Daniel and Kelly’s Extraordinary Universe - What's the most promising theory of EVERYTHING?

Episode Date: May 11, 2021

Daniel and Jorge talk about string theory, loop quantum gravity, M-theory, p-branes, geometric unity and ice cream! Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

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Hey, Daniel, what's the one thing you most want to understand about the universe? Hmm, I think I might say everything. Does everything count as one thing? Well, it does if we understand all of it together and how it's all like connected. You mean like how we're all one with the universe, man? Exactly. Pass the banana peals, man. That's the goal. So when you go to an ice cream store and they say, pick one scoop of ice cream, do you try to order everything also?

Yeah, I do. I try to convince them of my unifying theory of ice cream. You know that unifying your veins, too, right? I do my best to bring it all together. Well, at least it's insightful and delicious. Hi, I'm Jorge. I'm a cartoonist and the creator of PhD comics. Hi, I'm Daniel. I'm a particle physicist and I eat a lot less ice cream than I thought I would when I was a kid. What do you mean? You had a projection as a kid and you're not meeting the expectations. No, when you're a kid and you think, wow, when I grow up and I get to decide what I eat, I'm just going to eat ice cream all day.

But turns out that's not really what I want. Really? What happened? You change your mind? You haven't found your perfect ice cream flavor yet? Maybe I just ate too much ice cream in college and then I'm just done. Oh, so you did accomplish your goal. It's just that, you know, you found out that once you achieve your goals, then, you know, life goes on. Yeah, maybe I blew through that one a little too quick and I got to move on to something else. Or maybe it's the opposite. Life stops going on if you eat too much ice cream and you realize that.

Maybe that's it. Maybe life should be measured in scoops of ice cream. Maybe everybody lives the same number of scoops of ice cream. And you blew it all in your 20s. But welcome to our podcast, Daniel and Jorge Explain the Universe, a production of IHeart Radio. In which we try to take a big scoop out of the universe. We serve you up a delicious ball of sweet, sweet understanding of the mysteries of the universe. We talk about everything that's out there in space, the crazy stuff colliding and producing gold, the weird stuff in tiny little particles.

We think about where it all came from, where it's all going, and what it's all going to do. And we try to make sure all of it makes sense to you with a cherry on top. And some sprinkles. Because even ice cream is made out of physics, right? Ice cream is made out of particles, which are made out of sub-particles, which are made out of sub-sub-particles, which are made out of the same particles that everything else in the universe is made out of. Stars, planets, moons, asteroids. It's all sort of one big, continuous, giant, delicious, mostly frozen universe. With sprinkles on top, absolutely.

It's amazing, yes, but this picture that we can take the universe and, like, reduce it to tiny particles, so far seems to work, all the crazy stuff that's out there. It seems so different, but we can explain most of it by boiling it down to a few little bits and how those bits fit together. And, you know, I don't know why we live in a universe like that. It could have been that we lived in a different kind of universe, one where every kind of thing has its own particle and you don't really get any simplification when you try to take it down to the lower level.

But fortunately, we do live in a sort of Lego universe where there are a few basic building blocks and everything comes out of the arrangements of those. Yeah, it is pretty odd to think about, right? Like, even frogs are made of the same thing as, you know, quasars and giant asteroids floating in space. It's all sort of made out of the same little bits and pieces. Yeah, and it's not just like the same types of bits. It's actually the same bits in a basically the same proportions.

You have the same ratio of protons, neutrons, and electrons in basically every element. And every element, it makes everything. And that means that basically everything you've ever eaten is just a different arrangement of the same number of protons, neutrons, and electrons. Yeah. And it seems like there aren't that many of those particles, right? Like as far as we know, the standard theory of physics says that right now we think there are about only, what is it, 12 particles in the entire universe? Well, it sort of depends on how you ask, right? Like most of the stuff we see out there in the universe is made out of only three of them, of quarks, down quarks, which give you protons and neutrons.

and then electrons. You only need those three to make most of the stuff. But then we have found other particles. And you're right, we're up to 12 now matter particles. But we don't know if those 12 particles are actually fundamental, if they're made of something smaller, or if there are more particles out there. There could be like 12 million particles.

We just haven't found most of them yet. I guess it's kind of like how we, you know, discovered the periodic table of the elements at some point. And we thought we had everything figured out. And then it turned out that each of those elements, is actually like a copy or a repeat of the same sort of smaller particles, electrons, protons, and neutrons. And even those turned out to be made out of other particles. And another flabbergasting and amazing fact of the philosophy of science is that we seem to be able to understand the universe

differently, but effectively at all of these different levels. Like chemistry kind of makes sense, right? You don't need to know all the details of the particles for that to work. And then you drill down into the atomic physics and that kind of makes sense. And nuclear physics makes sense. And nuclear physics makes sense. And then you get down to like the tiny, tiny particle physics. And there's all these sort of layers at which you can think about the universe made of pieces. And the rules of those pieces are understandable. But we can also drill down and find even smaller pieces. So it's incredible to me that there are these layers of understanding.

You don't have to go all the way to the tiniest bits in order to make sense of the universe around you. I just like how you use the word flabbergasting. I am flabbergasted. Golly, gee. I am grateful and amazed that. the universe is sensible. You know, sometimes listeners write to me and they ask, like, do you think it's possible for us to understand the universe,

that one day far in the future, humans will understand everything? And, you know, I don't know the answer to that. Obviously, we can't know. But, you know, I don't think dogs will understand the universe. We're a little smarter than dogs, but I don't think we're maximally smart. So there's certainly a chance that we won't. So I'm just kind of grateful and flabbergasted that we figured anything out.

Right. I think maybe dogs. understand the universe to the extent that it serves them, you know? Like, most dogs probably feel like they have a pretty good sense of the universe around them and are comfortable. Maybe that's our future, you know. We'll just understand it as far as getting our treats and our rubs in the tummy go and then maybe we'll stop.

Well, I think dogs would definitely be better off if they were smarter. Like, my dog thinks that every time the refrigerator opens, it's getting a treat. But that's definitely not true. And if it understood, like, you know, how to open the fridge on its own. or what time of day it typically gets a treat or what it should do to encourage us to give it a treat, I think it would get more treats and waste less time. Yeah, but then you just eat ice cream all day, Daniel.

Maybe dogs are smarter than you think. I'm pretty sure a dog would eat ice cream all day if it had the chance. Let's do that experiment. Let's put some ice cream in front of a dog and see what happens. Maybe the key to happiness, Daniel, is not getting what you want to be optimistic about getting what you want. Maybe dogs are one with the universe more than we are. Well, maybe this is turning into a dog psychology podcast.

Welcome to the dog whispering philosophizing. Daniel and Jorge explain your pets to you. Oh my God, that is a winning podcast idea. Let's pivot here, Daniel. Your cat is really just not that into you. And now tell me about your rats. Do they get flabbergasted as well? Our rats have unfortunately passed away because rats only live a couple of years.

They're wonderful pets. They're smart. They're intelligent. They're responsive. They're actually affectionate. but they are sort of short-lived. It was a bit sad. That's why we now have a dog.

I'm sorry. I guess they went back to being particles. They live on. Their particles live on through the universe. It seems like it's all connected. Everything's made out of the same basic particles, which I think makes physicists wonder if you can go further and break things down even more

and maybe get down to one particle or one type of particle that ties the entire universe together into one theory. We would love to do that to explain everything, in terms of one equation, we could just write on a t-shirt. Hopefully not a big t-shirt. On a one-z. Or maybe like one with extra long coat tails.

That'd be a new fashion statement. Or in super duper tiny font that you need reading glasses to read. No, we want a simple theory. We want to reveal the fundamental nature of the universe. A goal of physics is not just to optimize our ice cream intake, but to sort of understand to have that moment where we like, we get it. We're like, oh, that's how the universe works. And to do that, we want one simple idea that tells us what the rules are.

Yeah, it's a big goal in physics. It's the ultimate dream, perhaps, of a physicist to discover it. And so today on the podcast, we'll be asking the question. What's the most promising theory of everything? Everything. Everything, like everything, right? Like all of it, yeah. I guess you could also call it the most promising theory of the universe.

Yeah, except that these days we've gone beyond the universe. We have the multiverse. And so, you know, maybe you should call it the every verse or the all-a-verse or something. The everything's. The most promising theory of everythings. You can't have everythings. That could be the sequel to the theory of everything, the movie. The theory of everything.

The theory of the theory of everything. Yeah. So it's a goal in physics to come up with one, I guess one equation, Daniel. What do you think this theory will look like? One equation, one table. one, you know, fortune cookie piece of paper, what will this theory look like? What will this theory look like? Wow, I wish I knew. You know, currently we use math as the way we express our ideas.

Matter and forces are both described by fields, which are expressed as quantum field theories. And so one hope is that we could generalize quantum field theory and use it to describe things at the smallest level. But, you know, we've explored a tiny little fraction of the universe. as you say the universe is mostly cold and things are moving slowly and it could be that what we've learned is not representative and it's always dangerous to extrapolate from like a tiny little corner of the universe to the rest of it you wouldn't say you understand elephants if you've only ever looked at one elephant's tail for example and so i'd love if quantum field theory was the path forward but i suspect we need some sort of completely new kind of mathematics in order to make progress towards this final theory Oh, man. You have to discover new math before you can discover a new physics. Absolutely. We're constantly inventing or discovering new math to make progress. It's this fantastic sort of duet between math and physics.

Mathematicians invent some new tool. They're like, hey, this is useless but fun. And the physicists are like, wait, I can use that for something. Bring that over here. I'm going to build that into my theory. And I'm never actually sure whether mathematicians are like delighted to have their tools find use or a little disappointed that they've been like sullied by brought into the physical world. Do you think they see you as a duet partner or as like a backup singer? Oh, I definitely think that mathematicians think of physicists as sort of like unnecessary frosting on the cake. You know, I think mathematicians see themselves as more primary and fundamental than physicists. The way I think a lot of physicists think about chemistry and biology, you know, sort of these like layers of the onion.

I heard one mathematician describe his department as the halls of truth without irony. The halls of snobbery, which I can't. trickles down is what you're saying. There's a trickle down effect for snobbery in the sciences. There's a whole hierarchy of snobbery, absolutely. Meanwhile, everyone uses their phones and computers, which are made by engineers to do their science. Exactly. And it's not just limited to science. The snobbery is everywhere. But anyways, this is a big question, a lofty goal. And we were wondering, as usual, if people out there on the internet had ideas about everything, which sounds like a redundant question. As usual, Daniel went out there and

ask people if they knew what the most promising theory of everything is. And so thank you to everybody who volunteered, and especially to our recurring superstar Lucian, who has volunteered, I think, consecutively for every single one of the last 40 episodes. If you'd like to participate, please don't be shy. Write to me to Questions at Danielanhorpe.com. Think about it for a second. What do you think is the most promising theory of everything? Here's what Lucian and a lot of other people had to say.

Um, I don't know much about candidate theories or of everything. The only one I know a bit about is the string theories. As the one. I think is maybe string theory, which I've also heard referred to as brain theory. Has it evolved a little bit instead of just strings. Now they're saying maybe it's membranes. I didn't know there was more than one theory of everything. That's pretty cool.

Something to do with the theory that unifies general relativity and quantum theory, maybe? It makes me think of social media. If you go there, you'll have people having theories about everything. But the most promising one, it's the super string theory, I guess. the ones that Brian Green and others are working on it. I'd say the most promising theory of everything is the Big Bang theory. It encompasses all of the sciences and ties them together neatly into a theory for cosmology and especially for chemistry, physics, all of it.

It just seems to go together well. I like string theory, but I'd say the Big Bang theory is better. Dr. Michio Kaku speaks of an elusive, elegant equation, perhaps an inch or so long that operates in both the quantum and relativistic realms. I would have to side with Professor Kaku and nominate string theory as the most promising, but I think that squeezing all that math down to an inch will be a bit of a stretch. I will vote for string theory. Well, I happen to think loop quantum gravity is on the right track,

but that's not actually a theory of everything. String theory seems to be losing favor, as I think is also M theory. The many world's explanation of things is always right because there's always a place where it's right. But I don't really know the answer. I think the most promising theory of everything is the M theory that can only be done

by that one guy whose name I can't remember and nobody else seems to understand it. All right. I think I just realized something, Daniel. What's that? The acronym for a theory of everything is T-O-E, T-O-E, toe. So really you're looking for the big toe of the universe. Yeah, that's sort of tough to reconcile with the snobbery of particle physics, isn't it? What do you mean?

Are you saying toes are ignoble somehow or not worthy of the highest regard? Definitely, exactly. Toes make me think of, you know, toe cheese is kind of smelly. You can stub your toe. You know, toe is not like poetry written about people's toes very often. Haven't there been love songs devoted to toes? Sing me one. Aren't some people into toes?

I'm into theories of everything, so maybe put me in that category of being into toes. I see your toe theory fetishist. But our listeners have definitely thought about the theory of everything. There were some good answers here. A lot of people mention string theory. I feel like people are maybe familiar with that idea that maybe it could be a theory of everything. Yeah, and thank you to all those listeners. and I want to make a shout out to one of our youngest listeners,

two and a half year old Hannah from Australia. Her dad wrote to me and said that she was home from child care, was sick and she asked him, can we listen to Daniel and Jorge? So thanks Hannah for listening to our podcast. And you said obviously the answer is no, right? I'm not her dad. We're not qualified to take care of children, Daniel,

especially not other people's children. I think Hannah should get some more ice cream. What do you think, Jorge? I think she should maybe be listening to some math podcast instead. But, you know, I say a lot of ideas out there about a theory of everything. So let's break it down for people. And so real quick, Daniel, what would you say is theory of everything? How would you define it?

Well, everything for physicists means like all the experiments. We want to explain basically anything that you can do. We want to be able to predict what happens. We don't want any surprises. We want to be able to say, if you smash these two particles together, here's what's going to happen. If you drop a feather on the moon, here's what's going to happen. If you bring all this matter together, here's how a black hole forms. We want to be able to predict what happens.

We want to know what the rules are. And so at the most fundamental level, that means explaining all the kinds of bits of stuff there are out there, all the matter, and then all the rules about how those bits talk to each other. So like all the forces. So put simply, we want a single description, a single idea, a single mathematical equation that explains all the matter and all the forces in the universe. Like one theory, one framework or one equation that can tell you what's going to happen.

Or maybe not what's going to happen, but what's likely to happen, right? Yeah, exactly. Our universe is quantum mechanical, which means we can't say exactly what will happen, but it's still deterministic because we can say what's likely to happen. We can say, if you shoot an electron at a proton at this angle, here's exactly the distribution of possible outcomes. And so the wave function is still deterministic, even if how it collapses is not. Right.

Or more accurately, like, if I smash these two particles together, a hundred million times that you should get, you know, approximately X proportion of this happening or X proportion of that happening. Yeah, if you're a frequentist and that's how you interpret probability, then yeah, exactly. In a hundred million similar experiments, you would get this distribution of outcome. If you're a Bayesian, then you say, well, there's a probability of various outcomes. Did you just call me a frequentist? Yeah, you just outed yourself as a frequentist. I don't know whether I should be offended or flattered. I guess it depends on your posterior.

I guess I feel flattered, you know, 50% of the time. Offended another 50% of the time. No, don't. I'm a frequentist. I think it makes a lot more sense. All right. Well, let's get into some of the details about what a theory of everything would apply to and what are some of the leading candidates right now.

But first, let's take a quick break. 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, 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. My boyfriend's professor is way too friendly, and now I'm seriously suspicious. Oh, wait a minute, Sam.

Maybe her boyfriend's just looking for extra credit. Well, Dakota, it's back to school week on the OK Storytime podcast, so we'll find out soon. This person writes, my boyfriend has been hanging out with his young professor a lot. He doesn't think it's a problem, but I don't trust her. Now, he's insisting we get to know each other, but I just want her gone. Now, hold up. Isn't that against school policy? That sounds totally inappropriate.

Well, according to this person, this is her boyfriend's former professor, and they're the same age. It's even more likely that they're cheating. He insists there's nothing between them. I mean, do you believe him? Well, he's certainly trying to get this person to believe him because he now wants them both to meet. So, do we find out if this person's boyfriend really cheated with his professor or not? To hear the explosive finale, listen to the OK Storytime podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. I'm Dr. Joy Harden Bradford, and in session 421 of therapy for black girls,

I sit down with Dr. Afea and Billy Shaka to explore how our hair connects to our identity, mental health, and the ways we heal. Because I think hair is a complex language system, right, in terms of it can tell how old you are, your marital status, where you're from, you're a spiritual belief. But I think with social media, there's like a hyperfixation and observation of our hair, right? That this is sometimes the first thing someone sees when we make a post or a reel is how our hair is styled. We talk about the important role hairstylists play in our community, the pressure to always look put together, and how breaking up with perfection

can actually free us. Plus, if you're someone who gets anxious about flying, don't miss session 418 with Dr. Angela Neil Barnett, where we dive into managing flight anxiety. Listen to therapy for black girls on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. Get fired up, y'all.

Season two of Good Game with Sarah Spain is underway. We just welcomed one of my favorite people and an incomparable soccer icon, Megan Rapino, to the show, and we had a blast. We talked about her recent 40th birthday celebrations, co-hosting a podcast with her fiance Sue Bird, watching former teammates retire and more. Never a dull moment with Pino. Take a listen. What do you miss the most about being a pro athlete? The final. The final. And the locker room. I really, really, like, you just, you can't replicate, Kate, you can't get back, showing up to locker room every morning just to shit talk. We've got more incredible guests like the legendary Candace Parker and college superstar AZ Fudd.

I mean, seriously, y'all. The guest list is absolutely stacked for season two. And, you know, we're always going to keep you up to speed on all the news and happenings around the women's sports world as well. So make sure you listen to Good Game with Sarah Spain on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Presented by Capital One, founding partner of IHeart Women's Sports. All right, we're talking about the big toe of the universe, the big theory of everything that could maybe one day explain everything that happens and predict exactly how it's all going to turn out,

every little nook and corner of the universe. Right, Daniel, that's what a theory of everything promises. That's what a theory of everything promises. promises yeah it's to explain everything in terms of one idea and you know the history of physics is that we saw a lot of weird stuff and we try to explain sort of each bit and then we looked for patterns and we try to like organize the stuff into groups we said well you know what maybe lightning and static electricity are actually the same thing then we developed like a coherent explanation for electricity and so the basic step forward there is not to say lightning is static electric

obviously they're related but they're different you try to fit them together into a common idea right to say these two things are part of the same larger concept they both come from the same effect or the same i don't know equality in the universe or something yeah and you can generalize that a little bit like we've made further progress by noticing that there's a deep relationship between electricity and magnetism right that like particles that have charges on them for example are affected by magnets and particles that move can make magnets. So there's this deep connection between electricity and magnetism and we unify that into electromagnetism. Again, that doesn't say, oh, electric charges are the same as magnets. It's not saying that they're identical.

It's just saying that it makes more sense to fit them together. They're two sides of the same coin and mathematically they sort of click together like pieces of a puzzle. Like they can be predicted by the same equation. Yeah, there's a symmetry in the equations, in fact. If you look at the equations of electromagnetism,

you notice that the electric field and the magnetic field have exactly the same and opposite rules. So there's four of those equations. And if you swap the electric field, the magnetic field, in all of them, you get the same equations. So that's kind of cool. I guess, you know, there's a lot to the universe. There's a lot in the word everything.

And so would this cover everything? Like matter, forces, space, time. Are you trying to wrap that all up into one equation? Yes, exactly. I want all of it. You know, put all those scoops under one big cone. we definitely want to explain matter like we were talking about before we would love to understand what is the most basic element to the universe first of all how many basic elements are there in the

universe and by elements i don't mean you know like lead or iron i mean the most fundamental thing in the universe the basic ingredient the smallest piece out of which everything is made we'd love to understand what that is you know we don't think that the current list of particles we have are fundamental. We don't think that those are the answer. Right. They might be reducible to simpler bits and pieces. Exactly. Because when we look at these particles, we notice weird patterns. Patterns that don't make any sense. Patterns that don't have any explanations. And those patterns are typically, historically, very valuable clues that lead you to figuring out how to sort of assemble the current list of

fundamental particles out of something smaller to figure out how they might be made out of different combinations of smaller bits. And it would also have to cover the forces, right? Or do you count those as particles? Because forces have particles too, right? Yeah, we would love to explain the forces. And we can explain the forces in terms of fields and then ripples in those fields

and being interpreted as particles, absolutely. So you can think about the universe as made of fields or made of particles either way. So forces you can think about as fields or as particles. But we definitely like to unify these forces and to understand them together. What we were talking about a minute ago was sort of the unification of electricity and magnetism. And we've made a lot of progress there.

We've even unified electromagnetism with the weak nuclear force. This force that's responsible for beta decay, radioactive decay, and other sorts of radioactive processes. We understand them now to be like part of one larger mathematical construct, the electro-weak force. And we're sure that's correct. We know that that's true that it reveals something deep about the universe because realizing how those two things click together is what allowed us to predict the existence of the Higgs boson, which was a pretty big step in unifying everything. So would this include then also gravity as well? Do you hope to sort of explain gravity in one quantum framework? Yeah, absolutely. We would love to

explain all of the forces together. Now we have some forces for which we have a quantum mechanical description like electromagnicism and the weak force and the strong force. We haven't yet managed to merge all those quantum mechanical forces together. These are the forces that you can describe in terms of quantum field or particles passing back and forth. And we have not yet unified the strong force with those other ones. So that's left to be done. We would also like to understand like, is gravity even a force?

Does it belong on this list? Like you mentioned earlier, we want to unify all the stuff, all the forces, and then space and time. Well, are space and time really their own separate thing? Are they just manifestations of some quantum gravitational, quantum mechanical force? Are they really something different? We don't understand that at all. So yes, we would like one clear understanding where all the pieces fit together and all the pieces have to be there. Like it's a complete puzzle, not just a few pieces that stick together. Like you don't want to have

any bits left over where you're like, what is this for? Or how does this fit in? Oh, I don't know. Just keep it there on the side. No, you want like the equations to tell you why that thing is there or why it's not there. Exactly. And we want the math to lead us there. We want to find like symmetries that say this is the only way these equations work because they have to follow this rule. You know, like we have symmetries that say, for example, every inertial frame of reference follows the same law of physics. And that really limits the kinds of laws of physics that you can write. You can only write ones that follow those rules. And we think that that's a symmetry of the universe. And so we'd like to sort of find symmetries that tell us how to write the laws of physics

and it would be great if there was only one possibility. If we're like, you know what, this is the only one that sort of works. It hangs together. It has all the pieces we need. It doesn't have any extra bits that don't correspond to things we see. And so that would be really beautiful. And then we could look at that and say, okay, what does this tell us about the universe? What does this reveal about the source code of the universe? Speed out of vanilla. That's what it's trying to tell is Daniel, it's the writing on the sweeteners wall there. No, I would guess the universe is probably raspberry flavored. You know, there's these huge gas clouds of ethels in the center of the galaxy and you know is it responsible for the smell of raspberries.

Are you saying God has a favorite flavor or a scent? I'm saying the universe has a smell and it's not vanilla. And it doesn't melt like nothing. Smells like everything. Yeah, exactly. It smells like barbecue. All right. Well, this is a pretty lofty goal.

I guess what makes businesses think it's even possible? Like, why should the universe be reducible to a few simple equations or laws or rules? Why couldn't the universe just be kind of crazy and random? Yeah, I think simply the answer is hope. we hope that it's possible we would love for it to be possible and like many human projects it's just driven by hope not faith you know just hope we would love to have an explanation for the universe that is simple and complete we don't know why any explanation for the universe holds like why does science even work why can you do an experiment today and then tomorrow the same laws of physics

still work we don't even know why that's true right so we're you know on sort of shaky ground philosophically. But we've made a lot of progress, right? This hope has fueled us towards a ever deeper understanding of the nature of reality and an ever simpler description. Like, as we peel apart matter, we do find a smaller number of simpler objects that explain complexity at a higher level. You really only need about three particles to explain hurricanes and hamsters and llamas and all that stuff. So so far it seems to work, we've made pretty good progress. But then, Daniel, the problem is you also have to ask, is there a theory of hope? Can you explain hope with a theory?

And then your brain explodes. It's a theory of inception. And it's not just hope, right? We've made some good progress. And also, we have some good tips. Like, we look at some numbers and we look at some trends and things seem to be going the right direction. What do you mean? Well, for example, we would love to explain how all of the forces are really the same thing.

You know, not that they're exactly identical, but that they're like four parts the same thing, the way like the power rangers come together into one big ranger or whatever you call that. So we'd love to do that. And one obstacle to doing that is understanding why they're all such different strengths, like the weak force is pretty weak and the strong force is pretty strong and gravity is like crazy weak. It's hard to understand how you have these four bits and fit them together if they're all such different strengths. Well, it turns out, and we talked about this on the podcast one time that the strength of the forces depends on the energy of the experiment you use to probe them like the charge of the electron depends on how closely you look how far you

penetrate into this like cloud of virtual particles that surround the electron well all of the forces are like that it's called the running couplings the value that dictates how powerful a force is depends on energy the amazing thing is that as you go up in energy all these numbers are pointing together. It seems like they're common together to one common value. There are a lot of hints that maybe it is possible to unify everything together because things sort of leaned that way. Yeah, things are leaning that way. We think that if the universe was really hot and dense and there was a lot of energy, that all these forces would be similarly powerful. The way, for example, magnetism seems weaker than electricity, right? Well, it turns out that if you're going at the speed of light,

the two things have equal strength, which is why photons can, exist because they're just electricity and magnetism like sloshing back and forth in perfect balance. So at the speed of light, those two forces are the same. And we think that in the very early universe or in very hot, dense environments, the strong force, the weak force, electromagnetism, and maybe even gravity all have the same strength, which would help us fit them together into sort of like one big idea. All right. Interesting. Well, I guess maybe let's go into now what are some of the leading candidates for this theory of everything. I know that there are a couple of ideas out there. Some are fringe. Some are more mainstream. And a lot of people seem to know about. So what are

some of these leading candidates for the universe's toe? Well, there's definitely one that's far out ahead of everybody else in terms of like number of people who were investing their careers in it and believing like it might actually lead to a theory of everything. And that's definitely string theory. Yeah. That's the one with the best PR department too. It seems like a lot of of you had heard of the string theory. Exactly. A lot of people have written really beautiful popular science books on it. And there's lots of specials about it and people talk about it.

It's also sort of cool and it's easy to sort of visualize because it tells you that the universe is not made out of these weird tiny dots that are hard to get your mind around. But instead that it's made out of these little vibrating strings. And now these little strings are they like part of a field? Are they just like strings floating in space? Are they part of a giant like universe, you know, guitar or what are these strings? So they are quantum objects, right? So in that sense, you can think of this as a quantum field theory, right?

And these little strings, instead of saying like, you know, a little energy located in a point in a field, instead of imagine like a one-dimensional version of a particle instead of a zero-dimensional version, imagine a one-dimensional version of a particle that would be a line. And then this thing can vibrate. you can have different kinds of energy. And the cool thing is that if you look at these strings from really, really far away, they look like particles because you can't sort of like see how wide they are. But if you zoom in, you would discover that all the things we call different particles are just the same string vibrating different ways. Like it vibrates this way, you get an electron.

Vibrates that way, you get a graviton. So you're saying like all quantum particles, like a quark or an electron, if you zoom in enough at the core of it, instead of a point particle, you'll see like a little what vibrating though? And how can it be one dimensional if the electron and the quark are multi-dimensional? Well, in our current theory, right, electrons and quarks are zero dimensional. They're just point particles that have no length, no width, no height. And so that's kind of bonkers.

It doesn't make any sense. You know, how can you have mass with no volume? I would have infinite density and, you know, turn into a black hole and all that stuff. We dug into that whole thing in another podcast episode. So this just takes it and stretches it out and makes it. one dimensional says it has length, but no width and no height. And then it can vibrate because that string can move because the quantum field itself can oscillate.

Right. But is it vibrating in any particular dimension or direction or is it in like another dimension it's vibrating? Yeah. So the mathematics of string theory are complicated, but it turns out that they work best if space has more dimensions than just the three that we're familiar with, if it has like 11 dimensions. And these other extra spatial dimensions would be sort of very hard for us to see. They would be very, very small. So it's kind of difficult to visualize. But imagine like every

location in space, right, X, Y, and Z. Those are the three dimensions. Now at every location, you can also like go around or you can like turn or there's like another direction, another dimension of your location, another value you need to specify to say exactly where you are. Interesting. So it's reducing quantum theory to like little string theory. Yeah, exactly. And then these strings oscillate often in these other hidden dimensions. Now, there are some theories of extra dimensions of space and time in which those dimensions are very simple. They're just like little loops. And those are fun. We've talked about them on the podcast. String theory requires these extra dimensions to be really complicated objects.

They're called Kalabi Yao Manifolds. They want a very, very complicated geometry. And anyway, the strings would like vibrate in these crazy dimensions. That would be invisible to us. But based on their vibration in those dimensions, they would appear different to us. So if it vibrates, you know, this way and all those other dimensions, then it would be an electron. It vibrates that way it would be a muon. And that would be pretty awesome to understand like, oh, electrons and muons, they look like one is a copy of the other one. That's because one is like the resonance of the other one.

Or it's, you know, a different standing wave of this vibrating string in this other dimension. It would help us unify those things and understand like the relationships we see in the particles are actually just different modes of those strings. Is it kind of like, you know, how different sheets of paper look all the same from the side? But maybe if you look at him from another dimension, they could have different shapes and colors. Yeah, absolutely. Or if you're a two-dimensional object in a three-dimensional world, the stuff that's happening in that third dimension can definitely affect what you see and you just aren't privy to it. And so you're seeing a little slice of what's going on and you can't understand the relationships between those things because they exist

in a dimension that you can't move in or you can't see. But string theory is also, it's just sort of beautiful mathematically. Like it all really fits together very nicely. And a lot of people are really attracted to it because some certain things just sort of like fall out of the theory. For example, string theory is a very natural theory of quantum gravity. You basically have to have gravity in your theory if you have a string theory. Interesting. It really pulls at your heart strings, is what you're saying. All right, let's get into what some of the other leading candidates are and let's talk about which one seems the most promising out of these promising candidates.

But first, let's take another 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 impelled 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. My boyfriend's professor is way too friendly, and now I'm seriously suspicious.

Well, wait a minute, Sam, maybe her boyfriend's just looking for extra credit. Well, Dakota, it's back to school week on. on the OK Storytime podcast, so we'll find out soon. This person writes, my boyfriend has been hanging out with his young professor a lot. He doesn't think it's a problem, but I don't trust her. Now, he's insisting we get to know each other, but I just want her gone. Now, hold up. Isn't that against school policy?

That sounds totally inappropriate. Well, according to this person, this is her boyfriend's former professor and they're the same age. And it's even more likely that they're cheating. He insists there's nothing between them. I mean, do you believe him? Well, he's certainly trying to get this person to believe him because he now wants them both the meat. So do we find out if this person's boyfriend really cheated with his professor or not? To hear the explosive finale, listen to the OK Storytime podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast.

I'm Dr. Joy Harden Bradford. And in session 421 of therapy for black girls, I sit down with Dr. Ophia and Billy Shaka to explore how our hair connects to our identity, mental health, and the ways we heal. Because I think hair is a complex language system, right? In terms of it can tell how old you are, your marital status, where you're from, you're a spiritual belief. But I think with social media, there's like a hyperfixation and observation of our hair, right? That this is sometimes the first thing someone sees when we make a post or a reel is how our hair is styled. You talk about the important role hairstylists play in our community, the pressure to always look put together, and how breaking up with perfection can actually free us.

Plus, if you're someone who gets anxious about flying, don't miss session 480. with Dr. Angela Neil Barnett, where we dive into managing flight anxiety. Listen to Therapy for Black Girls on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. Get fired up, y'all. Season two of Good Game with Sarah Spain is underway. We just welcomed one of my favorite people and an incomparable soccer icon, Megan Rapino, to the show, and we had a blast. We talked about her recent 40th birthday celebrations, co-hosting a podcast with her fiancé Sue Bird,

watching former teammates retire and more. Never a dull moment with Pino. Take a listen. What do you miss the most about being a pro athlete? The final. The final. And the locker room. I really, really, like, you just, you can't replicate, you can't get back. Showing up to locker room every morning just to shit talk.

We've got more incredible guests like the legendary Candace Parker and college superstar AZ Fudd. I mean, seriously, y'all. The guest list is absolutely stacked. for season two. And, you know, we're always going to keep you up to speed on all the news and happenings around the women's sports world as well.

So make sure you listen to Good Game with Sarah Spain on the Iheart radio app, Apple Podcasts, or wherever you get your podcasts. Presented by Capital One, founding partner of IHeart Women's Sports. All right, we're talking about the theory of everything or at least a couple of theories of everythings and talked about string theory as one of the most popular ones, but there are a couple of other theories that are up there, right?

They're still in contention for everything, for the whole shebang. Right, the whole shambang, exactly. So what are some of these theories? One of my favorite is sort of a generalization of string theory. String theory is an idea that's been around for decades and people were poking around and making progress and there were like a few kinds of string theory that had been developed and they only described like a little bits of the universe

or there was this kind of string theory or those kind of strings and how they interacted, the field was sort of fracturing to several different ideas. Then in 1995, Ed Witten, who's like one of the smartest people ever, unified them all together. He showed that all the different string theories that people had been working on were really just like sort of limiting cases. There were like extreme versions of one grander theory. So we had these like five different string theories and he brought them together into one theory that he called M theory.

Like the multi-string guitar theory of string theory. Exactly. And, you know, nobody knows why it's called M theory. And eventually somebody asked him like, hey, Ed, why'd you call this thing M theory? What does M stand for? He said, well, actually, he didn't know when he was waiting for us to like really deeply understand it. And then we could figure out what M stood for. I think he really just wanted to say, my theory.

It's my theory. And like, I'll just hide it as a physics nomenclature. Maybe. Or since his last name starts with a W, Maybe he's like, has a secret upside down W in there. Oh, interesting. Like the anti-version of him came up with this theory. Yeah, exactly, right.

And so M theory is sort of like a super version of string theory and includes other things like supersymmetry, this idea that every particle that's a fermion, like the matter particles, have a relationship with all the bosons, the force particles. And for every boson, there should be a fermion. For every fermion, there should be a boson. So it brings that together also into one larger theory. Instead of just thinking about individual strings, this allows us to think about like two-dimensional versions that they call brains, which is short for membrane, not like B-R-A-I-N, your brain.

Right, like maybe things aren't strings, but they're like little a napkin clothed, right? Yeah, like little sheets or three or four-dimensional. And so they have these arbitrarily dimensional objects, you know, one-dimensional, two-dimensional, three-dimensional. And so they call them about this rather ridiculous name, P, for the number of dimensions. and then P brain. That's a P brain theory, Daniel. It really is a P brain theory.

But you hear these like super smart people are really talking to each other about P brains, without any irony or giggles. It could think they didn't call it the opposite, brain P. Brain P theory. Well, you know, there are a lot of people out there who don't think that string theory

is the path towards a theory of everything. They think it's ridiculous waste of time and all just sort of mathematical conjecture. They're like theory everything. That's a theory of nothing. Yeah, exactly. Well, the real criticism of the string theory is that it operates at such a tiny level that we can't really test it. Like, sure, you're telling us maybe what's happening at 10 to the minus 35 meters, but how do we know? We don't have a collider that can do experiments yet at that small scale.

And so it's just sort of like a story we're telling, but not something we can test. Really, the only test of string theory so far has been a search for these super symmetric particles, these extra fermions. and bosons that might be there to balance out the ones we have in the standard model. And we were supposed to find those at the large H-on Collider, but we didn't. We didn't see any supersymmetric particles. So that's a bit of a blow for string theory. All right. Well, then if strings or little napkins or key brains are not maybe the best way to go,

what's an alternative then? Well, some people are coming out from a completely different direction. Instead of taking quantum mechanics and trying to incorporate gravity and making this big quantum mechanical string theory view of the universe, they're starting from gravity. And they're saying, instead of making gravity into a quantum theory, let's just try to quantize space itself. Like you were talking about earlier, space and time or fundamental elements of the universe.

We don't really know if that's true. If these things come out from something smaller, we don't understand what space is. So a lot of people are working on this theory called loop quantum gravity, which tries to take space and describe it as these little bits of like a quantum, quantum foam and have the whole universe sort of come out of that quantum foam. Like instead of having a like a perfectly smooth universe and space and time on which you have these quantum fields that are lumpy, maybe space itself is kind of crunchy and lumpy and not perfectly smooth. Yeah, maybe there's like a minimum distance to the universe below which it doesn't really make sense to talk about things being closer together than that because it's just not possible.

like all of space is like pixels on some universe screen. And so that's exciting. And people have been working on that last few decades. It's been some advances and revolutions. And it's seen sort of like as an alternative to string theory because it's a different way you might be able to bring gravity and quantum mechanics together. It's a completely different approach and it's made some progress. But the problem is that it sort of just brings gravity and quantum mechanics together.

It doesn't actually unify all of the forces. Like I can't explain why. we have electromagnetism? Why do we have the weak force? Why do we have the strong force? But it's, you know, progress in that direction. Right. I guess you can, if you, you know, make space itself quantum, then that doesn't explain how, what, like, particles can interact with each other across the distances. Is that kind of the limitation? It's not really a limitation. It's just like they haven't gotten there yet. They're still building the foundational building blocks. It's not clear necessarily how you would get there. It's not ruled out. It's not impossible.

But so far, the scope of loop quantum gravity is not to describe all of it. It's just to make this step of bringing gravity and quantum mechanics together. Once you do that, you collect your five Nobel Prizes, you know, take a day off, and then you can start working on the other parts of the theory. Right. Well, so those are some of the respectable toes. You know, that's the big toe, the middle toe of physics. This is feet and feet.

But they're also sort of like these less respectable toes or, you know, kind of the pinky toes of the universe. floating out there. The theories that are not quite as popular or mainstream, but that might be exciting. So Daniel, real quick, tell us what are some of these fringe theory. Right. Well, theories of everything are a popular target for people who are not in academia. We think, like, maybe the physicists have just sort of gotten it wrong. And what it needs is like a fresh idea from somebody who's not entrenched in all of these ideas and the history and the incremental progress that come in with a brand new idea and blow it all up. And so, for example, Steve Wolfram came out last year with the theory that he thought might be like the foundations of a theory of everything.

He's a smart guy, he's a guy who developed Mathematica and he is a physicist. He has a degree in physics. And his basic idea, which we dug into once on the podcast, is that maybe the universe is made out of these cellular automata. He envisions that the universe is made out of one kind or a small set of kinds of tiny things with very simple rules. And he studied this for a long time and shown, and many other people have shown, that if you start from simple things with simple rules, you can get complexity. And we know that already. Like hurricanes are not written into the laws of the universe. They arise from quarks and electrons interacting in really complicated ways. So what he did was he showed that, you know, you can sort of have like cellular

automata that write the rules of the universe. If you start from a few simple ideas and then a rule for how those ideas can change, they can sort of like write the rules of the universe. And he looked at what his cellular automata produced and they sort of looked physics-y and he was like, aha, look at this. Maybe this is how the universe was generated. All right. So that's one kind of fringe idea that, you know, maybe you can make a universe out of very simple building blocks, cells. What are some of the other fringe theories? Well, there were a couple engineers who took it upon themselves to write a theory of everything. This is a theory that's called the Fragments of Energy Theory by two guys in North Carolina called Silverberg and Ice.

and they were thinking about energy and they were noticing that like energy seems to flow. Doesn't ever just sort of like hang out. And they thought, well, you know, maybe energy is the thing. And like energy always flows through the universe and you can think about it is flowing through these lines. And maybe you can quantize it and like break it up into these little packets and think about how it flows together. So they wrote down some rules for how energy flows and how to break it up and how these

packets of energy would then interact. And they were able to do some cool stuff with it. Like they twisted it a little bit and added a few bits and they were able to reproduce some predictions of general relativity. So they thought that was pretty cool. And they put this out there to quite a lot of fanfare, actually. It hasn't landed very convincingly. Like I think most of academic physics was like, eh. That was a paper review.

Reviewer number one says, eh. Reviewer number two says, eh. Is that the most hurtful review you can get in physics? like not something dissecting your math or telling you why your hypothesis is wrong is it's indifference you could imagine revising general relativity or like reimagining it in some different conceptual space and reproducing it that's cool but it's not like a new theory of everything so they haven't really like made any progress in fact their theory doesn't quite reproduce general relativity they need to like add some by hand numbers to squeeze it in there to get things right like

you know the procession of mercury and the bending of light around the sun stuff Einstein got right 100 years ago without having to tweak or tune his theory at all they got to sort of like put this in a little bit by hand so it's not really clear that it's progress it's not like a way forward it's just like here's another way of looking at general relativity that makes more sense to us and also doesn't quite work as well so not necessarily like really that exciting it doesn't seem inevitable or a shoe in right away and it also doesn't necessarily tell you what to do next like the exciting thing about string theory is that there's things to explore. There's puzzles to solve.

They're like, oh, we can try this different compactification of those other dimensions. We can try this one. We can try that one. There's areas where you can make progress. Here it's just sort of like, oh, that's interesting. I'm not sure what to do next with this. All right. What are some other fringe theories? So another one that got a lot of attention was by a guy named Eric Weinstein. He also has a PhD in physics, but now it works at a hedge fund. And he's a, you know, very well-known guys on podcasts all the time. And he has a theory called Geometric Unity that he came out with about.

10 years ago. And he basically just takes all the theories we have now and sort of stacks them on top of each other, sort of like an ice cream sandwich and says, I'm just going to stick them all into one container. What do you mean? Like quantum gravity, like quantum physics and general relativity, you can stack them? Well, he doesn't have quantum gravity in there yet. And so he's just taking all the quantum theories and stack those together. And, you know, like, I'm not really sure what you accomplish in doing that. It's just sort of like groups them. It doesn't necessarily like show that they're part of one larger hole or that they have a deep relationship. He likes the way they've stuck together, but there's no simplification that's achieved

there in my understanding. I see. It's still pretty unsupported, I guess. And another issue with it is that he hasn't yet written a paper about it. So it's been out there for about 10 years and he was invited to give a talk about it at Oxford and he came and he presented it. The problem is that like nobody invited all the physicists at Oxford. And so.

And that heard your feelings. So now you're just down on the theory. No, and in academia, you know, we need to see a paper. We need to, like, see all the detailed description so we can, like, think about it and play with it and read about it and talk to each other about it. And he's actually recently promised to put a paper out. Maybe they asked him, why doesn't he write a paper?

And he just said, eh. And you're like, ooh, you got us. You got us. And other mathematicians that have looked at what he said sort of digested what he said in a podcast and in his one presentation has said that they found it mathematically inconsistent. You know, there are reasons why we haven't stacked all these theories together.

They don't play nicely together. There are anomalies. There are things that don't make sense. There are inconsistencies that happen if you try to jam them together and you don't find the right way to do it. It doesn't seem like he solved those problems. But we'll just have to wait to see what his paper says. All right. Well, those are some pretty interesting and promising fringe theories.

And we also have some core, more popular theories. I guess just two sort of closes out here, Daniel. Let's talk about really quick about whether or not you think it's, even possible to have a theory of everything? And even if we find one, would it be useful at all in helping us in our everyday lives? Yeah, it might not have immediate engineering applications, right? Even if you understood the universe at its smallest scale and all its littlest rules that wouldn't help you understand when a hurricane was coming or, you know, how to get to the neighboring galaxy necessarily. On the other hand, it might reveal something deep and fundamental

about the universe that would give us immediate applications if you like uncovered a new force or let us tap into and control dark energy the biggest fraction of the energy budget of the universe that could very much really change our lives we never know what this understanding will reveal on either hand it could allow us to create terrible weapons and then we could wipe each other out so you never know what the future holds could be useful it could destroy all humanity you know we don't we don't really like to think about those practical consequences yeah yeah exactly from the worst possible outcome to we are now masters of the universe. Basically, that's the spectrum we're talking about here.

Then you just blame the engineers and politicians. Exactly. I was just eating some ice cream. It wasn't my fault. I was just sitting here, snacking on ice cream and being flabbergasted. And all of a sudden, we're all dead. And if that worries you, you know, there are people who argue that maybe it's impossible. You know, there's this famous theorem, this Godel's incompleteness theorem that says that all

mathematical systems are either inconsistent or incomplete, you know, that either they contradict themselves or there are things that cannot be proven. What? What is this theory based on? How can it say that everything is, wouldn't it also be inconsistent itself? Oh man, we need a whole another podcast episode to dig into goals and completeness theorem. So let's put a pin in that. But it's a formal theorem in mathematics, which people think is right. You can argue about what exactly it applies to and whether it applies to physical theories or just to axiom-based mathematical systems. But some people use it as an argument to say, like, maybe there's a limit to how well our mathematics can describe the universe.

You know, it doesn't say that the universe isn't physical or doesn't make sense, but maybe like our mathematical systems, which are based on these axioms, are just not the right language for exploring the universe. You know, it's not guaranteed that the universe can be described by mathematics just because that's the way we'd like to think about it currently. So what would it be? I guess we can talk about it another time, but if not math, then what?

I don't know. We'll have to meet those alien physicists that have developed something else. What's the foundation? What's the language of their physical theories? Maybe it's not mathematics, right? Just because we can't imagine it doesn't mean it's not reality. All right.

And like you said, it might not even be possible to confirm these theories in the end, right? Because we're talking about scales for which we really don't have a microscope to go and check. That's right. Until we build a solar system-sized particle collider, you know, send in your checks, we can't really test these theories. And it might be that it just keeps going on forever. Like you might find what you think is the smallest theory, but it just keeps going down and down the rabbit hole.

Exactly. It might be that there is no smallest scale and that there's just like an infinite layers to this onion. Hey, that's an idea. Onion ice cream. Maybe that's the unifying theory of everything, Daniel. The infinite onion flavored ice cream. Wow. I'm flabbergasted.

And while it's fun to think about the theories of physics that sort of physicists are thinking about, a lot of people out there are thinking about theories of everything. And sometimes they email them to me. I got an email from one of our listeners who had a fun idea. He says, quote, maybe our observable universe is actually the nexus of two different overlapping universes, one for quantum mechanics and one for general relativity. And that's why we can't unify them. So it's interesting.

Yeah, it's fun to think about. it's sort of tantalizing because everybody knows this is a big goal in physics and physicists that are struggling to get there and it would be fun to sort of like have that moment of inspiration and see the truth of the universe and then reveal it to everybody and eat some ice cream

while you win your Nobel Prize. Then you can be flavor gasted too and live in the halls of truth. That's what we all aim for. I think that should be the name of our ice cream pop-up stand, flavor gasted. Let's do it. All right. Well, hopefully we'll make some progress in the future. In the meantime,

Try not to stub your toes, Daniel. And don't eat too much ice cream. Well, we hope you enjoyed that. Thanks for joining us. See you next time. Thanks for listening. And remember that Daniel and Jorge Explain the Universe is a production of IHeartRadio. For more podcasts from IHeartRadio, visit the IHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.

December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, everything changed. There's been a bombing at the TWA terminal, just a chaotic, chaotic scene. in its wake a new kind of enemy emerged terrorism 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 my boyfriend's professor is way too friendly and now i'm seriously suspicious wait a minute sam maybe her boyfriend's just looking for extra credit well dakota luckily it's back to school week on the okay story time podcast so we'll find out soon this person writes my boyfriend's been hanging out with his young professor a lot. He doesn't think it's a problem, but I don't trust her. Now he's insisting we get to know each other, but I just want her gone. Hold up. Isn't that against school policy?

That seems inappropriate. Maybe find out how it ends by listening to the OK Storytime podcast and the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Get fired up, y'all. Season two of Good Game with Sarah Spain is underway. We just welcomed one of my favorite people, an incomparable soccer icon Megan Rapino to the show and we had a blast. Take a listen. Sue and I were like riding the lime bikes the other day and we're like

we're like people ride bikes because it's fun. We got more incredible guests like Megan in store plus news of the day and more so make sure you listen to Good Game with Sarah Spain on the IHeart Radio app, Apple Podcasts or wherever you get your podcasts. Brought to you by Novartis, founding partner of IHeart Women's Sports Network.

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