Listener Questions #40

24:46They're just like eating our garbage, you know. But yeah, nobody wants to see them. You're getting paid by the cockroach lobby or something. I don't, I'm not buying it. The cockroach is funding me. Exactly. Yeah. All right. So the jewel wasp, if it's lucky enough, gets a sting into like the chest area of the cockroach. Yeah. And in the sting, it injects a venom. And that venom paralyzes the cockroach's front legs for like five minutes so it can't move. and then it stings it again in the head. And we go into a lot of detail in that prior episode about where it's going in the head, what it's doing.

25:17But essentially the cockroach is then like - What kind of sound does it make when you inject the venom into the head? Is it like a - Or what? It's probably pretty quiet. I don't know that we've been able to record it. That's a good question. No, I want to hear your best guess. I don't know. I tried to make the noise you made. I don't know what you were thinking. I don't know either. It was just so visceral. I had this image in my mind when you were describing it. I was just wondering what it sounded like. All right. So this is terrible already. I'm feeling really bad for the cockroach. What happens next?

25:48So the cockroach starts like excessively grooming itself and stays in one spot for a long time. The jewel wasp goes off and figures out where it wants to hide the cockroach so the cockroach doesn't get eaten by anything. And so then when it finds that spot, it grabs the cockroach's antenna and walks it sort of like a dog over to this little area. Amazing. And then it lays an egg on the cockroach and then it closes up the little hole. And when the egg hatches, the baby will consume the cockroach, which has pretty much not been moving and is just kind of hanging out in there. And it is a parasitoid because the babies are going to consume and kill the cockroach.

26:21And so it rides this thing like ratatouille, right? It's like standing on it, like driving it. No, no, it's not riding it. That would be really awesome. No, it's like holding on to the antenna and pulling the cockroach to where it wants it to go. I see. Yeah, so the antennae— Kicking and screaming. Wow. Yeah, it looks like it's going willingly. Like, that venom does some amazing things when it's injected into the brain of the cockroach. And what's the virus aspect of this? The venom contains a virus? It's, like, not enough for the venom to be, like, debilitating and humiliating and painful. It's also got to have, like, a DNA payload?

26:56Great question. So we don't understand wasp venom very well. So wasps have venom glands, and when they inject venom into their hosts, it can contain a lot of stuff. And one of the things that it contains is virus particles or, like, viruses. And so we're starting to understand what these viruses do. In a lot of cases, we know that they're there, but we have no idea what they do. One of the things that they do, and now we're moving away from the dual wasp example. That was just my definition of a parasitoid, my way of introducing the idea of venom. But now we're talking about viruses. Because they're in the venom.

27:31In some cases, they are in the venom. It's not the case that every parasitoid wasp has a virus in its venom, but in some cases, it looks like parasitoid wasps are also injecting venom and that that venom often helps the parasitoid wasp. So let's go for an example where the venom seems to be helping the parasitoid wasp. There is another kind of parasitoid wasp that lays its eggs inside of ladybugs or lady beetles, depending on what you want to call them. Oh, man. Now we're torturing ladybugs, Kelly. Yeah, we've got a lot of not-native ladybugs in this area. So they've got a sort of low sympathy.

28:08Like, they aggregate in my home at certain times of year, and I'm like over them. Sorry. What kind of person do you have to be to be angry at ladybugs? What? Are you saying? You try having them in your house and finding them on your toothbrush and being like, no, this is mine. Go away. I don't know. I don't have any trouble getting mad at ants or whatever, but like ladybugs. You know they're little predators, right? Okay, anyway. Let's go on and do horrible things to ladybugs. Man, biology is ruthless. Yeah, well, it is. So, all right. So the wasp lays an egg inside of the ladybug. And that egg contains a virus that was like replicating in the oviduct of the wasp.

28:51So the baby wasp hatches and starts going through development. and the virus starts replicating. Oh. And the immune system of the ladybug starts to be suppressed and the virus starts moving into its nervous system, like the ganglion in its head and stuff. Oh, man. And around this point, the wasp baby is ready to emerge from the ladybug and then it forms like a cocoon underneath the ladybug's legs. This is like Alien, right? Where you lay an object and it crawls out from inside you. Exactly. And dances on the countertop and all that kind of stuff. Except in this case, the lady bug isn't totally dead yet.

29:27And so I know. So she's got she's got this virus in her brain. And now she's got this like cocoon underneath where the baby wasp is still finishing some of its development. And whenever something comes by, she starts like having tremors and moving around like crazy, which is helpful for the baby that's developing underneath her. We call this bodyguard behavior because there are predators that want to eat, you know, what's inside of that cocoon. In some systems, there are hyperparasitoids, so like a parasitoid that wants to lay its egg inside of the baby of the first parasitoid. How dare you? I know.

30:03Well, I mean, nature's meat all the way down, I think. And so so that you've got this virus that's like in the nervous system, making the ladybug do these like tremors. but the ladybug's immune system at some point starts to be able to fight back against the virus. And as it fights back against the virus, the ladybug first starts doing a lot of these tremors because part of the immune response harms the brain, it looks like. But then eventually the ladybug is able to clear the virus and in some cases is actually able to walk away and live. What? I know. And this usually happens after the baby wasp has emerged and gone off as an adult to like, make more of this horrible thing happen.

30:44I had given up on any sort of happy ending possibility here. I was like deep into nightmare territory. And now you're saying that the ladybug can move on from this? Does it need therapy? I mean, is it okay? I mean, if ladybugs have therapists, I'm sure she's visiting one. But I don't know if that is an option. But yeah, it's crazy. And so these viruses have a couple different ways of working with the wasp host. So in some cases, they're like replicating in the wasp. And when the mom injects the egg with venom, some of those virus particles get in there, too. And then there are also some, and this is what Petri was specifically talking about when he sent the email in the video.

31:25There are some that actually have the virus DNA incorporated into its own genome. Wow. And so it will start making capsules for the virus to live in, and it will start making the virus on its own. And then it will put those two things together and inject that into the host. It like brews its own internal virus kombucha and then forces the ladybug to drink it. It does. So in this system, the virus is not actually integrated into the genome. This is an example where it looks like there's some viruses. We're not exactly sure what's going on, but we don't think it's specifically in the genome of the wasp.

31:58So there's a couple of different ways this can play out, but that's one of them. Yeah. So it's not part of the wasp. It's just like brewing this inside itself and then using it in the venom. Yes. Wow. Right. But when it's inside the genome, we call that a domesticated virus. It's been like taken up by the wasp and now the wasp gets to use it as it wants. But those that DNA sequence keeps getting passed on across generations. So it's sort of like if a physicist's wife is making kombucha on her countertop, it's not part of her genome. But if she eventually domesticates it to be internal so she could internally produce kombucha, that would be an example of a domesticated kombucha.

32:32And she might use it to manipulate you into, I don't know, doing the dishes more often, maybe twice your share. Or she wants to trick me into falling into a pizza. Maybe that's the whole plan. That she can eat you and get your energy. I'm going to make this all about myself. But that sounds fascinating. But I have a sort of obvious follow-up question I'm amazed that I don't see an answer to in the outline here, Kelly. I wait with bated breath to hear how I let you down. You're describing these incredible predators that inject venom into other creatures. and we recently had Matt Georgiani on the podcast to talk about snakes versus octopi.

33:11So the obvious question is like, if you had snakes versus wasps, like venom versus venom, life size, what's going to happen? Or do we need to reach out to Matt to ask him that hypothetical question? Well, so I asked Matt a little bit about wasp venoms and he suggested to me he wanted to stick with snake venoms, which I guess they're very different kinds of venoms. So my guess is if, you know, if a rattlesnake were to bite a wasp, Just the sheer mechanical process of injecting the venom would just crush the tiny little wasp. It wouldn't have a chance. If a wasp stung a snake, I don't know, it might hurt.

33:49Like when we get stung by wasps, we're not the intended target usually of the venom, but it still hurts. And so maybe a snake would also be like, dude, not cool. Go eat some ladybugs, man. That's right. I mean, I don't think it would get paralyzed. It would not, I imagine, get paralyzed like a lady beetle does, but it might be like, ow. All right. Well, thank you for answering my question. You're welcome. I was getting a little worried there. I thought maybe you were going to ask me for a scientific name just to mess with me or something. But of course, no. No, I was like, two spaceships are separated by a snake.

34:18And then that snake approaches the speed of light and gets bitten by radioactive wasps. And then the multiverse breaks and there's three or four of them. And yeah, depending on which universe you're in determines who wins. But OK. All right. Before we get too far off track, let's send this response to Petri and see if it answers his question. But I'm not done. So sometimes the wasps, I'm going to keep going. Please, I'm sorry. Yeah. Daniel, am I really only going to talk for 10 minutes about parasitoids and viruses? Give me a break, man. So sometimes these viruses, you know, you'll find that a wasp has transmitted a virus to its host.

34:55But that doesn't necessarily mean that that's something that's good for the wasp. So we have found some other instances where it looks like the virus suppresses the host immune response. That would also be good for the wasp. But we've also found situations where it looks like the virus is making the wasp do something that's bad for itself, but good for the virus. Oh, like who really is in charge here? Right, right. And so there's one system where the wasp usually tries to avoid laying eggs in a host that already has eggs in it because there would be competition between the offspring and now you're like sharing the food source.

35:30But when the wasp is infected by this virus, it's much more likely to do what's called super parasitism, which is, yeah, I know. The Marvel Universe version. That's right. And that's where you get a wasp mom laying eggs in a host that already has eggs in it. And we think that that's good for the virus because the virus can now jump from the eggs that it was deposited in to the eggs of the wasp that had been laid there before. And so that's how the virus manages to expand throughout the wasp population. And super parasitism doesn't seem to hurt the wasps a bunch in this case, but it definitely seems to benefit the virus.

36:07And so you got to be careful when you study this stuff. It's often fun to be like, oh, man, it's a collaboration between the virus and the wasp and they're ganging up on the host. But these things are complicated. And you need to think about, like, you know, the end goal for every single one of the players and try to disentangle what's happening. And, yeah, Game of Thrones-y or something. I wonder if it's sort of anthropocentric to ask, like, who's really in charge here? Because in the end, the whole system is just sort of co-evolving, right? And whatever works is whatever ends up happening. Well, yeah, and you could imagine that, like, it could start off as antagonism between the virus and the wasp.

36:44But after a couple of generations, something might change. And now their interests are a little bit more aligned. And so, yeah, I think this kind of stuff could change over time depending on how many hosts are available in the environment. This stuff gets complicated. And humans like things in nice little categories and nature doesn't care. Right. Exactly. And we like to attribute, like, intent to these things. Like, the virus has this plan to trick the wasp into laying eggs where it's not good for it. But, like, the virus has no plan. It's just doing that. And the viruses that succeed for whatever reason are the viruses we have.

37:17Yes, that's an excellent point. It's much easier and, frankly, more fun to describe these things in a sort of anthropomorphic way. But you're right. The virus isn't thinking, OK, now I have to do this, that, or, you know, now I have to make the wasp super parasitize the caterpillar. And, you know, it's not planning that detail. There's no corporate board meeting where they're like, what if we super parasitize? How would that work? And they pitched it with PowerPoints or something. Exactly. Thank God, because, man, then the viruses really would take over. Right. Yeah. And so I would say that this is a field that we are starting to understand, but there's a bunch of viruses that we see in venom.

37:52We don't know what they do. So we need to figure out what they're doing and how often they seem to be benefiting the wasp versus not. Open question, but super interesting. And now we can see what Petri had to say, because now I've had my fill of the nightmare fuel. Let's see if that means Petri will never sleep again at night. He's the one who asked the question. Buyer beware. That's right. Thank you very much, Kelly and Daniel, for the insightful response on your podcast. I very much enjoyed it. I never cease to be amazed and awed by the incredible ways life has evolved to manifest its diversity on our planet.

38:34I don't find it nightmarish at all. It's fascinating, but I also tend to sleep very well. Also, as someone who has spent a lot of time enjoying the fruits of home fermentation and happily shared these potables with others, I must say that I'm on the pro-kombucha side of the debate. Even homemade bread ferments away happily on the counter while it rises before being baked.

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41:50All right. And now Eric has a great question about how we take photos of particles. Hi, Daniel and Kelly. I'm wondering about how particle accelerators actually detect things. I've seen lots of podcasts and shows in the past that talk about the acceleration and how that works and how you get the particles up to speed and smash them into each other. But then they just kind of wave their hands about detecting things. And they don't get into detail about what's actually being detected, what's actually being measured, and how do you figure out what was in the collision? In high school, I remember looking at cloud chambers and doing the track analysis, looking at the radius and figuring out the mass and trying to work backwards.

42:32And I'm sure that's the precursor and it's related to that, but I'd love to know what are the actual detectors, what's being detected, what are those machines? Are they just really complicated digital cameras or are there other techniques being used to detect and figure out what actually occurred in that collision? Thanks a lot. All right. Love this question. And you're right, Eric. We often talk about the fun bit where you accelerate the particles and smash them together. But it's also really important to understand how we make measurements of the things that come out of it, because in the end, this is quantum mechanical and all we have are measurements.

43:06And then we're trying to infer the story of what happened. So it's crucial to understand, like, how do these detectors work? What are they really measuring? What do we know? And what are we inferring? And you're right that you can think of these things essentially as big, complex digital cameras, because digital cameras and particle detectors are actually the same thing. Digital cameras are particle detectors. Like the way your camera works in your phone is it has a CMOS chip in it, which is like a layer of silicon. And when a photon hits it, it displaces a bunch of electrons, and then those get read out on the side.

43:38And that's a particle detector. A photon is a particle. And the fact that your CMOS chip can also see other kinds of particles like muons is the whole basis for my side project to build a cosmic ray detector out of people's old cell phones. What is CMOS? I can't. That's a word I've never seen before. What is that? How do you spell that? You've never heard of CMOS? It's this green fuzzy stuff that grows on rocks, Kelly. Oh, come on, man. I've heard of that. S-E-A-M-O-S-S. And if the thing you're about to tell me about is not spelled exactly like that, then I win. You win. How do you spell? No, you win.

44:12It's CMOS, which stands for Complementary Metal Oxide Semiconductor. It's just a way to sandwich various semiconductors so that you get this property that when a particle crosses through it, it trips a bunch of electrons that you can then read out as a current. It's a way to create a digital signal from the passage of a particle. Okay, awesome. And it's also fuzzy and green. No, I'm joking. And so what we have at the Large Trade Zone Collider is like a generalization of that. It's like a big, fancy digital camera, but there's an important difference. It's not like we have a single camera that's just taking a picture of the collisions.

44:46We surround the whole collisions with sensors. So imagine like a sphere where you have like a bunch of cameras on the inside of it, and you're taking a picture of what happens at the core of it. In our case, it's actually a cylinder because the beam comes in from the side. And then we have a cylindrical detector, which takes pictures of everything from every angle. And there are multiple layers of cameras. We have different kinds of cameras that can do different things, measure different properties of the particles. And so we get like not just one image, we get like another image and another image.

45:18It's sort of like if you have a red filter and then a green filter and then a blue filter, you can measure different colors at different intensities. Later, you have a more complex reconstruction of what happened. So we have layers of detectors with different technologies and different abilities to help reconstruct what kind of particles came out. And are there detectors like around the entire length of the path that particles are getting shot? Or is it just like there is a region where all the detectors are and that's where you're measuring what's going on? Does that make sense? Yeah, there's a region because there's a region where the collisions happen.

45:51So the beams circulate through the whole 33-kilometer-long accelerator complex, but they only cross at certain places. And those crossings are where the collisions happen, and that's where we surround with our detectors. And the detector itself is like a cube of electronics, like 50 meters by 50 meters by 50 meters, very roughly. And what is the sound when two particles collide?

46:17Totally unreasonable, but very fair question. it happens in a vacuum and so it's totally silent. Oh, what a disappointing answer. But if I was asked to be a sound engineer for a movie in which very unrealistically a sound was made, it would sound like this. Because these are tiny little particles. And even though they sound like they have a lot of energy, it's not actually that much energy from like our point of view. I think it would sound like...

46:50So let's go through the layers of cylinders for what happens around this tiny scream. And so we said we had layers and layers of detectors. The first ones are very similar to cameras. They are just thin sheets of detectors that try to tell us if a particle went through there. We call these trackers because we want the detector to leave a trace for each particle. Like where did the particle go? So the particles fly through a very low mass material, like very thin sheets of silicon or dilute gas or supersaturated water. That's what a cloud chamber is. That leaves some kind of indication of where the particle went, but not to slow it down very much.

47:30We want to leave the particle mostly unchanged because these detectors are also immersed in a magnetic field. And that magnetic field bends the path of a particle if it's charged. and from the curvature of that particle, we can measure its momentum. So you try to figure out where was the particle going through this magnetic field so you can fit a circle to it and say, okay, this one had this much momentum, this one is curved less, so it has more momentum, that kind of thing. Okay. All right. And so that's detector number one. That's the first layer in the tracker. And that gets very, very close to the actual collision.

48:04Like the distance between the first layer detector and the collision point is like roughly a centimeter. Now, you surround that tracker with something called a calorimeter, which is a useless name. You don't need to know, and so I shouldn't have said it, but something that measures the energy, right? And the goal here is the opposite of the tracker. You want to slow it down as much as possible. You want it to smash into really high mass material so that it creates a shower of energy. One particle with high energy turns into two with half the energy turns into four with a quarter of the energy.

48:35Eventually, you have a trillion particles with very low energy. And you can measure all those particles, like how much scintillation light do they produce? There's lots of different calorimeter technologies. But in the end, you're turning one particle with a lot of energy into a shower of particles that you can measure and using that to measure the energy of the particle. But I thought the particles had already broken apart because of the smashy-smashy that happened before. But now another smash is happening when it reaches the detector? Yeah, so the particles have broken apart and they've created something new.

49:07Maybe it's a muon and it's flying out from the collision. So we're not trying to image the particles that went into the collision, the protons. We're trying to image what came out of the collisions because we don't know. And so different particles are going to leave different patterns in our detectors. But yes, we are creating secondary smashes in order to figure out what are those particles. Remember, you can't observe particles passively. You have to interact with them to know what is the momentum of this muon, what is the energy of this muon. And in this case, we want the muon to smash into a block of copper and leave its energy there so we can measure what the energy of the muon was.

49:42Okay. And does this get used up as you use it? Because once you smash into the copper, does that mess up the copper atoms? And then do they have to be replaced eventually? It doesn't mess up the copper atoms. No, it gets them a little warm, right? And then they cool down. What does get messed up is the tracker. It's very close to the collision and it's much more delicate. it. And so after a couple of years of running in a very high radiation environment, it just gets trashed and we got to pull it out and build a new one, usually a better one, because by then the silicon technology has improved and we put in a new, faster, more robust, higher resolution one.

50:19But the calorimeters are pretty solid. You can use them for decades and then you can use them in another experiment. We'd like to build them out of high Z material like depleted uranium or sometimes even lead or steel, but we like them to be low activity. And sometimes we even reuse material. Like some of the detectors I worked on for my PhD were refashioned from old Soviet battleships. What? Because that was like old steel. And so it was like radioactively quiet. Yeah, cool stuff. That's awesome. Yeah, exactly. So we have these basically two layers, the tracker and then the calorimeter. and then at the outside we have another tracker for anything that escaped the calorimeter, anything that didn't leave a splash in the calorimeter, we try to get a record of that as well.

51:03Oh, and we have two kinds of calorimeters. One that's really good at making like electrons and photons make a splash and another kind that's really good at making particles that have the strong force make a splash. So then we have overall four rough categories of detectors, a tracker, two kinds of calorimeters, and then another tracker. And then we play the magic game When a particle goes through, we see where did it leave a track? What did it interact with? What is its pattern? And then from that, we can tell what it was. So for example, an electron will leave a track in the inner tracker because it has a charge.

51:37And then it will make a splash in the first calorimeter and usually not make it to the second calorimeter. So that's what an electron looks like. A photon looks exactly the same. It makes a splash in that calorimeter, but it does not leave a trace in the tracker because it does not have a charge. And you have to have a charge to leave a trace in that inner layer. So that's how you tell photons apart from electrons. Okay. Yep. Got it. And protons look like electrons, except they don't leave a splash in the first calorimeter. They leave a splash in the second calorimeter. Muons hardly leave any splash.

52:12They make it all the way through because they're more massive than electrons. And they leave a track in the outer layers. Neutrinos leave nothing at all. And so by playing this game of like, where did you leave a trace? How much energy did you deposit here or there? We can figure out what kind of particle each one was. So then we have this multi-layer, every direction digital camera to image every collision and then reconstruct what we think happened from it. Do you ever wonder to yourself, okay, we know what we want to look for for particles we're familiar with, but like there might be particles out there that we've never seen.

52:47and so we might not be detecting them at all because we don't have the right kind of detectors. Does that keep you up at night? Why are you dreaming about being a pizza when you could be worrying about this? Oh, absolutely. I wonder if there are particles out there that we can't detect or if there are particles out there that leave unusual traces in our detectors so we're not looking for them. That's actually like a big part of my research project over the last few years has been using machine learning to try to reconstruct unusual particles, particles we don't anticipate. Because you're right, the strategy I just laid out for you is like, here's how you see the particles we do know.

53:27But these are computer programs, which means they're dumb. They follow your instructions. If they see something weird, but that's obviously a new particle, they would just reject it. They're like, that's not an electron, moving on. That's not a muon, moving on. So together with my students, we wrote a program which could identify unexpected particles, things that move smoothly and leave some kind of obvious pattern, but not according to any of these categories. Awesome. Yeah, that's definitely something I'm excited about. Yeah, I feel like this is what we're going to be talking about when we're doing your Nobel Prize acceptance speech episode.

53:59You're not going to do the acceptance speech on here. But anyway, when you're telling us about getting the Nobel Prize. You know what? If I win a Nobel Prize, I will live stream it for the pod for sure. Great. And I do not think that I'm going to win a Nobel Prize, but I do like to do research that has that possibility, where there's like a small chance that we really are going to find something totally revolutionary. I don't like to do research where like, well, we basically know the answer. We just need to measure it a little bit better. I like swinging for home runs. You're mostly going to miss.

54:27I've never hit, but at least I swung. That's right. That's right. At least you swung. And I hope that when you make it big and you actually hit that ball, you remember us little people over here at DKU. That's going to be my favorite podcast episode when we do that one. All right. All right. Let's send this response back to Eric and see if we answered his question. Thanks for digging into how particle accelerators detect particles. You always mention that questions are welcome, but I think Kelly asked questions along the way that I had thought of, and you addressed all of them. So thanks very much.

55:00Especially love to hear that people are thinking about that you've worked on how to detect things that you can't detect, which I think is a really cool research avenue. Thanks a lot.

55:14Well, we have an exciting bonus question for everyone today. We do indeed. I'm very glad to be able to sneak in an extra fourth question. And this extra question is from Lucas, who's nine years old and already thinking about the universe. Hi, my name is Chad from Atlanta, Georgia, and I have my nine-year-old son who's interested in science and physics. Hello, I'm Lucas, also from Atlanta, Georgia, and I want to know what you think about the universe in a black hole theory. More specifically, how can we use current physics to either prove or disprove the universe in a black hole theory, and how did we get into this?

55:52Thank you. Thank you very much, Lucas, for your question and to Chad for thinking about physics with your kids. Love to everybody out there who is raising the next generation of scientists. Talk to your kids about parasitoids, people. Only if you want to be holding them crying at 3 a.m. Then you get to hug them. All right. We are far from the topic of Lucas's question here. Lucas is asking about this question about whether the universe is inside a black hole. And this is something we've talked about a few times on the pod, so I'll just recap it quickly for you. It's fun to think about the universe as being in a black hole because everybody wants to know what's in a black hole.

56:31And it would be amazing if the answer was this. We are in a black hole. Oh, my gosh. Then we would know, right? Super fascinating and super fun. And there's reasons people think about this. There are superficial connections between our universe and a black hole. Like some theories say that our universe began with a singularity. and we think that there's a singularity inside a black hole. So like, hmm, that seems similar. But those two singularities are very different. The singularity that people hypothesize is that the beginning of the universe is a moment in time when everything was very, very dense everywhere.

57:05And the singularity at the heart of a black hole would be eternal. It would last forever, but would be at one point in space. So the Big Bang singularity is everywhere in space and a moment in time. the black hole singularities everywhere through time, but at a point in space. It's already quite different. Yes. So it sounds like you're saying no. But there are other reasons people think it, like there's the horizon coincidence. We know the black holes have an event horizon, and our universe has a kind of horizon. There's a point beyond which you cannot see because life has not had enough time to get to us from there, so we can't see past there.

57:44Those seem like they kind of overlap. And even more than that, if you add up all the mass in the universe and ask what would be the radius of the event horizon of an object of that mass, you get roughly the length of the cosmic horizon. So you're like, hmm, well, that kind of seems like maybe we are in a black hole. But that calculation assumes that you're in an empty, non-expanding universe. So if you had an empty universe that was not expanding and you put our universe amount of stuff into our universe size bubble, then it predicts you would get a black hole. But we don't live in an empty universe.

58:22There's stuff beyond us and we are in an expanding universe. So that calculation is not valid. It's just kind of a cosmic coincidence. So there's no evidence that we're in a black hole. There are kind of a couple of superficial coincidences that hint in that direction. but they fall apart when you look at them more carefully. All right. Well, now Daniel has had his opportunity to be a wet blanket.

58:48All right. Thank you very much, everybody, for sending us your questions, for sharing your dreams, your nightmares, all of your curiosity with us. Yes. Please send your questions to us at questions at danielandkelly.org. We answer every email. Daniel answers them in like 30 seconds. I take a few days. And some of them even end up on the show. All right. Have a wonderful science-filled day, everyone. Even the ladybugs and the cockroaches. Good luck.

59:22Thanks, everybody, for listening. Please go and do us a favor and rate the show on whatever podcast app you're using. It really helps people find us. Daniel and Kelly's Extraordinary Universe is edited by the amazing Matt Kesselman. He really is a wizard. You can also find us online on Blue Sky, Instagram, and XDNKUniverse. Come engage with us. You can email us at questions at danielandkelly.org. We really do want to hear from you. And you can find our website, www.danielandkelly.org, where you'll also find an invitation to join our Discord, where everybody comes and talks about the amazing universe.

1:00:01And we also have the most amazing moderators. This is an iHeart Podcast. Thanks for joining us.

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