio app, YouTube, or wherever you get your podcasts.

• 42:33Daniel Whiteson?

  Okay, we're back and we're answering questions from listeners. If you have a question about the universe you've never really had satisfactorily answered, please write to us. We would love to give it a shot. You can email us to [email protected]. You can join our Discord and you can find the link to that on our website, danielandkelly.org. We really would love to hear from you. So many people write in and we respond, and then they say, oh my gosh, I can't believe you actually wrote back. Well, we really do. You will hear from us. Your message will not just be ignored in the black hole of the internet.

• 43:03Kelly Weinersmith?

  That's right. We can't wait to hear from you.

• 43:05Daniel Whiteson?

  All right. And so now we have a really fascinating physics question from John. Hi, Daniel and Kelly. My name is John Chai. My question is, what would happen if the speed of light suddenly changed? Like, let's say a giant cosmic switch were flipped and suddenly the speed of light got cut in half. Would it be completely catastrophic for all of existence? Or would it go largely unnoticed? Because even half of the speed of light is still really, really fast. Thanks a lot and thanks for the great show.

• 43:31Kelly Weinersmith?

  Oh, this is fantastic. And I think this is another one of those, you know, questions where, so you're always encouraging us to take what we know. And think, you know, if we tinkered with it a little bit, how would that, you know, break the universe? And, and essentially like, understanding how tinkering with things would change things helps us understand if we really understand what's happening.

• 43:49Daniel Whiteson?

  Yeah.

• 43:50Kelly Weinersmith?

  And I use the word understand a lot because I'm the most articulate person on the planet. But you understand where I'm going, so.

• 43:57Daniel Whiteson?

  Yeah, and this actually connects to our earlier conversation about the Fermi paradox. You know, another way to imagine what aliens might be like, that would make them very alien is if they lived in a relativistic environment. You know, what if they evolved in a situation where they're very often going at eight tenths of the speed of light relative to each other? Or relative to their houses or something? And so they observe relativity in action as children and they develop an intuition for it. And to them, it makes perfect sense that moving clocks run slow and moving yardsticks look short and all this kind of stuff. You know, to them, the universe would be very different and their path of their science would be very different than ours. But here, John is asking a different question.

• 44:39Daniel Whiteson?

  Basically, he's imagining that he's at the control panel of the universe. And he's got in front of him all these fundamental constants. Because there are these weird numbers in the universe that seem to control how physics works, you know? Why is the weak force weak? Why is the strong force strong? Why is gravity so weak? Why is the universe this big and not that big? Why are galaxies this size and not bigger? How come stars get this size? Like, there are all these numbers in physics and some of them seem arbitrary. And so he's wondering, if he was at the control panel and he cut the speed of light from three times 10 to eight meters per second, down to half of that, what would change? How would the universe look different? Would we notice?

• 45:19Daniel Whiteson?

  And I think part of the motivation for this question is that the speed of light is so fast that it's essentially infinite. You don't take into account when you're walking down the hallway, the fact that the light that's hitting your eyeballs. Is a little bit out of date and the person walking the other direction is not actually where they appear to be. They're slightly ahead of it because the light has taken some time to reach your eye. We treat it as instantaneous. So I think he's wondering what life would be like, what the universe would be like if it wasn't so instantaneous, if we sensed that delay, if the speed of light was slower and like maybe closer to the speed of sound.

• 45:51Kelly Weinersmith?

  Can I guess? So I, I feel like because it's going so fast, day to day, we wouldn't notice anything. But when we were looking out at like stars, we'd have to take into account the fact that what we're seeing was even farther back in the past. But how am I wrong?

• 46:06Daniel Whiteson?

  No, I think you're mostly right. But before we dig into all those consequences, I have to nerd out for a little bit about what it means to change the speed of light. I mean, I think if you're standing at the control panel of the universe, the speed of light is not one of those numbers, one of the knobs for determining the nature of physics. I think those knobs need to be dimensionless numbers, not things with like meters per second in them. And not just because meters and seconds are things humans invented, but because the dimensions make it connected to so many other constants. Like, for example, you could change the speed of light without noticing anything if you also at the same time accommodated other things, like you change the length of a meter and you change the speed of light. We wouldn't

• 46:47Daniel Whiteson?

  even notice. It'd be like, if you scale up the whole universe and you scale up all the rulers, there's no change. You can't tell if somebody does that. And so, for example, if you change the speed of light, do those other constants also change? Like, the speed of light can be expressed in terms of quantities from electromagnetism, which include things like the vacuum permittivity of space. So if you change the speed of light, you also change those which change, you know, how electricity works? Or are you somehow breaking the universe and changing the laws of physics themselves? If you change dimensionless constants, you can keep all the laws of physics the same. And every time you change those, you really do get an effect. If you change dimension full constants, then it's more complicated and ambiguous exactly how it

• 47:30Daniel Whiteson?

  propagates through. But, you know, we can make some simplifying assumptions and play with it anyway.

• 47:34Kelly Weinersmith?

  And see, the speed of light is a dimension full constant, right?

• 47:38Daniel Whiteson?

  Yeah, because it's Meters per second, right?

• 47:41Kelly Weinersmith?

  Okay, got it.

• 47:42Daniel Whiteson?

  Has two dimensions to it. And you're right, the speed of light is super duper fast. Like, the fastest any human has ever traveled relative to like a nearby object, you know, on Earth, is something like point zero zero three seven, the speed of light.

• 47:55Kelly Weinersmith?

  Wow.

• 47:56Daniel Whiteson?

  And, you know, that's like astronauts in the space shuttle orbiting the Earth, right? And so we're talking about tiny, tiny fractions, which is why we don't observe relativistic effects. But you're right, one of the ways that we do notice the speed of light is in terms of what fraction of the universe we can see. We look out into space and we see back to the beginning of time. And we can do that because light takes time to get to us, because the speed of light is not infinite. And so the furthest thing we can see is something where the photons were emitted at the very beginning of the universe, essentially like 380,000 years after the Big Bang, and have been flying to us ever since. And the speed of light limits how far we can see.

• 48:38Daniel Whiteson?

  So if the speed of light was half what it was, we would be able to see less of the universe, because those photons we're seeing now wouldn't have had time to get here if the speed of light was half of it. So the universe would still be the size that it is, but we wouldn't see as much of it.

• 48:54Kelly Weinersmith?

  And how would that impact our understanding of the universe, do you think?

• 48:57Daniel Whiteson?

  Oh, yeah, that's a really fascinating question. You know, I think we would still see a lot of the structures. Obviously, we could still see the whole solar system and the galaxy and the structures of the galaxy, like the galactic clusters and the nearby galactic clusters. Those are not so far away. And we would still see the early universe. It's just that photons from the early universe are becoming from a closer bit of the early universe than in a scenario where the speed of light was faster. So to directly answer your question, I don't think that would make a big difference, right? We would still see the whole history of the universe. It's just in a smaller chunk of it. But the chunk we're seeing right now is really, really big. It's big enough that already we can see that when you zoom out, mostly the universe is uniform, right?

• 49:40Daniel Whiteson?

  That there's not a lot of structure at the highest level. I mean, there's solar systems and galaxies and galactic clusters. But once you zoom out past that, it's basically just foam. You know, there's no real structure anywhere. And so we can see enough to get that, which I think is the biggest structure in the universe. And so it's big enough and the universe is old enough for us to glimpse that. But there is a connection there.

• 50:03Kelly Weinersmith?

  You're just a little... Bubble in the foam of the universe that nobody would notice if it popped.

• 50:10Daniel Whiteson?

  But you know, the structure of the universe also would be different if the speed of light was smaller, because the speed of light is not just the speed of light, it's the speed of information. And it limits the biggest structure you can make at any point in the universe. Like, in order for a structure to form, you have to have it interact and communicate. Like, even gravity is limited by the speed of light. And so, there isn't time, for example, to form a structure that's bigger than the speed of light times the age of the universe. It just hasn't had time to, like, gravitationally assemble. And so, if the speed of light is slower, that means the biggest structure you can have would be smaller in the universe.

• 50:49Kelly Weinersmith?

  Oh, and so what is the biggest structure that we have? What would be ensmallened by this, this slower speed of light?

• 50:58Daniel Whiteson?

  Well, this is actually kind of a current mystery, because we see structures like the Sloan Great Wall. This is like sheets of galactic clusters, which at the highest level, like the edges of those bubbles in the foam. Though, some of those are bigger than the speed of light times the age of the universe. So it's a bit of a puzzle, like, how did that form? Are we misinterpreting it? Something that we didn't understand. And one of my favorite things about science is that we have all these threads that should all tell one story, because we think there's a thing that's happening in the universe. And when they don't, that's a hint that there's something we don't understand. And there's so many different ways to attack the same question. So that's a current mystery. But yes, some of those biggest structures, you know, superclusters of galaxies woven together into foams and voids, would be smaller.

• 51:43Daniel Whiteson?

  So basically, like, the foam would have smaller bubbles.

• 51:46Kelly Weinersmith?

  Okay. All right. So we've looked at the very big picture. If we go back to Earth, what would be different? So like, when I turn on the light switch, I probably wouldn't, there wouldn't be, I'm guessing there wouldn't be like a noticeable difference in how long it took for the room to get bright. What about other stuff?

• 52:04Daniel Whiteson?

  Yeah, so the speed of light is so fast that even half the speed of light is crazy fast, and there's no way that you would even notice. But we might have been able to measure the speed of light a little bit sooner in our history, right? People tried to measure the speed of light for decades with all sorts of hilarious contraptions, with lanterns across mountains. And basically, there was like, yeah, it's just too fast. We don't know. It's faster than we can measure. So we would have figured that out sooner, which might have given us a handle on relativity earlier. And so I think in that universe, we might have figured out physics 100 or 200 years earlier, which is pretty cool.

• 52:38Kelly Weinersmith?

  Then we wouldn't have had Einstein. Because what would he have done? Probably nothing.

• 52:43Daniel Whiteson?

  Somebody else would have been Einstein.

• 52:45Kelly Weinersmith?

  Okay, all right, all right. But would he have had the same hair? That's the important question.

• 52:50Daniel Whiteson?

  Really, that's what it all comes down to. This whole production is really just to get us to Einstein's hair.

• 52:56Kelly Weinersmith?

  That's right. That's right.

• 52:57Daniel Whiteson?

  But if you imagine like slowing down the speed of light even more, so that its effects are visible every day, like imagine if cars moving along highways were relativistic, you know, if they were moving at like eight tenths of the speed of light, you know, because the speed of light was crazy slower, then we would have that kind of alien intuition. We would notice relativistic effects every day, right? Like, we would see that cars moving along the highway are shrunken, and that, you know, the people on airplane trips don't age as much, right? And it would really change the experience of going like on a long flight. You take that 14 hour flight to Dubai, doesn't feel like 14 hours, right? Only feels like 10 minutes or something. So that's pretty cool.

• 53:42Kelly Weinersmith?

  Yes.

• 53:42Daniel Whiteson?

  You don't get to watch seven movies, but you also get your time back, right?

• 53:46Kelly Weinersmith?

  Yeah.

• 53:47Daniel Whiteson?

  So that would be really cool. But it would also make things really hard. Like, it's already challenging for me to figure out my calendar with time zones, you know, like, which time zone are they in? What does that mean for me? Like, I don't know why that's so complicated. Now imagine that on top of that, you need to take into account relativistic effects. So like, where has Daniel been? Where is his clock? How slower is it? It would make coordinating things much more complicated because we'd have to give up on the Of simultaneity, one of the weirdest consequences of relativity is the fact that clocks are not synchronized, which means you don't all agree on the order of events. And mostly on the surface of the earth, we can't notice that because everybody's moving very slowly. But if we were moving faster relative to the speed of light, that would be a real effect.

• 54:32Daniel Whiteson?

  And people would disagree about important stuff. And yeah, that could have real consequences. It would make life a lot more complicated.

• 54:38Kelly Weinersmith?

  And just to remind myself, you're talking about if it was more than just half the speed of light, it would have to be, yeah, quite a bit more. Okay.

• 54:47Daniel Whiteson?

  Yeah, just half the speed of light probably would have almost no measurable effect on life on earth. Except maybe it would take longer to like, download a movie from some website in Siberia. Because the speed of light also influences your download times, right? Like you're downloading data from across the earth. That's a significant difference. And so the ping time between your computer and that computer is limited by the speed of light, because that's the speed signals move across the internet. And so it would take a little bit longer. You know, in that case, when you're downloading a big movie, the latency is not a big effect. But if you're trying to have like a conversation in real time with somebody on the other side of the earth, then there could be more lags there.

• 55:27Kelly Weinersmith?

  Well, I'm glad that the speed of light is what it is then. Because otherwise, it would be hard to record this podcast with you.

• 55:32Daniel Whiteson?

  That's true. And then looking out into the cosmos, there would be other changes, actually, in what we see out there. Black holes would be much more significant. The size of the radius of a black hole depends on the speed of light. If you calculate the Schwarzschild radius, the point past which things can't escape the gravity of a black hole, that has a factor in it from the speed of light. It goes like one over the speed of light squared. So if you shrink the speed of light, that means a larger event horizon for the same mass, right? So black holes with mass in our universe would have a much larger radius in this universe, where the speed of light is smaller. This means they could have like a bigger effect on their galaxies, right?

• 56:16Daniel Whiteson?

  We have black holes at the center of all galaxies, and they're really massive, but they're not that big. You know, they're tiny compared to the size of a galaxy. Galaxy, but crank down the speed of light by a big factor and they can grow. And so like the centers of galaxies could have like gargantuan black holes, not more massive than the current ones, but just bigger. And that could actually help them grow to more massive quantity. So it would really change black hole physics a lot if you change the speed of light.

• 56:42Kelly Weinersmith?

  But, but we probably would not get sucked up by a black hole. I guess everything could be different if all the black holes were different sizes.

• 56:49Daniel Whiteson?

  In the end, you gotta make it about yourself, Kelly, right? What is the impact on Kelly's life?

• 56:53Kelly Weinersmith?

  Have you met people? I'm just asking the question that the people are asking themselves.

• 57:00Daniel Whiteson?

  Y'all are gonna be fine. Don't worry.

• 57:01Kelly Weinersmith?

  Thank you, Daniel.

• 57:05Daniel Whiteson?

  All right. Well, thank you very much for that question, John. Let us know if we scratched your Doppler itch.

• 57:10Speaker 05

  Hi, Daniel and Kelly. Thanks a lot for pondering my question and I really enjoyed listening to your speculation on how our world might be different if the speed of light got cut in half. And I also enjoyed listening to you think about what might happen if we took it to the extreme and it slowed down to like a noticeably slow amount. To be honest, I was hoping for some explanation of how changing the speed of light might be catastrophic to our existence, but I guess in science, it really doesn't depend on what you're hoping for. Thanks a lot and thanks for the show.

• 57:42Daniel Whiteson?

  All right. Thanks very much to everybody who sent in their question. And please, please, please don't be shy. We really do love hearing from you. Write to us, [email protected], tweet at us, interact with us on Blue Sky or join us on the Discord. Check out all those directions at danielandkelly.org.

• 57:57Kelly Weinersmith?

  See you then.

• 58:05Kelly Weinersmith?

  Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio. We would love to hear from you.

• 58:10Daniel Whiteson?

  We really would. We want to know what questions you have about this extraordinary universe.

• 58:16Kelly Weinersmith?

  We want to know your thoughts on recent shows, suggestions for future shows. If you contact us, we will get back to you.

• 58:23Daniel Whiteson?

  We really mean it. We answer every message. Email us at [email protected].

• 58:29Kelly Weinersmith?

  Or you can find us on social media. We have accounts on X, Instagram, Blue Sky, and on all of those platforms, you can find us at D and K Universe.

• 58:39Daniel Whiteson?

  Don't be shy. Write to us.

• 58:43Daniel Whiteson?

  With ChatGPT, you can do more.

• 58:45Speaker 05

  Than get answers. You can get things done. Whether you're leading a big project, planning an elaborate trip, or trying to balance work and life, ChatGPT can help. Give it a goal, plus things like files, notes, or project plans, develop a trip itinerary with daily updates, or create a prioritized schedule. So you can spend less energy sorting out the details and more on bringing your biggest ideas to life. Get started at chatgpt.com.

• 59:10Speaker 01

  This is Shirley Strawberry from the Steve Harvey Morning Show. Buy smart, drive for less, and trade for more. That's Toyota affordability. And it starts with a great deal on an all-wheel-drive Camry, Corolla Cross, or a Corolla Sedan, with the latest features and tech. Or test drive a spacious Grand Highlander or Adventure Ready RAV4. And with so many hybrid models available, you can enjoy longer trips without all the stops. While Toyota's legendary resale value means you could get more at trade-in, get a great deal today and a great value tomorrow. Shop toyota.com for deals and details. Toyota, let's go places.

• 59:52Speaker 02

  Hey, I'm Niall Rogers. This fall, I'll be driving across the country, meeting some of today's coolest and most fascinating artists. We'll explore the stories before the moments that changed everything. Because every musician remembers the moment where it all began. Experience Before the Moment, a Lincoln original series on the iHeartRadio app, YouTube, or wherever you get your podcasts.

• 1:00:23Speaker 01

  This is an iHeart Podcast. Guaranteed human.