What came before the Big Bang?

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Speaker 1: What if you thought, as an adult that you've been alive forever and then you discovered no, you actually had a childhood and you were born, and you would want to know all about that. It would be surprising. And actually that's sort of the situation science was it. For a long time astronomer thought the universe is fixed, it's constant. All the stars are just sort of hanging out there in space, not moving, and they've been like that forever. Hi, I'm Daniel, is this Horran? So? I'm a particle physicist. I smash protons together at certain in my day job to try to figure out what is the basic nature of matter? What do you smash as a hobby ban? Yeah? You know, when you're a particle physicist, you learned to solve problems by smashing stuff together. So whatever's around me, And I'm a cartoonist and my job is to sit in my pajamas all day and for funny things. That's not how you started, right. You didn't grow up thinking I'm going to be a cartoonist. No, I started off as a researcher. I'm an engineer. I studied robotics. I have a PhD in robotics. But um, somewhere along the line, I started joining comics and that kind of took off for me. And this is our podcast Daniel and Jorge explained the universe. Today, we're going to talk about how it all began. The biggest of questions, the Big Bang. What happened at the very beginning of the universe, What happened before the Big Bang? It's a pretty deep basic question about the origin of our universe. What do you think about it, what do you know about it? What do you imagine might have happened before the start of our universe. We went out and we asked people on the street what they thought happened just before the Big Bang. Um, well, there was a bunch of particles in the universe, and then they combined together and had all the energy of the universe. So then when it happened, that's how it was all dispersed. So most people seem to have some idea that, first of all, the Big Bang is more than just a TV show, right, that the idea for the science came before the TV show. I was kind of relieved to hear that everyone seems to know it's uh. It sort of marks the beginning of the universe. Right, it's a moment of creation or the starting of the clock of the universe, and everything came from. But what exactly happened during the Big Bang? And most interestingly, what happened before the Big Bang? Right? And that's that's fascinating to me. And these are the best questions, the ones that like try to answer the question where did everything come from? This sort of touches on the philosophical like why are we here? If you knew how the Big Bang happened and how the universe was created, you might get some insight into like what the purpose of life is or how to live your life or stuff. So to me, these are like really good, deep, basic questions. So we made a list of the four things we think you should know about the Big Band. The first one is that the entire universe was once really small. Maybe we think, let's talk about that. What do you mean maybe, Well, it's an interesting question. We know that the universe had a beginning, right, And how do we know that? We know that because things are expanding, things are moving away from each other. That was the major discovery, Like a hundred years ago, people looked out in the stars and discovered that they're all moving away from us. Okay, So like we thought everything would still like we were frozen in a gel or something. The stars were just like they're sitting there, generally speaking. But then they discovered that they actually things are moving away from each other, that's right, And everything is moving away from us, and everything is moving away from everything else. They just looked at stars, and you can measure how fast a star is moving relative to us by by seeing how it's light is stretched or shrunk, depending on whether it's moving away from us or towards the second dopler shift, like the highway patrol measuring your speed, you can sort of you can tell how fast you're going. Yeah, exactly. It's not like they looked at the stars and said, oh, now it's that once over there, it must have moved. It's like that's some other information, right, right, So they looked out there and they measured all this stuff, and they said, whoa, everything's stretching out and moving away from each other. So then the very natural consequences to say, well, run that backwards. What does that mean? It means things might have been smaller and more dense and maybe even come from a little spot like if you had the rewind bunt. If you see things maketting bigger, now, if you had the rewind bunt, wow for a while, what happens exactly? And those are the mental games people were playing. And actually the phrase big Bang was a joke that people made up to mock that idea. They're like, look, how ridiculous this idea is. It's kind of a silly sounding name, right, Yeah, it was like whimsical. It was. It was like a Donald Trump insult, you know, for somebody else's big Lee Bang. Yeah, the big Bang. Well, if you were like a respectable scientist today and you had to name this event, you wouldn't call it the big Bang? Or do you think that it was a good name? Oh man, if I was on a marketing committee, discover a new name for it, the moment of creation. Um, now, I think big Bang is actually pretty good. Yeah, you got your literation. It's short, it's pithy, you know, it's it's pretty well done. I think that's probably why it survived so long, because everyone wants the universe to start with the bank. That's right. So you played back the movie of the Universe, and it tells us that everything was once much closer together, and then much much closer, and then much much closer, and if you keep thinking about it, things may have been really really really close together. That's right. Yeah, they just keep extrapolating down to a point. And around the same time Einstein came up with all of his ideas of general relativity and thinking about gravity and how the universe works, and people were playing with those equations and discovering that those equations actually predicted that the universe could start from a point. They were consistent with Einstein's ideas of gravity. What you mean consider it was consistent, meaning that that it, um, you can construct a universe that starts from a point and then it blows up and expands, And that totally makes sense from an Einstein gravity point of view, like it follows the rules. It's allowed, meaning that nothing weird happens, like you can cram that much stuff into such as small space according to Einstein, right, which is pretty well accepted as a smart guy, he knows what he's talking about. But you know, there are some issues there. Um. The original idea was the Big Bang was this really dense hot blob of stuff and then it blew up and expanded into things we know, and you know, that was a weird idea for a long time, and people didn't believe it for a long time. It was in the sixties that they finally found the first like concrete piece of evidence that maybe the Big Bang had happened. And that's when they discovered the thing called the cosmic microwave background radiation. So it was weird to think about so much stuff and matter and stars and being cramped to small space. Yeah, because I meant the universe wasn't always this dark and cold and empty place that we know today. It was like a hot, dense blob like the center of the sun. It was a hot mess exactly. The universe was not well organized when it was young. Um. So yeah, so they said, okay, now, but now they saw something like you call it the cosmic microwave background radiation that said, yes, that's a clear indication things were a hot mess before. Yeah. They said, if things were really hot and dense a long time ago, then they should have given off this special kind of light and we should still be able to see it today. And they went out and they found it. You can see it like you can see it if you have a special radio telescope, and some guys built a fancy radio telescope. They weren't even actually looking for this background radiation and they just had a hiss in their in their telescope. They had this noise in their telescope. And coincidentally, some people a couple of years earlier had predicted, oh, if you build this kind of telescope, you'll and the big Bang happened. You'll hear this hiss and they turn on their telescope. They heard this hiss and they're like, what is this. We can't get rid of this noise. And then two years later the one the Nobel Prize. That's a great discovery. It was a pretty happy you're gonna get fired, but then they're like, oh, that mistake you made. It's the discovery of the universe. That's right. So that's a big bang. It's everything was once really small and then it's just gonna explode it out into what we have today. That's right. That's the whole idea, is that the universe has a beginning and then it expanded into what we know today. Um, And that was the sort of first idea of the big bang, like maybe everything came from a point, and people, a lot of people, when they think about the Big Bang, they think about the universe starting in a singularity, meaning a bunch of stuff in zero volume, all of it on top of each other, in the same zero space exactly. And it's mind blowing to imagine, Like, take out the Sun and cram it down into the amount of space you have for a grain of sand. Hard to imagine, right now, make it even small. Now at every other star in the universe on top of it. It's like your brain in the same thing, right, Yeah, it's it's not really the same thing. It's just all the energy, all the all the energy density that we can have in the universe was cramed into that tiny little space. That was sort of the early idea. And you can imagine like a big empty universe of space with a tiny dot of matter in it, And of course that engenders a lot of questions like where did that tiny dot a matter come from? Right? Was there only one? Um? How was it created? Right? But before we keep going, let's take a short break. Well, so that's a big bang, and so the next thing people should know is that the Big Bang happened about fourteen billion years ago billion with a b billion years ago and I can't even remember what I did this morning fourteen minutes ago. That's how old universe is from that moment of the Big Bang. Yeah, so the universe has been around since the Big Bang about fourteen billion years and you know, for scale, the Earth has been around about four and a half billion years. That's when our solar system was formed. Well, how do you how do you how do we know how old the universe is? Like, yeah, like how can you tell? Yeah, well, we are seeing it expand and so the simplest way is to just extrapolate back, say how fast is it expanding? And extrapolate that expansion back until the zero point. So like if you look at it, the furthest stars you see, you know how fast we're going. You can just like hit the rewind button. It would take about fourteen billion years for it to connect to everything else. Yeah, so we're pretty sure that something happened fourteen billion years ago. This expansion of space happened fourteen billion years ago. But these days scientists are a little fuzzier on what exactly the Big Bang was. So idea zero was a tiny dot with all the matter and explodes into the universe um. Problems with this idea are one that you can't really have tiny dots of infinite density, so Einstein told me before you could. Well, that was Einstein's idea, and the idea is consistent with Einstein's gravity, but Einstein's theories of gravity don't account for quantum mechanics. Quantum mechanics something that came after Einstein he was never really very comfortable with, and quantum mechanics is a whole, big, long story. But the thing we need to understand is that it says you can't have things that are super duper tiny. There might be the smallest space, there might be the smallest distance. Yeah, like at some point you can't get unfuzzier. That's right, exactly, it's a basic unit of fuzziness. Like imagine space being pixelated, right, Like you can't talk about something smaller than one pixel. So we think that quantum mechanics is probably correct. And if the big pixel, that's right, the first pixel in the universe. So we think if you try to follow Einstein extrapolate the universe down to point general relativity probably works, but we think it probably breaks when you get down to really really tiny distances and really heavy stuff. But nobody's ever seen that happen. You have to look inside a black hole or go back in time and see the Big Bang. But these days we have a slightly fuzzier version of the idea of the Big Bang. Rather then a point of matter that then explodes into space, we think of the universe is being created as a blob of space and matter and then and matter. Yeah, so like it was, it's a like a blob of space, like a tiny universe with not much space. So instead of an infinite universe with a tiny blob of matter in it, now imagine a tiny piece of space filled with energy and matter. Okay, and what's outside of that little space we have no idea, Like seriously, we can't even imagine inconceivable, right, But we do know that space can be variable in size, space can expand, and these days we have a more modern idea of the Big Bang as that expansion of that space kind of like a bubble, Like a bubble that's a space, and then there's stuff in the bubble. So you're saying both those things blew up exactly. And this is the more modern idea that space itself can expand. And so if you're out there thinking, what is he talking about? How can space expand? What is it expanding into? Everything has to be in something, right, And the answer is, we don't know. We think used to think of space is just like emptiness, and we can go a whole episode about just what spaces and I think we really will, so keep listening. But these days we think of space as a thing because it can expand, it can bend, and it can ripple, so we know it has all these properties. So it might be that this bubble of space in the early universe was in some sort of super meta deep space that we have never really discovered, or nothing. It could be that it doesn't have to hang in something else. It's just the edge. And space itself was smaller that that much. We know space was small. Space was smaller, and the stuff in it was crammed in really really small to try it. And then about fourteen billion years ago, for some reason do we know why, and we don't know why, it decided it didn't want to be that small anymore, that's right, Yeah, And that was the moment that space was created and then it expanded like crazy. It's something we call inflation. Inflation is not you know why your money doesn't work as well in every year? I mean that is inflation. But there's I don't know why do we do this? In science? We take an idea, a word that everybody uses to mean one thing, We just like use that same word to mean something totally different, but it fits when it describes it. In the universe inflated like a balloon, like a bubble, right, yes, okay, it's a good descriptive name from that sense. So the universe inflayed, that whole balloon inflated, and everything inside it got stretched. And the amount of stretching that happened is crazy. It's like the universe expanded in space by a factor ten to the thirty. That's ten with thirty zeros on it, some crazy huge number, and it did it in this really small amount of time. Tend to the minus thirty. So that zero with thirty zeros after the decimal place, and then a one. So this incredible expansion, a huge expansion of space have tended the thirty in this tiny amount of time, tend to the minus thirty. It's hard to really even fathom. It was in a rush to get big yes, and it's still getting bigger today. And the other things that's important to understand is that space didn't get created like on the outside of the universe, like they made more room. It's stuff. The space inside the universe stretched and kind of created, so like between two particles you had a certain amount of space, and all of a sudden you had extra space between particles. So the more things, Yeah, everything is getting stretched out from the inside also not just from the outside, and that's also continuing to happen, like the expansion of the universe today. The in fact the universe is getting bigger and bigger is happening all around. This is more space being created. The third thing we should talk about today is uh that we don't know what happened before the Big Bang, like before this little bubble blew up, what happened before. But before we get into that, let's take a quick break. This is like totally territory for speculation and philosophy. Um, we have pretty good theories about what happened during the Big Bang. This idea of the inflation, we even have some experimental evidence for to back it up, and it's pretty solid theory these days that inflation happened. But what do you mean experimental? Like, we can't measure the Big Bang? Can we write? So we can't go back in time and see it right, Um, But we can do things like detectives do after a murder, and we can look for clues and say, are the clues that we've see in the universe today consistent with this story or with that other story. So we can sift through the clues from the Big Bang and say, it looks like the universe was created, and if inflation happened, it probably created these ripples in that plasma. We can see those ripples in the cosmic micro background radiation. It's really an incredible golden age of cosmology. They're doing all this really precision work to understand exactly what happened and what we know. So, but we can only see up to a certain points. We can only see before that is just the speculation. Before that, it's just speculation. So one popular idea is that there's this kind of matter called inflationary matter inflatons, and it has some weird gravitational properties, and those gravitational properties cause inflation, Like suddenly they came into being inside of this hot mess and it's like we need to get out of here. Yeah, it's this never ending loop of questions. Right, So you say, well, in the Big Bang was inflation? What caused inflation inflationary matter? Well, what created inflationary matter? It's like dot dot dot. You could just keep asking that question forever, and I think we will be asking that question forever, will always be pushing back and trying to understand, and until we get back to negative infinity and time, we're never going to have like a solid answer. But that's part of the fun, right, It's not like it's the journey as much as the destination. But there's some cool ideas there about what happened before that point, right, that's right. Yeah, Like maybe, um, the whole universe was filled with inflationary matter and in some places it decayed into normal matter and then inflation happened. And if that's the case, then you have like our universe is one spot inside some huge mega universe of inflationary matter, and maybe at other points in the in that mega universe there are also other dots that turned into what we call pocket universes, like it of the in the space of the of the mega universe, Mega zits on the mega universe and that maybe maybe like our universe is just like a little bubble in a big sea of other bubbles. That's right, exactly, that's one idea, and um, we have no way to really to test that idea is the problem because there's no way for us to ever reach those other bubbles. Because if that's the case, if that's really the reality of our, of our the situation of nature, it means that inflation is still happening because inflationary matter is still constantly expanding. So those other universes, those other bubbles are getting pushed away from us much much faster than the speed of light. Because it's never like hang out. You can't send a message there, you can't ever see it, you can't ever go there. And scientifically that's a big problem. Um, not because I really want to go to the beaches and some other bubble universe, but because if you want to prove that it's true, you have to do an experiment, you have to find some evidence. You have to do you have to have a theory that can be confirmed. If if you have a theory that predicts something you can never test, and it's not really a scientific theory or a useful one. It's it's like, yeah, it's a guess and uh, next one theory, maybe were a bubble in a sea of other universes. What's another idea for what happened before the Big Bang? Well, another idea is that maybe there's a cycle, right, maybe the Big Bang was caused by a big crunch, right. And to understand that, you have to think about sort of the future first, Like, so the Big Bang happened, every expands out, and then one question is like, are things going to keep expanding? We don't really know, but one possibilities they keep expanding forever in the universe just sort of drifts out into this endlessly cold, boring, bland situation. But another possibility is that it slows down, stops, and then falls back in. Everything rushes back and gravity pulls everything back into a to recreate a hot plate. Yeah, deflation, Well, I think you just invented. Can I go back and change it to my son's name oliveration. The deflation theory would say that the universe comes back, falls and then collapses back into a little hot mess again, a little hot mess. It's like recovering your youth, right, it's like a middle age crisis or whatever, and then it just bounces out again. Yeah, and that would be a cycle. So a big crunch, big bang, big crunch, big bang. That could be big bang US, big crunch, big bang again. Maybe somebody else, somebody else yeah, impossible, impossibly um Yeah. So that that's been Another idea is that what happened before is like more and more universes. Yeah. And there's something nice about that because it explains both that the our universe had a beginning and also gives you an explanation for what happened all the way back to the beginning of time because it returns to the possibility of the universe is infinitely old, right, because that could have been happening forever. It allows you to have this sort of finite length of time for our universe without limiting you to finiteness for the whole universe, sort of like this time could be infinite, but space could be finite. Yeah, that's right. Yeah. And that brings us to the last crazy idea, which is maybe there was nothing before the Big Bang. I mean nothing, not even time. Right. We think space was created in the Big Bang, and spaces expanded and all that stuff, and so so there could have no time, no space before, no space and no time, right, And it's hard to even wrap your mind around what that is. I mean, we have a hard time imagining, like, what will happen after we die? Well, the universe continue without us right now, trying to imagine the universe without space and time? What does that even mean? And you have to think also about what time is itself? Like, what does it mean for there to not be time? Right, there's no time in which there's no time. There's no time for that to happen, right, um, And a lot of people think about time as sort of the organizing principle of the universe. Maybe you've heard of the second law of thermodynamics. It tells us that entropy is always increasing in the universe, and so they imagine things are getting messier, Things are getting messier inward, that's right, getting more and more spread out forward in time. And so some people think that that is time, that time is measured by entropy and created by entropy, and that before the Big Bang, if there was if there was nothing, no space, then there was no time. And that sounds like an odd idea, but in other ways, we're very familiar with it. Like you know, if you stand on the north pole and you asked which way is north, well, there is nothing north. You blew us up. I'm gonna write to Stephen Hawking and tell you, um, that's actually his his phrases. You know, maybe there's no north of north north. There's no before zero time. Yeah, because if you're standing on a sphere and you're the north pole of it, there's nowhere to go, no more northiness, there's no you can't the tape ends when you try to rewind it more. That's right, and that's something we're comfortable with. We're accepting the fact that a sphere has like a limit and edge, and it's reasonable for that there be nothing beyond it. But when we think of time, we tend to think of in a line, and so we want there to be something before it, or at least for there to be a reason why it started here and not somewhere else or some other other you know, time or um. It's a very natural, i think idea to have intuitively to think that something should have been before then. But it could be that there was nothing, that the things were created at that moment and there was nothing before there, and then we came, Yeah, we dropped the mic, we came, we made this podcast, and that's the summary of the whole universe in a nutshell. And you know, any of those theories. First of all, those are very difficult to test, and it's hard to imagine how we'll ever know. Right, it might be that there aren't any clues in the rubble of the universe to tell us which one is, which one is, which it might be, Although I'd like to have faith in future scientists coming up with clever ideas for ways to test these theories which right now seemed possible to test. But in the future people can be everybody able to see beyond the Big Bang. Yeah, maybe maybe they'll find some evidence in the current reubble that tells them it is this, or is that, or is the other thing? But even if you get there, imagine having an answer to one of these questions, Right, what do you think knowing what happened before the Big Bang would tell you like, how would how would it change your life? I think it would change everybody's life. I think it's a kind of knowledge that would filter into like the global consciousness. Think about how quantum mechanics has changed the way people think about things. But there's randomness in the universe, or the universe is not following a fixed set of rules, but that those rules have fuzz in them. You think it's It's changed the global consciousness way absolutely, and not just in New a g people who you know, but in everybody thinking about the universe is being a little different from what they imagined. Do you have a question you wish we would cover. We 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 Daniel and Jorge dot com.