Daniel and Kelly’s Extraordinary Universe - Listener Questions 5

Episode Date: August 20, 2019

Daniel and Jorge answer questions from listeners, like you! Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

This is an I-Heart podcast. I was diagnosed with cancer on Friday and cancer-free the next Friday. No chemo, no radiation, none of that. On a recent episode of Culture Raises Us podcast, I sat down with Warren Campbell, Grammy-winning producer, pastor, and music executive to talk about the beats, the business, and the legacy behind some of the biggest names in gospel, R&B, and hip-hop. Professionally, I started at Deadwell Records. From Mary Mary to Jennifer Hudson, we get into the soul of the music and the purpose that

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where we get to the bottom of questions like that. Why are you screaming at me? I can't expect what to do. Now, if the rule was the same, go off on me. I deserve it. You know, lock him up. Listen to No Such Thing on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. No such thing. Betrayal Weekly is back for season two with brand new stories.

The detective comes driving up fast and just like screeches right in the parking lot. I swear I'm not crazy, but I think he poisoned me. I feel trapped. My breathing changes. I realize, wow, like he is not a mentor. He's pretty much a monster. But these aren't just stories of destruction. There are stories of survival.

I'm going to tell my story and I'm going to hold my head up. Listen to Betrayal Weekly on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Hey, Naomi, do you get your podcasts? Oh, never. I love our listening. their questions. I just mean questions in general, like about the universe, about your personal life. Or like this question you're asking me now? Yeah, or from your podcast host partner. No, people ask me questions all the time, but it's fun to

answer them, you know? Sometimes I wish I got asked more science questions, you know? Sometimes questions are more prosaic. But about your kids? Your kids constantly pester you with science questions, too? I wish they asked more, you know, it's the occasional, like, what is a black hole look like but more often it's like can I have more dessert or how come my sister gets to use the iPad more than I do and the answer is always the same nobody knows we have no idea idea they're kind of physics questions too aren't they like they're about time who gets more time on the iPad or matter yeah who gets more dessert exactly and chaos what about you your kids ask you

science questions they do yeah pretty pretty often, I think. My kids like to read, and sometimes they kind of make connections in their head. They ask me questions. And what do you do when they ask you questions if you don't know the answer? What do you mean? You assume that I don't know the answers? I often don't know the answer, so I assume not everybody has all the answers, sure. No, well, I do my best, I guess. And mainly, I just tell them to send their questions into our podcast so that you can answer them. That sounds good. I'm glad to be your backup science parent. I mean, what's the whole point of befriending as physicists, if not to get these questions to answer?

I knew you just... Why else would you want to be friends with the physicists? I knew I felt used. Now I know why. Hi, I'm Jorge. I'm a cartoonist and the creator of Ph.D. Comics. Hi, I'm Daniel. I'm a particle physicist and a backup science parent for many people out there. And welcome to our podcast, Daniel and Jorge Explain the Universe, a production of I-Hard Radio. In which we take funny, weird, amazing, crazy things about the universe and explain them to you so that you can explain them to your kids or your parents. Or just sit them down with our podcast as free babysit.

that's right yeah so we love answering questions right daniel oh yeah it's really fun because we can think about the universe and we can talk about what's exciting for us but the most interesting is answering questions from listeners because it reveals what they understand and what they don't

and what they're wondering about what all those collective brains out there are cognating on yeah so if you don't know this already we actually answer people's questions uh if we have an instagram account a Twitter account the Facebook account

and if you post a question well first of all follow us there but if you post a question most likely Daniel will answer the question right Daniel or at least maybe one of your regrets that's right no I'll answer questions

via email or Twitter or Facebook I'll be honest though I don't use Instagram so all those people asking physics questions on Instagram are just questioning into the void sorry folks the question is does anyone use Instagram anymore now that I don't

I think the question is, who doesn't use Instagram these days? Just me, I guess. I guess just physicists. No, but it's wonderful. We hear questions from all over the world, and sometimes they're questions people just had in their minds. They wanted to know the answers to, and those were wonderful. But also sometimes the questions are in reaction to something we talked about on the show.

And, you know, on the show, we do our best to think, what's confusing about this, how do we explain this, How do we make something clear, but we never can completely succeed. So it's really nice to have feedback when people say, you said X, but then that made me wonder why. And that helps us be more clear in the future. So please, send us feedback, send us questions, send us presents, send us gags, send us whatever you like. Mostly you send us money, please. I mean, how much do you think podcasting made?

That's right. And sometimes people send us serious questions about the universe, and then sometimes people send us silly questions. Yeah, like what's been a silly question? All right, here's a question we got on Twitter from Patrick Neumann. He says, Dear Daniel and Jorge,

I've got a question that really want to get answered. How heavy would a blob or banana be of all of the photons in the sun and how big would it be? Oh, interesting. So if you took all the photons in the sun

and somehow what do you think, transforms? them into a banana or put them in a shape them into a banana? What do you think he's asking? I actually started trying to work on this question and first I thought

well how many photons are in the sun right? Like is that a number? You know and it's pretty tough but it turns out you can do a rough calculation and the sun creates 10 to the 45 photons per second. That's 10 with 45

zeros. Yeah. That's a lot of photons. That's a lot of, like, trillion, bazillionians. Yes, exactly. Beninilians. Benannians. Yeah, exactly. But not all those photons escape the sun.

You know, the sun is a huge ball of plasma. And most of the stuff that's made by the sun is then just reabsorbed by the sun. And so only things that actually penetrate and leave the sun and hit your eyeballs arrive here on Earth, that's a tiny fraction of what comes out of the sun. But anyway, let's say you had 10 to the 45 photons, okay? That's a huge amount of energy. And then his question is interesting. He said, how big would that be, right? Like if you had a pile of 10 to the 45 photons.

Right. Well, how close together can you cram them in is maybe the question. Yeah, and that's really interesting because there's no limit on how close you can cram photons together. That's not true of ordinary matter. No limit. Like electrons and other particles. These things are fermions. And fermions are different from photons and other kind of particles that we call bosons

because fermions have to have different quantum states. No two of them can be in the same quantum state. They can't literally be on top of each other. That's impossible. That's right. They have to have some difference. Like, you can have two electrons in the same level of energy in an atom, but then they have to have different spins or something different about them.

And so fermions have to be distinguishable. Whereas bosons, these are particles with integer spin, like a photon. They can be right on top of each other. They can be in exactly the same place, have the same momentum, have the same everything. I feel like the silly question has gotten a little serious. Pretty serious. Yeah. It's got some serious physics. Yeah. Even silly questions reveal something interesting about the universe.

And so you can have 10 to the 45 photons on the head of a pin, basically. Right. Or on top of each other, are you saying? Yes, exactly. All on top of each other in a tiny, tiny space. So thank you, Patrick, for sending in that hilarious question. It really made us think. And there really is some physics in that question, even in silly questions. questions. Well, we do have three questions today from listeners. And so that is the topic of today's podcast. Today on the podcast, we'll be talking about listener questions. 5.0. 5.1. 5.1. Because we just

answered Patrick's questions, so we got to add a little. That's right. We're part way through this episode already. Yeah, that's right. We'll be answering questions about electrons about space, about stars, about black holes, questions from far away and questions from surprisingly nearby. Yeah, and we might even know the answer to some of these questions this time. And if we don't, we'll speculate hilariously. All right, let's jump right into it, Daniel. Our first question today is from this really pretty cool guy, fun guy, maybe one of my favorite people, has a great dad. Yeah, so this is a question from Oliver from Southern California. Yeah.

What if our whole solar system is in a black hole and we don't notice? Wow. That's a deep question. His voice sounds a little familiar to me. Yeah, what a smart-sounding little kid. He sounds like he might grow up to be a cartoonist. Well, not if he's that smart, hopefully. So yeah, that's my son who just asked that question, and he just turned to me one day.

Well, what happened when he was reading our book? So Daniel and I wrote a book called We Have No Idea. a guide to the unknown universe, available now in Amazon.com and local books. And you can verify it's been read by at least one person since your son is reading it. That's right. That's right. He's under age, but he still counts as a person, I think. He's nine years old, and so he's been reading our book, and I always kind of wonder how much of it he's getting. You know, he's nine. He's in third grade. But he seems to be enjoying it, and he keeps reading it. And so one day he just turned to me and he asked me this question.

Right. And what do you think is behind the question? What do you think he's wondering? Explain the question to me. You mean explain my son? Do a deep dive. If I knew that answer, Daniel, if I could explain my son, my parenting experience would be so much easy. No, I thought it was really interesting.

One part of his question says, what if our whole solar system is in a black hole? Cool, fascinating. But then he says, and we don't even notice. Like, I think that taps into, you know, is the universe different from how we expected? Is it possible that we think we're living in universe X but we're actually living in universe Y?

You know, I think he was probably kind of reading about black holes and he just kind of wondered like what if we're inside of a black hole? Is that possible? Like could the universe or like could a solar system exist inside of a black hole and, you know, we don't even know it? Yeah. And I think there's something wonderful there about the feeling that maybe, you know,

the universe could be revealed to be totally different from what you expected because that's precisely happened a lot of times in history, right? We've thought, oh, the universe works this way. Nope, it's totally different from what you imagined. And those are the best moments in physics. So to hear your son like sort of wondering if he's coming to that realization himself

or wondering if this kind of realization is the corner. That's fantastic. He's been bitten by the physics bug. So be careful. Oh, no. Is he going to be like Spider-Man? Well, that's only if he's bitten by a radioactive physicist. Okay, aren't they all radioactive by now? Well, I grew up in Los Al-Alimo, so maybe I'm especially radioactive, but I'll do my best not to bite your son. Yeah, but let's break it down. It's interesting question, and you know, something that's important to think about

is sort of the size of a black hole. Like, could our entire solar system fit into a black hole? Well, right, the size of a black hole is really, we usually consider that to be the size of the event horizon. That's the point. Right, the black stuff. Yeah, like the point of no return. If you look at a black hole, it would look like a black sort of sphere. And so the size of that sphere, that's the size of the black hole.

Yeah, yeah. And if you go past that point, you can't escape. Right. And nobody knows what's inside of a black hole, but we know how to calculate the size of the event horizon. It's determined just by the amount of stuff. stuff in the black hole. So the more mass in the black hole, the stronger the gravitational pull, the farther away it can grab stuff and never let go, right?

So the size of the black hole is determined by its mass. So how much stuff is in our solar system? Well, basically, the first approximation, our solar system is just a sun. Like the rest of the stuff in the solar system, Jupiter, Mars, me, you, hamsters, all that stuff is negligible. It's a tiny fraction of the mass of the solar system. So basically, you can ask, like, if you had a black hole with the mass of our sun, how far away would the event horizon be? Would it be out past the edge of the solar system?

Is it possible to fit a solar system in a black hole that has the mass of our sun? It's sort of the way I interpret the question. So you're interpreting the question as, could our solar system be a black hole? Yeah, exactly. Could we be inside a black hole right now? Is there enough room in a black hole with a mass? of the sun to fit the entire solar system. Oh, I see.

So could we be in a hole where the only thing inside of it is our solar system? Yeah, exactly. Exactly. Is how you're interpreting the question. And the answer to that is no, because a black hole that has only the mass of our sun, the event horizon would only be three kilometers from the center of the sun. And so it definitely wouldn't be big enough to have the whole solar system in it. Because the solar system is a lot more than three kilometers.

kilometers. It's one billion kilometers wide. So we couldn't be in a black hole where the only thing in it was our solar system. But is it possible that our solar system is inside of somebody else's black hole? Do you know what I mean? Like maybe there's a black hole out there with a lot of mass inside of it. And we are just inside of the event horizon of that black hole floating around. Yeah, that's possible, right? Let's consider that for a moment. So what if there's a really dense blob somewhere else, sort of nearby, and that makes a black hole that's big enough to encompass us, and we're inside that black hole, right? Right.

Well, that's possible, but it's difficult to imagine because such a huge mass would have a big effect on us. You know, if there was a really big mass somewhere else inside our solar system next to the sun, like an invisible huge blob of dark matter that made there enough mass so that the black hole was big enough, we would definitely notice that. That would affect the orbit of the planets. What if there was another big mass kind of far away, but close enough that we were still inside the event horizon? Well, you're talking about still really strong gravity. So it's hard to imagine having some enormously powerful gravitational attractor nearby and not having it disturbed

like the orbits of the planets or even just tossing of baseballs and all sorts of stuff. So I think if you were inside a black hole that was big enough to hold the solar system it would have to have a huge mass and that mass would definitely be noticeable it would affect the way things move on Earth would it though because you know like so our solar

system is moving around a galaxy right like a galaxy has a lot of mass and it's huge and there's a lot there's a huge black hole in the center of the galaxy but it's not really affecting us in a local level right like that gravity

is kind of spinning us around the galaxy, but it's not really changing the orbits of the planets around the sun. That's right, yeah. And that black hole in the center of the galaxy is really massive, and it's pretty big, but it's also super duper, duper, duper far away, right? Any black hole that's either near enough to include us or far away but huge enough to include us still would definitely affect the gravitational pull.

But, you know, I haven't done the calculation. There is one configuration, I imagine, though. Imagine our entire solar system, and then it's surrounded by some enormously dense sphere of material, okay? If you're inside a sphere of material, then the gravitational pull of that stuff doesn't affect you at all, right? Because it all balances out. There's enough stuff on the left to balance the stuff on the right. Just like that episode we talked about where you jump inside the earth. Once you get to the center of the earth, there's no gravitational force from the stuff around you, right?

Well, if you had to spear of super dense material surrounding the solar system, then that might be enough to create a black hole, right, that we would be inside of. But we wouldn't feel the gravitational force because it would be inside all the stuff. It'd be all around us. Yeah, that's what I mean. Yeah, but it'd have to be perfectly distributed, right? And the only reason to, there's one reason to think that's not the case, and that's that we have sent stuff outside the solar system. Like we've launched probes, and they're floating off into space, and we're watching them. And they have, like, banged up against the wall of some hugely massive blob of stuff.

But what have you expand that idea even further to encompass the whole observable universe? It is possible, then, that we could be inside of a black hole. Yeah, yeah. It's possible the entire observable universe is inside a black hole. Yes. You can't rule that out. How do you feel about saying that on a public record? I wonder if any of my colleagues are listening.

No, I think it's awesome. You would be surprised. I think it's awesome. And I think sometimes these awesome questions come from the minds of children. And that's why I hope that people are listening to the podcast with their kids, because kids ask amazing questions that make us think about things we otherwise would have totally discarded. That might actually be reality. Well, so that's the answer.

The answer is that it is totally possible that we are inside of a black hole and not knowing. Yeah. But I think our whole universe would have to be inside the black hole, not just the solar system. But yeah, that's a pretty small caveat for a yes answer to that question. Isn't that sort of a theory out there that the whole universe, like the whole universe is inside of a black hole and there are other black holes and stuff like that? Or is that pretty fringe? I think it is a theory out there and it's pretty fringe, but it's also totally possible, you know? Like we really just, we don't know what's going on inside black holes.

Are there little universes in there? You know, the inside of a black hole is totally. disconnected from the space that we live in, right? Like, there's no way to get from here to there, right? That's how a black hole works. Even light can't escape it. Not because it's like slowing down the light as it tries to leave, but because it's bent space in such a way that there's just no path out, like it's just zooming around inside

the black hole. So in some ways you can think of it as sort of like a different universe, disconnected from our space. And so you can imagine then anything that goes on in there. And when experiments can't constrain things, theorists' minds tend to go wild. And so they think about all sorts of crazy stuff that could be inside there, dancing bears or entire universes. Crazy scientists and nine-year-old boys.

Who might grow up to be crazy scientists. All right. Well, that's the answer for Oliver, son of Jorge. And I'll let him know. I'll let him know the answer. He asked a good question. He's stumped a physicist. Yeah, it's a great question.

If he was Icelandic, his last name would be Jorgeson. Yorgensen. Yorgensen, exactly. All right, well, we have two other awesome questions that we are going to answer about electron identity, I guess, is that would be the right topic? And also about dark matter stars, which sounds like a heavy metal band. Slash science fiction movie.

So stay tuned. We'll be right back. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal. Apparently, the explosion actually impelled metal, glass. The injured were being loaded into ambulances.

a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, and it was here to stay. Terrorism. Law and Order Criminal Justice System is back. In season two, we're turning our focus to a threat that hides in plain sight. That's harder to predict and even harder to stop.

Listen to the new season of Law and Order Criminal Justice System on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. I don't write songs. God write songs. I take dictation. I didn't even know you've been a pastor for over 10 years. I think culture is any space that you live in that develops you.

On a recent episode of Culture Raises Us podcast, I sat down with Warren Campbell, Grammy-winning producer, pastor, and music executive to talk about the beats, the business, and the legacy behind some of the biggest names in gospel, R&B, and hip-hop. This is like watching Michael Jackson talk about thoroughly before. what happened. Was there a particular moment where you realize just how instrumental music culture was to shaping all of our global ecosystem? I was eight years old and the Motown 25 special came on and all the great Motown artists, Marvin, Stevie Wonder, Temptations, Diana Raw. From Mary Mary to Jennifer Hudson, we get into the soul of the music and the purpose that drives it. Listen to Culture

raises us on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Imagine that you're an airplane and all of a sudden you hear this attention passengers the pilot is having an emergency and we need someone anyone to land this plane think you could do it it turns out that nearly 50% of men think that they could land the plane with the help of air traffic control and they're saying like okay pull this do this pull that turn this it's just I can do my eyes close I'm Manny I'm Noah this is Devon and on our new show no such thing we get to the bottom of questions like these. Join us as we talk to the leading expert on overconfidence.

Those who lack expertise lack the expertise they need to recognize that they lack expertise. And then as we try the whole thing out for real. Wait, what? Oh, that's the run right. I'm looking at this thing. See? Listen to no such thing on the Iheart radio app, Apple Podcasts, or wherever you get your podcasts. All right, we are back answering listener questions. And so our next question comes from Yuki from the Netherlands. And he is wondering if electrons have identity crises. That's right.

And this particular listener is something of a super fan, writing it to us on Twitter fairly often with insightful questions. And he sent me this one, and I thought, whoa, that's a good question. Let's take it online. And so here he is. Hi, Daniel and Jorge. My name is Eugene Rademacher, and I live in the Netherlands, hence the accent. I'm a big fan of your Marvelous podcast series, for it makes me understand more of physics, and it makes me think a lot about the universe in general.

After listening to your episode about quantum tunneling, the following question came to my mind. If an electron trapped in a well, say, A, suddenly. appears in well B, how can physicists tell it's actually the very same electron? I realized that I had the bowling ball, empty swimming pool analogy in my mind, when the question suddenly appeared in my well. Thanks for spending time on answering my questions. Live for now. All right. Thank you, Yugi, for saying this question and also for being a fan of the show. We really appreciate everyone listening out there. Yeah, exactly. And it's a really a wonderful question. To me, it goes to the heart

of, like, what are these particles? What are we talking about? But the way I interpret this question is, like, you have an electron over here, and physics tells us the electron can then later be over there. But his question is, how do you know it's the same electron?

Right? Because we don't have this sort of notion anymore of a classical path that you can, like, watch a baseball fly through the air. And when a baseball, you know, when somebody hits a home run, you watch it fly, you don't ask, Like, is that the same baseball or is it suddenly swapped out? But with quantum mechanical particles, because you can't observe them all the way along the path,

you just get these snapshots, you can sort of wonder, like, how do you know that's the same electron? Maybe it's from another electron down the street, right? Is this Tom or Harry or Mary or Sally? I feel like the question is, is there such a thing as an electron? Is there an electron you can see and follow it around? And it has a birth and a journey and then it maybe ends at some point. Wow, are we... Can you follow an electron around?

Are we getting into identity politics now? Should those electrons go back to where they came from? Just identity physics. Identity physics. Identity physics. Yeah, exactly. Obviously, we're not qualified to dive into those topics. You know, well, that's a, it's a famous topic in physics, and it's something that real physicists wonder.

And in 1940, this famous physicist, John Wheeler, he had this sort of moment of insight. And I don't know if he was smoking banana peels or what, but he was wondering, like, Why do all electrons behave the same way? Like, you drop an electron in the circumstance, it's always going to get repulsed in the same way. It's not like this one's got a little bit more charge and that one's got a little bit more mass. They're all identical.

They're not like scoops of ice cream, right? They all have exactly the same properties. And he had this moment of insight, he thought, wait a second, maybe there is just one electron. These are all the same electron. What? What do you mean? Like the electrons in my body and the ones in your body, they're all the same?

Yeah, yeah, sort of. And I think that's actually sort of the answer, is that the electron is not really a particle that has an identity. It's sort of like a state of mind or a state of matter, right? Because these days, we don't think quantum mechanically about particles as the fundamental basis of the universe. Instead, we think of fields, right? and particles are just excited states of the field.

It's sort of like when you look at the ocean, you know, and you try to follow a wave, right? A wave is not the basic unit of the ocean, it's the water, right? The wave is just like, you know, the ocean has got excited a little bit by the wind, and it comes and it goes, and there's more waves behind it. It's just a motion of the ocean. That's right, exactly. And so in that same way, you can think of electrons,

not as like, here's a little chunk of matter, a little, like, piece of the universe we're going to follow our, but it's just like a momentary excitation of this sort of hard to think about thing called the electron field which fills the universe and when it gets a little bit of energy somewhere you call that an electron it's not an object it's kind of a wiggle of an object yes exactly it's a wiggle of an object and you know this goes back to that other question we tried to answer is a photon a particle or a wave for example and I think I said on that podcast that it's sort of neither and sort of both, and really it's something else weird and fundamental that we just cannot understand

by making analogies, right? Analogies from our macroscopic experience, things that we're familiar with just don't work because we've never seen anything like that before. Well, it turns out you can apply the same ideas to an electron also, right? An electron is both a particle and a wave and both and neither and something else totally weird. It's really just the excitation of a quantum field. And the reason, the reason actually that we came up with quantum fields, the reason that this whole development is progress, right, and not just confusion, is that it helped us think about the way particles are created and destroyed. Because when an electron is flying through the universe, it doesn't just sit around happily. It generates photons, and those photons turn

into electrons and positrons would turn back into photons. Every electron is actually surrounded by like a fuzzball of virtual particles, photons and electrons and things popping in out of the vacuum. What do you mean? Like an electron is not always an electron. It's constantly kind of fuzzy and morphing and changing. Yes, exactly. It's constantly morphing and changing.

And it's surrounded by a ball of almost an infinite number of low energy particles that are being created and destroyed around it. And so we came up with this alternative mathematical formulation, quantum field theory, because it's really hard to follow the path of an individual particle through this sort of probabilistic storm of things that's happening. And it's much easier to just think about the field that's generating all these particles. And then a particle creation and destruction is much more natural in quantum field theory than an old quantum mechanics where you try to follow an individual particle as if it was a baseball.

So we had to sort of let go of this whole idea of particles having identities, particles having path, and just think of them as momentary oscillations in this field. Well, I think there's several questions here. Like, you know, maybe Yugi was also thinking of the wave analogy, maybe. And so maybe his question was, you know, just like you can follow a wave in the ocean. You know, if I make a ripple in a lake or something or a wave is made out into the ocean, you can kind of follow that wave, right? Like, that's wave A.

I'm going to call it Sally. And you can follow Sally as it moves across the Pacific, right? You sort of can. But what if Sally looks exactly like all the other waves? And there's billions of them. And you look away and then you look back. And you wonder, which of those waves is Sally? Hmm.

That's sort of the situation where you. The one that, like, if I see it at point A and I see at point B one second later, Well, that's his question, right? It's the one that's a point C another second later, basically, right? Could be, or could be that along the way got turned into something else and then got turned back into a wave,

and is it the same wave then? But it almost always is, isn't it? Like, do electrons really just transform to something else? Constantly. We're not looking? Constantly. Even while we're looking,

electrons are constantly in flux. Yes, exactly. You know, there's that... Even the ones like in my body. Even the ones in your body are not special. sorry to inform you. You know, there's that ancient philosophical question, right?

There's some ancient Greek ship. And every time it comes into harbor, it's lost a piece and they repair it. And then after five years, there are no pieces of the original ship. And they wonder, like, is it still that same ship? You know, if it's made out of all new pieces? And it's sort of that question. But it's the particle version of that question. Wait, what if it rides the same wave, though?

That just blows the Greek's mind. Yeah, exactly. And so I'd say in the same way, there is really no particle identity. I don't know that I've smoked enough banana peels to say they're all the same electron. But I think sort of what he's saying is that they're all manifestations of the same field. There's really just one electron field, and it appears in lots of different places in the universe. But then what's really going on? Because, you know, I feel pretty consistent, you know, like I am this way sort of now and I'm sort of the same way a second ago.

I think that's my perception. Are you saying that, you know, I could have changed something totally different between now and the next second that I am conscious about? Yes, but the Horaness is not about the stuff that you're made up of, but the arrangement of those particles, right? just like that ship is not about the pieces of wood that went into it, but how they're put together and what it's doing and how it spends its time. And so in the same way, you were a constantly frothing mass of quantum mechanical particles, but that's not what makes you, you. What makes you use the way they're arranged and the way they live their life.

Well, I am a constant frothing mass of something, for sure. It's a really hard question. And, you know, this is a question which is definitely on the philosophy side of the threshold. And something I love about physics is that it bumps up against philosophy so often because there are deep consequences to the answers of physics questions. And so I've always been really interested in the philosophical implications of particle physics. But I have to say, it's not something that most of us, most of us particle physicists are actually qualified to talk about, even though we do pontificate long-windedly on it. Oh, I see. It's one of these questions that the answer is

kind of like, it depends on what the definition of is, is, kind of. Unfortunately, I have to go there. But I think it applies in this case. Yeah. Right? It's sort of like it depends on what you mean by having an identity or being the same electron. Exactly. You can dig into that forever and smoke banana peels and not necessarily make any progress.

Exactly. Yeah, or cigars. Or cigars. But it's a really fun question. So thank you for asking it. Yeah. Well, what would say the answer then? Do electrons have an identity?

Or can you have the same electron? The answer seems to be... I would say no. I would say identity is a macroscopic quality that we like to attribute to things because we're used to it, because we're familiar with it. We expect also tiny particles to have it,

but they don't. And so I think it's odd. And it tells us more about how we think than about how the universe works. So you're saying at the microscopic level, at the individual electron level, these things we can apply because things are just constantly changing and frothing and... Yeah, exactly. I don't think it has any meaning at the microscopic level.

All right. Well, thank you, hear you from the Netherlands for that question. Please keep listening. I hope we answered your question. We can answer your question to your satisfaction. So we have one more question, and this one comes from Mexico or Mexico, about dark banner stars. But first, let's take a quick break. December 29th, 1975, LaGuardia Airport.

The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal. Apparently, the explosion actually emboating. Held metal, glass. The injured were being loaded into ambulances, just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, and it was here to stay.

Terrorism. Law and Order Criminal Justice System is back. In season two, we're turning our focus to a threat that hides in plain sight. That's harder to predict and even harder to stop. Listen to the new season of Law and Order Criminal Justice. system on the iHeart radio app, Apple Podcasts, or wherever you get your podcasts. I don't write songs. God write songs. I take dictation. I didn't even know you've been a pastor for over 10 years. I think culture is any space that you live in that develops you. On a recent

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From Mary Mary to Jennifer Hudson, we get into the soul of the music and the purpose that drives it. Listen to Culture raises us on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts. Imagine that you're on an airplane and all of a sudden you hear this. Attention passengers. The pilot is having an emergency and we need someone, anyone, to land this plane. Think you could do it? It turns out that nearly 50% of men think that they could land the plane with the help of air traffic control. And they're saying like, okay, pull this, do this, pull that, turn this. It's just, I can do it in my eyes closed. I'm Mani.

I'm Noah. This is Devin. And on our new show, No Such Thing, we get to the bottom of questions like these. Join us as we talk to the leading expert on overconfidence. Those who lack expertise lack the expertise they need to recognize that they lack expertise. And then, as we try the whole thing out for real. Wait, what? Oh, that's the run right.

I'm looking at this thing. Listen to No Such Thing on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. All right, our last question of today comes from Ben, who is sending his question from Mexico, and he has a question about dark matter stars. Hi, Daniel, I'm Jorge. This is Benjamin from Mexico. And I was wondering if the dark matter has all this gravitational properties as the

regular matter, why haven't astrophysicist discovered yet a big celestial body made of dark matter, like a dark matter star or something big that we can indirectly know it's there? Thank you. All right, that's a pretty cool question. Why aren't there dark stars besides a in comic books? I think that's the theme of a comic book villain. If not it should be. Yeah, exactly. No, it's an awesome question and the way I interpret it is that he's wondering why can't we tell that dark matter is there why hasn't dark matter coalesced into some sort of object that we could then pinpoint because I think he maybe is frustrated at the sort of diffusiveness of dark matter we know it's there we know it's sort of everywhere but we can't seem to say exactly where it is and why not is that how

you interpret the question why does it stay so fuzzy yeah yeah exactly right and I think that the key thing that understand here is remember that gravity is really, really weak. And it's the only way we can see dark matter so far. The only way we can feel it is through its gravity. And so it takes a huge amount of stuff to notice something just from gravity. Remember that gravity is so weak that you can feel the earth's gravity, but you can't feel the gravity of your car or your house, even though there is a gravitational pull there. It takes some huge body to even feel it, right? Well, maybe we should recap in a little bit about dark matter. right? So we know that dark matter feels gravity, right? That's how we sort of know it's there

because it's pulling us around the galaxy, but it doesn't feel electromagnetic forces, which means we can't see it or touch it, right? That's right, exactly. It doesn't give off light, it doesn't reflect light. We can't see it using any of those normal methods that we usually use to see stuff. Right, but it does feel gravity. And so I think maybe Ben's question is, If dark matter feels gravity, why hasn't it clumped together out in space because it's attracted to itself, right? Isn't it attracted to itself? Dark matter is attracted to itself by gravity. Absolutely. Yes. And it has clumped together, right? Dark matter is not evenly spread throughout the universe. Dark matter has clumped together thanks to gravity

and it's formed these big blobs. And it's, in fact, only because dark matter has clumped together to make these blobs that we have galaxies and we are alive because without dark matter's gravitational pull there wouldn't be enough gravity to hold galaxies together and we've done simulations and seen that in universes without dark matter it takes a lot longer for gravity to pull all this luminous stuff together to make stars and planets and galaxies so dark matter does make structure it does make objects but those objects are sort of big and diffuse and And they're sort of the size of the galaxy. And you might ask, well, how do we know that the dark matter inside the galaxy

hasn't also clumped together to make, you know, star-sized stuff or planet-sized stuff the way normal matter has, right? And we don't know the answer to that, right? And the reason we don't know is because we can't see dark matter in enough detail. Like, it's totally possible that the distribution of dark matter in the galaxy is either A, totally smoothly spread out, right? B, sort of, you know...

Like a cloud. Like a cloud. Now, we know it's denser towards the center and less dense towards the outside, but it could still be like a big cloud, right? Or it could be that their structure that it's clumped together to make a bunch of dense points

just the way normal matter has. So there could be dark matter stars. Yes. Or dark matter planets. Exactly. But the only way to see them would be through gravity. And it's really hard to see the gravity from like one planet or the gravity from one star,

right, unless it's really close by. Like if there were dark matter stars and a dark matter star passed near our solar system, then we could detect it, the way we detect black holes, right? Black holes are invisible. We detect them from their gravity. Sometimes we detect black holes because of the x-rays that are produced from compressed gas nearby, but a lot of black holes we see through their gravity. But you need to be a pretty big black hole to detect its gravity from far away or to see its gravitational effect on nearby stuff, right?

And in fact, there are a few of these things that we found, and they have a pretty silly name. You ready for it? Always. Physics silly names? Yeah. No, they're called. That's what I live for. Back a long time ago, before we knew whether dark matter was a thing, people were wondering if there were just big clumps of normal matter that was sort of hidden out there.

And they gave them this name, massive, compact halo objects. And the acronym for that is M-A-C-H-O, right? So, machos, not nachos. Not nachos are a totally different thing. These are machos. Right. And so... That's not physicists overcompensating for anything at all.

Not at all. No, and so people went out there and looking for these things, like can we find dark blobs out there, dark condensed blobs out there that might be responsible for all the missing mass, right? And they did find a bunch of them, not nearly enough to account for all the dark matter, but they found a bunch of them. They would find them like eclipsing stars or bending the path of other objects. And so we know that there are dark objects out there.

Some of them could be dark matter, right? Some of them could be. So it's totally possible that dark matter has clumped these objects together. We just don't have the gravitational sensitivity to see them because they're too small, essentially, and gravity is so weak. Like our ability to notice or feel or see dark matter

is not at the planet or at the star level. It's only at sort of the galaxy level. Yeah, exactly. A little bit less than the galaxy. We can get some sense of where they are based on how rotations vary as a function of the radius from the center of the galaxy, but roughly, yeah,

much more at the galaxy level than the star level. But it's fun to think about. Imagine what would happen. What would happen if you had a huge blob of dark matter and it coalesced into sort of a tight blob? Like, would it make a star? Like a planet. You know, when we say a star, we sort of mean something that's big enough, has enough gravity that has pushed the stuff together that begins to fuse and release energy, right?

And so another interesting question is that what would happen if you squeeze that much dark matter together? Would interesting things happen, like, you know, elements fusing and releasing photons and things like that? Well, we don't know, but we know it's not made of elements, right? It's not made of atoms. It's made of some other kind of matter. And the only interaction we know it has is gravity. So as far as we know, it would just squeeze and squeeze and squeeze and squeeze, and squeeze, and there's no repulsion, right? The thing that keeps a star or a planet from immediately becoming a black hole are the other forces it feels, like electromagnetism, which, and the strong force, which fuel fusion, right, which keeps a star exploding.

It keeps it from collapsing immediately. So if dark matter has no other forces, then every time it gets to be a pretty dense clump, it's just going to turn into a dark matter black hole because it's just gravity. But if dark matter does feel some other force, maybe some new force we've never seen before, that only affects dark matter on dark matter interactions, then maybe clumping a bunch of the dark matter together

could spark some sort of dark matter interaction, which could release like dark photons. We're just wildly speculating here because we just really don't know what happens when dark matter bumps into dark matter. Dark photons and dark light. Yes, exactly. It sounds like all good comic book characters.

That's right. Today we've been exploring the connection between physics philosophy and physics and comics books. It's trifecta. I think, you know, maybe that's where Ben's question came from. You know, like, you know, we know dark matter feels gravity. So why hasn't it clumped into dark matter black holes? You know, why is it still kind of diffused and not more noticeable, you know? Right. Does that mean that, you know, these alternatives you mentioned are maybe probably true, you know, that there are other forces or there are maybe other mechanisms going on inside of a dark matter?

Absolutely. I think a lot of physicists believe that there must be some other kind of force that dark matter feels, not just gravity. And the sort of complicated arguments for that based on what happened in the early universe and how some matter and dark matter turned back and forth into itself, we have indirect evidence of that happening. which suggests there must be some other force that dark matter feels, but we haven't figured that out yet at all. It's really, it's very indirect arguments. But there is one thing that keeps dark matter from collapsing quickly into a black hole, and that's our old friend rotation.

One thing that keeps the galaxy from collapsing into a black hole is that it's spinning. And so that keeps the stars from falling in. Just the way the earth spinning around the sun keeps it from falling into the sun, right? It's an orbit. If you have a huge blob of dark matter and it's rotating, that rotation keeps it from collapsing gravitationally into a black hole. And so that's something that dark matter can do, even if it has no other interactions.

But yeah, I think that it's totally possible that dark matter has formed really dense blobs inside our galaxy and it's possible that there's new interactions doing weird stuff inside those dark matter objects that we have no idea about. But I think what you're saying maybe is that we sort of have inside. seen that yet, right? Like if we are surrounded by dark matter stars or dark matter, you know, giant asteroids, you know, and one of them came through our solar system, we would notice it, right? Like we would notice all the other planets going, whoa, gravitation. Yes, exactly. That's the kind of thing we would notice for sure. I mean, we noticed Omuamua, right? This tiny little rock coming

through from deep space and passing through our solar system with no gravitational interaction at all. But it was reflective. But imagine some really dense, heavy object that perturbed the path of the planets, that we would definitely notice, yeah. It would have to be pretty big, though, because gravity is pretty weak. So, like, some random rock flying through the universe, we wouldn't notice. It'd have to be, you know, like, it had to be a pretty significant object. I'm not sure exactly how massive, but some significant fraction of the mass of the sun at the very least. Yeah, we would notice it, right? It would totally disrupt our solar system. Yeah, absolutely.

But there could be a lot of these dark matter blobs out there, and just none of them have passed through the solar system because the galaxy is huge, right? And there's lots of blobs out there that are made of normal matter that don't pass through our solar system. It doesn't mean they're not out there. I mean, there could be a giant banana-shaped mass of dark matter out there. Just waiting for us to slip on.

That's right. You're going to tie all the questions together. What if there's a banana-shaped mass of dark matter, creating a solar system-sized black hole, and we're in it. Could we tell if there was another one that was identical? All right. Well, I guess that's Ben's answer is that there could be dark matter stars and planets or things out there.

We just can't see them yet. That's right. We just don't have the right glasses to see it more sharply, right? That's right, yep. And it's not clear that we ever will because we don't know what glasses to put on or if there are glasses that you can. could even potentially theoretically put on to see this stuff. Well, obviously, we just need dark glasses.

I wear my sunglasses at night. I don't know about you. All right. Well, once again, thank you listeners for sending you as your questions. We love to interact with you online. And so please follow us and please tell your friends about this podcast. That's right. And if you're listening to us talk about something in physics and you have a question that pops into your mind, please share it with us. The reason we're doing this podcast is to clarify these things and explain them to you. And so if there's something we've missed, we want to get on it.

Yeah, and we'll answer it even if you are not our sons. Unless you're on Instagram. In that case, sorry. In that case, you're out of luck. Do you have any sons on Instagram you're not aware of? If you're trendy and like the rest of the universe, then maybe you should ask the question on Twitter. That's solid advice.

All right, thanks for listening. Hope you enjoyed it. Thanks for tuning in. If you still have a question after listening to all these explanations, please drop us a line we'd love to hear from you. You can find us at Facebook, Twitter, and Instagram at Daniel and Jorge, that's one word, or email us at Feedback at Danielandhorpe.com. Thanks for listening, and remember that Daniel and Jorge Explain the Universe is a production of iHeartRadio.

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