Relativistic beaming

24:00But they're not stars, right? They're not stars. So it was good that they left that fuzz. Oh, so stellar means star, not just like spacey. Yes, exactly. Something like a star. Yeah. Yeah. Kelly is really good with words. All right. Moving on. And they knew that they had a very small angular size, right? They could tune the radio telescopes in a certain direction and see it and then turn it a little further away and not see it. And so you could tell that this thing was coming from a localized spot in the sky. And by the 60s, there were like hundreds of these things had been cataloged. And so people started a dedicated search for like, let's look to see if we can find something that corresponds to them.

24:41And then in the early 60s, they finally found one. They found what looked like a faint star right at the location of the radio source. But the spectrum of it didn't really make sense. It was very confusing to understand what this object was. What was it? It was the quasar. But then what is a quasar? And what is a quasar? That was the question, right? So first thing they did is look at the spectrum, and they noticed like, hmm, this spectrum implies that it's really, really, really redshifted, meaning that it's really, really far away. Because remember, as we look out into space, we're not just looking back in time.

25:15We're looking at things that are moving away from us. Hubble's big discovery was that the further away something is, the faster it seems to be moving away from us. And so if you find something which is super redshifted, meaning it's moving away from us very fast, that also means it's super distant. And that was one of the early puzzles. It's like, okay, we're seeing this star. It's not super bright, but it's crazy far away, which means that at its source, it's got to be like insanely bright for us to see it. These things were apparently like most of the way across the universe. And yet somehow we were still seeing them.

25:49So people were like, what? This doesn't make sense. If our calculations are correct, there's an incredible source of energy being shot at us from across the universe. How can that be right? Yeah. How can that be right? It's like a murder mystery. I'm waiting for the end. Yeah, exactly. And so you have this combination of extreme velocity and distance, yet we're able to see it. And this implies some intense source of power, right? You need something in order to generate, something to make these things brighter. Essentially, it would have to be like a thousand times brighter than the entire Milky Way for us to see it across the universe.

26:27So we're talking like three billion light years away. And so the early explanation was that you have an active galactic nuclei. So the centers of the galaxies are not just like, here's a bunch of stars all swirling around. And they're just sort of denser than they are out here. but that there was something else going on. And this is essentially at the same time as we're starting to understand, hey, are black holes a real thing? They're not just like a calculation that Einstein and his friends did. Are they an actual thing out there in the universe? And so this all came together into this cohesive explanation that the center of the galaxy is very dense gravitationally, and you have these supermassive black holes at their cores, and the gravity of that supermassive black hole combined with its magnetic field is generating these astrophysical jets.

27:18Okay, so a quasar is the center of a galaxy where you have a black hole and all of that denseness and stuff is shooting out. Yes, exactly, as seen from Earth. So like you could describe it in several ways. You could say you have an active galactic nucleus, which is generating these jets from Earth. If you see it, you call it a quasar. And so it's sort of the union of these things as seen from different angles. So does every galaxy have a quasar? No, every galaxy does not necessarily have a quasar. What? It's fascinating. Not every galaxy has an active nucleus, right? It's really interesting. And is that because not every galaxy has a black hole at its center, maybe?

27:56Or this is a different reason? We don't know. It's a real mystery. It seems like the universe made a lot of quasars about 10 billion years ago. And since then, it hasn't been making very many of them. So like that's why most of them are far away. Like there aren't quasars that are like quasaring right now nearby. Like the Andromeda doesn't have a quasar. It doesn't have massive bright poles of plasma shooting out from both sides of it. You have to look further away, which implies that it was in the past. So there was something in the conditions of the universe 10 billion years ago, which was really quasary.

28:30And it's no longer is the universe very quasary. It's like the fashion of the universe. Like neon leggings were big in the 80s and quasars were big at some point, but both went out of style. Yeah, exactly. But the leggings are coming back. Maybe quasars will come back. Maybe quasars. Yeah, nostalgia for the early universe. I don't know. These things are dangerous, right? So it's crazy. The oldest quasar we've seen comes from a galaxy we visualized 690 million years after the Big Bang. So that's less than a billion years after the first atoms are formed and then finally stars are formed and then galaxies come together and already you have the conditions necessary to create a quasar.

29:14And this is one of the bigger puzzles in the early universe recently is like how things got so big so fast. How did you get supermassive black holes at the centers of galaxies so quickly after the beginning of the universe? Our simulations can't explain that. James Webb Space Telescope, which looks in the infrared, can see super distant, super old stuff. And it's visualized galactic formation that nobody understands either. Like very early in the universe, you have galaxies that are much bigger than anything we can understand. So this is a core question. It's like, how does stuff come together and form structure in the early universe so quickly?

29:49There's definitely an element there that we don't understand. And quasars are a big part of that. Why did they come up in the early universe? Why aren't they making them anymore. Why did they go out of style like the fashion in the 80s, which I would say was a really good era. So, okay, so the jets are different than the quasars. The jets come out of the quasars. And so why are the quasars making the jets? Yeah, I would say quasars are the thing we see from Earth, right? The jets are the sort of underlying physical process that generates our observation of the quasar. But you're right. It's a good question.

30:21What is making these jets? They're super bright. They're super intense. We think they're powered by this active galactic nuclei and fundamentally the black holes at their cores, right? These are super massive black holes. And remember, black holes come in two categories. There's like, there's a star that burned up all of its fuel and the fusion is no longer providing pressure to keep that star puffed up. And so the gravity eventually wins and it collapses and you get a black hole. That's going to give you a black hole up to like 50, 80, maybe 100 times the mass of our sun. But the black holes at the centers of galaxies, these things are like millions or billions of times the mass of the sun.

30:59So definitely not the collapse of an individual star. And again, a big mystery as to how they form, but they're enormously massive and they're at the centers of these galaxies. And we think that the gravitational energy of these black holes, as well as their spin, is what's powering these astrophysical jets. All right. So as a biologist, it's counterintuitive to me because I feel like the main thing I know about black holes is that they like suck things in if it gets close enough. And so now we're talking about stuff getting seemingly spit out of black holes. So what bridged the gap there for me?

31:33Yeah, it's a good question. And remember that black holes are super gravitational and powerful, but they're not magical, right? They just like suck everything in. You can, for example, orbit a black hole the way you can orbit the sun, because the gravity from a black hole is just gravity. So if you're at the right velocity and at the right radius, you can orbit a black hole forever. It's not going to magically suck you in. So let's think about how black holes at the centers of galaxies work. You have the black hole, then you have stuff swirling around it, right? So that stuff could, in principle, stay in orbit forever.

32:05So just because it's near the black hole doesn't mean it's going to get sucked in necessarily. And that's why you have like this accretion disk. If you think about your image of a black hole, it's not just like a black sphere. There's like a disk of stuff that's orbiting around it. That's the stuff that's like on deck for going into the black hole hasn't fallen in yet. All right. So why does it actually fall in? It falls in because there's friction. Like if you're just orbiting a black hole or a star, you could do that forever. But if you and 10 trillion of your friends are all orbiting a star, you're going to bump into each other and occasionally somebody's going to get nudged into the center, right?

32:42Out of orbit. That's what an accretion disk is. It's like a huge cloud of gas and dust and little bits. And there's friction between them. They bump into each other. They pull on each other gravitationally. So some of this stuff falls in. All right. So particles are now falling in towards the black hole, but black holes also have magnetic fields. They're not just gravitational objects. And what do magnetic fields do? They bend the path of charged particles. Think about particles coming from the sun towards the earth. What happens to them? They don't just hit us down here on the earth. They get deflected by the magnetic field and they get deflected towards the North Pole and towards the South Pole.

33:21And some of them, because the magnetic field is different at the North Pole, go into the atmosphere there, which is what causes the Northern lights or the Southern lights. Those are super high energy particles from space hitting the atmosphere and then glowing. Gorgeous. Yeah. And so just like the Earth has gravity but also has a magnetic field, particles falling into the black hole will get deflected up towards the North Pole or the South Pole because of the super intense magnetic field. And so they get sped up by the gravitational field and then they get bent by the magnetic field and then shot up or down the poles.

33:54Ah, okay. So everything that's getting shot out then has some charge. Yes, almost everything here is going to be charged because it's very hard to stay neutral. Like if you have protons and electrons and they're in hydrogen atom, the energy of that bond is tiny compared to the energy of these particles. And so they're just going to blow apart, right? So basically everything is plasma here. Everything is charged. And so you get plasma that gets shot up and down the North and South poles and plasma itself glows. So where do the photons come from, right? Photons come from these particles getting bent by the magnetic fields because how does a charged particle change direction?

34:28every time a charged particle changes direction, it emits a photon. That's the only way you can do it. You can't just be like, I'm going this way, now I'm going that way. The way it does it is by emitting a photon. It's like, I'm going straight, I wanna go right, I'm gonna emit a photon to the left, therefore I'm gonna recoil against it to the right. Just like if you're flying through space and you wanna change direction, what do you do? You fire your rockets and you shoot some stuff out in the opposite direction that you wanna go. Charged particles have to do that also. and they shoot out photons.

34:59They have like an infinite supply of photons inside of them. You can imagine they don't literally have all those photons. They just, you know, dump some of their energy into the electromagnetic field with momentum in the opposite direction that they need to go. And so then they go that way. And there's nobody like driving these particles. I'm making them sound like they're making these decisions, but this is just the process. Anyway, so stuff falls in towards the center, gets routed towards the poles using the magnetic field. And that's how you get these jets. And the power comes from the gravitational energy of the black hole.

35:32So the centers of galaxies that have astrophysical jets are only the centers of galaxies that have a black hole in the middle. Is that fair to say? Because you need the black hole's magnetic field? Yeah, exactly. Okay. And that's because almost every single galaxy has a supermassive black hole at its heart. Okay. So it's pretty safe to say anyway. And do all black holes make these jets? Yeah, that's a great question. And so some of these active galactic nuclei have all the conditions we think for making a jet, but they don't have jets, right? There is a big powerful black hole there. There's a swirling mass of gas and dust and particles, but there's no jet.

36:11And so as we said earlier, this is not something we currently understand. And there's a lot of current research on understanding the magnetic environment around a black hole. Because it's fun to even think about, well, why do black holes have magnetic fields anyway, right? Aren't they gravitational objects? Yeah. Why? Black holes are really weird things, and there's only three things that they can have. They can have a mass, right? You can put stuff into a black hole and it grows, so its mass increases. But they can also have an electric charge, right? What happens if you have a black hole and it's neutral, and you drop an electron into a black hole?

36:48Well, now it has a charge because the universe conserves electric charge. It can't just eat the electric charge and then boom, it's gone. You've deleted it from the universe. The universe conserves electric charge. So if you drop an electron into a black hole, we don't know what happens to that electron. Is it still an electron? Whatever. Is it something else? But we do know that that charge is now added to the event horizon. So we don't know what's going on inside the black hole, but you can think of the event horizon itself now as charged. So do most black holes have a negative or a positive charge or is it like split 50-50?

37:21What is the predominant charge of black holes? Yeah, great question. Most black holes have either a positive or a negative charge. It's about split 50-50. We think. We haven't measured this in detail for any black holes. But, you know, imagine that you randomly throw in positive and negative particles and you do it a billion times. In order for the black hole to be neutral, those would have to be exactly equal. It's like flipping a coin a trillion times and getting exactly half of them to be heads and exactly half of them to be tails. Very, very unlikely. So we think there probably are no electrically neutral black holes in the universe.

37:58Probably every black hole out there has some charge because it's eaten positives and it's eaten negatives. And the chances that they add up exactly to zero, basically zero. So now you have a black hole has gravity, has mass, and has electric charge. There's one more thing black holes can have, which is spin. because the universe also conserves angular momentum, right? Momentum is just like if you're moving through space, Newton tells us that you can't just move without something pushing you or this conservation of momentum. Well, spin is also conserved. If you like set something spinning in space, it'll spin forever.

38:33The only way to stop is to come with some external torque. Same thing is true if you drop something into a black hole. Instead of just dropping an object straight in, imagine if you drop an object so it hits the black hole like sort of near the edge, sort of like spinning a bicycle wheel, right? Pushing on the edge to make it spin rather than poking it in the center. Same thing. If you drop an object into a black hole, you can make it spin and it conserves that spin. The universe can't just get rid of angular momentum. So now you have an object which has an electric charge and it has a spin. What happens with that?

39:05You've got a magnetic field. Boom. Oh my gosh. Congratulations. Woo! POD in physics. Exactly. And because magnetic fields are not generated by magnetic charges, we don't know if monopoles exist in the universe, right? The only way to make a magnetic field in our universe is to combine electric charges and motion. So currents generate magnetic fields, spinning objects generate magnetic fields. So black holes have magnetic fields. And this is fun to think about. The way I visualize it is that I put the charge and spin on the event horizon. We don't know what's going on inside. This way you don't have to worry about, like, how is the information getting from inside the black hole to the outside?

39:46Just imagine a spinning sphere of charge, and that generates a magnetic field. And Event Horizon is conceptually similar to that. Okay, so all black holes, it sounds like, all black holes should have magnetic fields because probably none of them are neutral. Exactly. But they don't all make the jets. Is that because some of them have stronger magnetic fields than others, or we really don't know? We really don't know. Yeah, it's a mystery. Active galactic nuclei, hot area of research, and definitely not something we understand. But, you know, when they do this, it's really dramatic. One other way to study these things is not to look for the active galactic nuclei, but to try to study the black holes and their magnetic fields in more detail.

40:28And so, for example, we have image black holes, a couple of them, right? Remember these pictures that look like a Krispy Kreme donut of the accretion disk around a black hole? Super awesome from the Event Horizon Telescope. That's the stuff that's swirling around the black hole waiting on deck maybe to go in. Well, a few years after they released that image, they released a follow-up image where they studied the magnetic field lines near the black hole By looking at the polarization of the photons that come from different parts of the accretion disk, they can understand the magnetic fields. And polarization of photons is kind of weird.

41:03It's because photons are vector objects. They're not just like a location in space. They also have like a direction. And so they can essentially spin as they move. And so photons have like this little vector, extra vector that you can measure. We don't have to dig into the details now. But we are studying the polarization of these photons that come from the vicinity of black holes and trying to understand which models of magnetic fields in the vicinity of black holes make the most sense, best agree with the data, with what we see out there in the universe. Cool. All right. So let's take a break.

41:37And we've talked about astrophysical jets. And I realized that in my head, I've decided that that is what relativistic beaming means. But maybe that's not actually true. So let Daniel shake in his head no. So let's clear up Kelly's misconceptions after the break.

42:18Another Rihanna. To soul food, memory, identity, and the stories we carry through Black culture. What does it mean to be Black and eat in America? So we were this group of people who knew how to work the land, who knew how to live with the land. We make it do what it do. Therapy for Black Girls is bringing together the conversation shaping Black life right now. You will never make me feel bad for being a Black girl, for being a Black American girl, ever. Therapy for Black Girls is bringing it all to the mic. Listen to therapy for Black girls on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts.

42:51I'm Munga Shatikula, and I'm back with a new season of the podcast Skyline Drive. This time I'm diving into a rabbit hole of peptides, organoids, blood boys, blue zones, and brain replacement to try to understand what this longevity obsession is all about, and what it really means to live forever for all of us. I learned about some rad science. I can make a brain for you, and then we can test what draw is the best for your brain, as opposed to his brain. Here's some hard truths. I would expect Indians to age faster, but I did not expect it to be almost a four to five year acceleration. And get myself into a world of trouble.

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44:12of Obsession. On set, there was so much magic happening with each scene we were putting together. Deep dives into classics like 2001 A Space Odyssey or Fight Club. We are being denied the information about who Tyler Durden is because the narrator is being denied that information by himself. Plus weekly episodes on all industry news. Listen to Raiders of the Lost podcast on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts. And for more, follow at Raiders of the Lost Podcast and at TikTok Podcast Network on TikTok. You said to me, yo, you know, keep at it because you let me rap for you.

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45:56Alright, so astrophysical jets are those things that get shot out of quasars that have black holes, but not all of them. And I thought that this resulted in relativistic beaming, like the beam that comes out of the center. But no, you shook your head no. So what is relativistic beaming, Daniel? Yeah, so we have these astrophysical jets. We understand something about how they're made. They're extraordinarily powerful. We used to call them quasars when we saw them in the sky. And we see them all over the universe. There's lots of them that we've spotted. We've, I think, identified 750 ,000 different quasars in the universe, which is a lot.

46:35Most of them are not pointed at us, right? So we can see them even if they're not pointed at us. And the most dramatic pictures you'll see online are ones we see sort of from the side. We can see them from the side because they emit photons also from the side. They hit each other and they glow, et cetera, et cetera. But the brightest ones are the ones pointed right at us. Like if there's a galaxy out there that's oriented perfectly, so we're looking at exactly at the plane of the galaxy and the core of the nuclei is pointed like directly at the Earth, then those particles are shooting exactly towards us when they're emitted from the galaxy.

47:10And then they benefit from a super awesome extra special boost that makes that galactic core even brighter than it otherwise would be. And that's relativistic beaming. Ah, okay. So it's not brighter just because it's pointing at us, making it easier to see. It's brighter for some other reason? That's right. It is brighter because it's pointing at us and that makes it easier to see. But plus, it gets souped up because of this relativistic effect, which you could also consider to just be like the relativistic version of the Doppler effect, right? Anything that's moving towards you is going to get blue shifted.

47:46Anything moving away from you is going to get red shifted. And it's easy to understand that. It's something we experience every day. If you hear a police car drive by you, you hear the sound that its siren makes changes as it passes you, right? When it's approaching, it's a higher sound. When it's moving away, it's a lower sound. Why is that? It's because the wavelength gets shifted to longer wavelengths when it's moving away from you, right? And if you just imagine like a source moving away from you, it's going to draw out longer wavelengths than a source moving towards you. And so each wavelength is a little bit shorter.

48:19That's the generic Doppler effect. Things moving away from us are redshifted, which is also how we can infer distance because there's a relationship between redshift and distance in the universe. Things moving towards us are blueshifted. And we see this in the sky. Not everything in the sky is moving away from us. Andromeda, for example, is overcoming the expansion of the universe. Local gravity is pulling it towards us. So Andromeda in the sky is blueshifted, not redshifted. Okay, so that's the Doppler effect, which is something fairly well known. But special relativity changes everything, right?

48:50Normal Doppler effect is what happens when things are pretty slow and not moving super fast, like the way I move here on Earth, right? Especially now that I'm 50 years old. You're a spry 50, Daniel. Thank you. You're welcome. Astrophysically speaking, I'm quite young. That's right. These quasars make me feel like a spring chicken. But when relativity comes into play, things change. And astrophysical jets are moving near the speed of light relative to us. And so they benefit from the relativistic Doppler effect, which super enhances the brightness in the direction of motion, the energy of these things in the direction of motion for two reasons.

49:30Reason one. And reason number one is our old friend length contraction. And the rule of thumb for length contraction is moving objects seem shorter. So if you're just like looking at a ruler and it's sitting next to you, you measure it's a meter long. If instead it's zooming towards you at nine tenths the speed of light and then you measure it, you're not going to measure it to be a meter long. You're going to measure it to be less than a meter. Moving objects are shorter. Okay. And that's a super fun and mind-bending consequence of special relativity, which I love thinking about. And people often ask me, like, well, why is it shorter?

50:07And, you know, I think that's a really revealing question because the answer is it only actually makes sense for it to be shorter. in a universe where the speed of light is fixed for all observers, it has to be shorter. It wouldn't actually make sense to measure that meter stick as a meter if it's moving. But our intuition is that speed shouldn't change the length of things. Kelly thinks, oh, when my daughter's running across the yard, she's the same person, the same size as she was when she was standing still. And mostly she is, almost she is, you can't tell, which is what gives us this intuitive feeling that length shouldn't depend on velocity, but we're wrong.

50:45It actually does. There's no good reason why length shouldn't depend on velocity. So this question like, why does length depend on velocity reveals again, just our bias towards things we find intuitive. If I told you, oh, length doesn't depend on velocity, you wouldn't ask me why. You'd just be like, yeah, cool. Makes sense. Anyway, that's a digression on special relativity. But in this case, what's happening is the thing is shooting right at us, moving very, very high speeds, right? So from the point of view of that object, the distance between it and the Earth is contracted, right? Because it sees the Earth moving towards it at really high speeds, right?

51:25So we're seeing it as if it was closer, right? So relativity is like shrinking the distance between us and the center of this galaxy, this furnace where the black hole is shooting bullets at us at super high speed. It's bringing us closer to that. And that's what makes it brighter. That's one of the things that makes it brighter. Crazy. That's reason number one. And that's why it's called relativistic beaming, because it's like the relativistic Doppler effect is making this much brighter if it's pointed at you. That's amazing that we figured that out, because you'd look out at the sky and you'd be like, some quasars are brighter than the other.

51:56But like to account for that. Anyway, go humans. And that's why I started this episode with like, to understand this, you've got to understand gravity of black holes. You've got to understand magnetism of the bending. And then you've got to bring in the relativity to show why these things are so bright. So many blocks. All right. Reason two. Reason number two is the other fun bit of special relativity, which is time dilation. Right? So special relativity tells us that moving objects look shorter, but also that moving clocks run more slowly. Right? Mm-hmm. And so what's happening when you're looking at a quasar is relativity changes the frequency of these things, right?

52:34We talked about how you go from redshift to blueshift, depending on the velocity. Well, changing the color, changing the frequency also changes the energy, right? And so if these things are blueshifted, that makes them more energetic. So the particles are not just pointed at us, they're moving at us at very high speed. And relativity boosts that to make them have more energy in our frame. And that's a confusing thing to think about, like, how does relativity give something more energy? Remember that energy is conserved in a static universe. It's not actually conserved in our expanding universe, but it's not invariant.

53:09Meaning like I can measure the energy of something and you can measure the energy to be different. If your daughter is running past you on the lawn, you measure her to have a certain velocity, a certain kinetic energy. If your husband is running next to her, he says, no, she's not moving at all. She has no energy. So you two can disagree on how much energy she has because energy is frame dependent. We think it's conserved in a static universe, but it's not invariant, which often leads to confusion. So you and I can disagree about how much energy something has. And the energy of these astrophysical jets depends on the observer because energy is frame dependent.

53:44It's relative. It's not an absolute quantity. Okay. Okay. And so while you were describing this, I realized that. So we're talking about charged particles moving super fast towards us. Is this galactic cosmic radiation? Is this what the astronauts have to worry about? This is one source of that. Absolutely. Yeah. And when you're out there in space near the ISS, for example, this is one of those elements. You're absolutely right. It's a dangerous environment. And that partially comes from the sun and partially comes from inside our galaxy and partially comes from other galaxies. We think the highest energy ones come from the centers of other galaxies.

54:20Whoa. Okay, so I should be saying that galactic cosmic radiation comes from quasars? No, from astrophysical jets. Or quasars, yeah. Either one works. Okay, and they're super bright because of relativistic beaming. Yes, absolutely. They're super bright even without the relativistic beaming, but then they're super double extra bright because of the relativistic beaming. The ones that are pointed right at us get super enhanced because of these relativistic effects. So it's this incredible dance of all these pieces of physics. And it took us decades to put this all together. And so many different branches of physics and so many different historical traditions came together for us to start to understand a coherent picture of what's going on inside galaxies.

55:01And that's such an important thread in science, is understanding things from different perspectives and making sure the story you're telling is coherent when you come at it from different angles. And that's often how we unravel mysteries, right? And we're like, well, this seems to work, but wait, what about this piece? If I measure it differently or if I come out from this angle, it's not making sense. Because we think, we hope the universe does make sense and that there is a story out there that we can unravel no matter how you look at it. And I really love human stories. So let me tell an astronaut story really quick.

55:32So when I was reading astronaut memoirs, there's a lot of times where they'll talk about like being in space and then like a flash of light. It's like it passes through their eyeballs. and they were kind of not sure what it was. It's probably kind of a scary experience. And I think that the main hypothesis to explain what's happening is that galactic cosmic radiation is passing through your eyeballs and it like lights up, you know, the receptors in your eye. And that's what you see. It's kind of scary. Yeah. One, super scary. Two, kind of amazing though, to think that your, you know, vision is being impacted by something happening in a quasar on a distant, you know, galaxy.

56:12Anyway, what a crazy universe we live in. Also, I like it down here on Earth. I know. It is nice to live here beneath the shelter of our magnetic field and our atmosphere, where our eyeballs are not getting pelted by bullets shot out by black holes from other very distant galaxies. Thank you, magnetic fields, protecting our Earth. Thank you, our fragile environment. And thanks to everybody out there for being curious about how the universe works and listening to this explanation for how the centers of distant galaxies combine gravity, electromagnetism, and relativity to shoot particles at you.

56:49See y 'all next time.

56:57Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio. We would love to hear from you. We really would. We want to know what questions you have about this extraordinary universe. We want to know your thoughts on recent shows, suggestions for future shows. If you contact us, we will get back to you. We really mean it. We answer every message. Email us at questions at danielandkelly.org. 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 &K Universe. Don't be shy. Write to us. He's dribbling the ball with everything on the line.

57:37He's driving down the pitch. He's facing price hikes and cuts past him. Carrier Contracts tries to block him. Oh, he leaves him in the dust. He's at the edge of the box. He cuts past the nonstop group chat trash talk. He clears on goal. He shoots. No! Unlimited data for$25 a month forever. Visit your local Boost Mobile store today to get unlimited data with a price that never changes. Boost Mobile. After 30 GB, customers may experience lower speeds. Customers will pay$25 a month as long as they remain active on the Boost$25 Unlimited plan. I'm Mange Shachigular and I'm back with a new season of my podcast Skyline Drive.

58:10This time I talk to scientists, biopunks, curmudgeons, blues owners, super seniors, and Goa's top cryotherapy lab to try to understand this obsession with living forever and what it means for all of us. And I get into a bit of trouble along the way. I'd say probably start bone smashing. That doesn't work. Make it look more defined. They say it works. I don't know. Listen to Skyline Drive, How to Live Forever on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts. When Democrats are messing up, I say it. When Republicans are messing up, I say it. I'm Essie Kupp, a journalist and political commentator.

58:45And on my podcast, Off the Cup, I help you make sense of the often nonsensical news. I do this on cable news too, but on my podcast, I can really let loose and be my honest, unfiltered self. I just want to talk about something that happened this week because it's so bonkers, so stupid, Such incredibly bad politics. We have to talk about it. Come for the hot takes. Stay for the sanity. Listen to Off the Cup on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts. From daily news to dating fails, conspiracy theories to cooking with celebrities who can't actually cook, Amazon Music's got the most ad-free top podcasts ready to entertain, included with Prime.

59:32This is an iHeart Podcast. Guaranteed human.