The “Bang” in Big Bang with Charles Liu

0:00So Paul, those are some fun questions in a cosmic craze grab bag. And from all over the world, literally. All over the world. And, you know, what I think what people are going to see in the upcoming episode is that we pretty obliterate time. Time. Time succumbs to our logic and rational thought. Coming up on StarTalk. Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now.

0:36This is StarTalk. Neil deGrasse Tyson, your personal astrophysicist. And I got with me as co-host today, Paul Mercurio. Paul, welcome back. Thanks. Thanks for having me. Great to be back with you, buddy. Yeah. This is the attorney, stockbroker turned comedian. Yes. Attorney, investment banker turned comedian. There's nothing funny about lawyers and stockbrokers. No, exactly. Okay. I found a way to like run from it as fast as I could. All right. So, Paul, we're going to do grab bag cosmic queries. We are. We got some great queries here. And I don't trust myself in grab bag mode. Yeah. I need backup.

1:13Yes, you do. I got to go for the big guns. You need your Starsky. You're a hush. Starsky and Scots, yeah. Wait, I'm Starsky. You get 70 to get that reference. He did pull up in a Ford Torino. Charles Liu, welcome back to StarTalk. Hi, Neil. It's great to be back. Charles, longtime friend. Our families are friends. Absolutely. and with colleagues. You were here when we built the new Rose Center for Earth and Space 25 years ago. Has it been that long? It's been a quarter century. Jeez, it feels like yesterday that I came over here and this place was a hole in the ground. Yeah, it does feel that way.

1:46And it was, you have intellectual and sweat equity in what we built here. So we're thankful for that. It was fun. That's weird, because when we were talking, he wasn't here, you said he didn't do much. You took a lot of the credit. I don't know. Well, you know, he's not wrong. I mean, I was just hanging out here all night having a great time. Yeah, that's all it was. Just jump right in. Okay. All right. Let's do it. This is Galaxy. Hey, Dr. Tyson, Dr. Lou. But Galaxy's the person. Yeah, Galaxy. Galaxy, okay. That's there. I am Brian from Roseville, California. I just recently joined the Patreon, and I'm excited to have my question answered.

2:25Welcome. Yes. Thank you. I'm going to say it right. Welcome to the universe. Okay. We dim the lights when you do that. Woo! I have always wondered how giant gas clouds and nebula exist in space. Shouldn't the vacuum cause all gas to disperse evenly to the point of not being, even being able to see it? I love that, because on Earth, any cloud of gas disperses. That's right. As dogs know. That's right. Dogs will smell you from far away because whatever is your stank. Yep. One minute in, and he says, the guest has stayed. This is a lesson anybody watching on how not to host a show. At least it's not smell-o-vision.

3:12Goodness gracious. Yeah, so it does dissipate. It's a great question. You look at blood in the water, and that— Does it dissipate evenly? Well, it's a diffusion equation where you have molecules. It wouldn't happen in solid because all the molecules are just rigid. but in a fluid. They can vibrate. But you're not going to move it through the system. There's a phase issue. I'm saying it's not going to move through the system. Just trying to get technical. Wow, this is getting tense already. Well, he called me skank. I mean, what am I supposed to do? I didn't say skank. I said stank. We don't need this.

3:48We'll do our own show. There we go. Let's go. So the diffusion equate, so you have a molecule that can move like all the others and it just works its way through. In my high school, there was a diffusion experiment where there's a long tube. It was one of these displays, because we didn't have any athletic trophies to put into a geeky high school. So you got to put other stuff in your hallway, display cases. There's a hall of beakers? Yeah, one of them is a very tall beaker. Yes, about this tall, if I remember correctly. That was littler, not much littler, but I think it was this big. And there was ink at the bottom.

4:29and they carefully put water on top of it. And throughout the year, you got to watch, because the ink is slightly denser, but still they're both fluids. And so you get to watch the ink work its way up real slowly. At my high school, they had diffusion experiments every afternoon after the school lunches were served bean soup. And in every classroom, there would be an experiment of different particles suspended in the atmosphere if you're moving from one side of the classroom to the other after you first heard that something was coming. And people didn't figure out to not eat the bean soup. Right, exactly.

5:06And that's where you got your name, Skank. Skank, Skank, Skank, Skank. So did you, could you do that same with ink? Could you do it with oil, like cooking oil? Yes. Would it work? No, because oil would float and the miscibility between oil and water is very different between, because ink is, most inks that we use today are water-based anyway. So the water is finding the water molecules. So Brian, the answer is basically the conditions out in space make it so that these gas particles tend to disperse unless they have a reason to collect. Okay, here on Earth, you have different kinds of things like buoyancy involved and things like that.

5:49That also happens in space. But in space, when the temperatures are very low, say 400 degrees below zero Fahrenheit, gravity can actually overcome a lot of the emotional sort of dispersive, diffusive. Emotional? Emotional. Emotional, okay. Yes. It could be emotional. You know. I ain't doing this. It's very moving. That's right. You tear up. You start crying a lot. Emotional, I never heard that word. Okay, emotional. I have to become a star. Oh my gosh. Yeah. Yeah, some guys have to become stars, yeah. Yeah, when it's cold, the random motions of the gases are actually overcome by the mutual gravity that they exert on each other.

6:29But does it happen, is it dispersing in an even nature? Not at all. Everything is turbulent. If you go see, for example, beautiful pictures of say the Orion Nebula or other interstellar clouds, you see that they're streaky and strange and unusual shape. They look like horse head, they look like helixes and cat's eyes and things like that. And that's completely because the turbulence is still going on. Is it that or because you're smoking something funny? That too. You know? Both work. We got to ask these stars that are emitting their planetary nebulae, what are they smoking? I think that would be a very, very good idea.

7:03But the bottom line is that in space, you have gravity holding these clouds together long enough for them to do things like form stars and planets. But there's always these forces and these different energies and so forth for trying to disperse them. And so you get beautiful combinations, and that's why you get beautiful nebulae, and you get things like stars and planets. I will add that you have a gas cloud that makes a family of stars. So that eats up most of the mass of the gas cloud. But there's part of the gas that didn't participate in the formation of the planet. A little snooty, like you were in high school.

7:40A little snooty. A little standoffish. It just wasn't. And that gas doesn't always land on a star. Do we know why in all seriousness? Well, now the gas doesn't have enough gravity to make it a next star. We're done. No, but at the time, and I'm not trying to be funny. It's too far away. So watch the rest. I got this. Like all the other gases had an equal opportunity part of that. It's not an equal opportunity system. If you're a little too far away, you might not feel the strong enough gravity to participate. And the stars form without you. And then the whole galaxy is rotating. Okay? So your whole system with your stars and your gas is moving and there's new other stuff.

8:20So your gas can get stripped and scatter into the galaxy never to make another star. So that gas just continues as gas throughout the universe. And these are the particles that comprise the interstellar medium, even between the gas clouds. It's not completely empty. Okay. And can that gas marry with other gases? Eventually, yes. Eventually and sort of possibly be part of another. It depends completely on like what Neil was saying. What is the rotational shear? What is the temperature in the environment? How much of it just happens to gather at this moment, whether it can actually collect or not collect.

8:56It's really beautiful and fascinating. But the funny thing is it is very, very sparse, right? Here on earth, we have trillions upon trillions of particles of gas, even in the tiniest, you know, beaker or vial. But out in space, just even a couple of hundred miles above Earth's surface, we're lucky if we even get one gas particle. It'd be the best vacuum ever created on Earth is just space. So people who study interstellar clouds are literally studying nothing. And yet that's the nothing from which we come from. Right, so it's endlessly fascinating. Such is the layout of this cosmic ballet, choreographed by the forces of gravity.

9:36It's more like a Martha Graham kind of. Ballet makes it too orderly. I don't know. I'm feeling Alvin Ailey. Okay. We go Alvin Alley. I've been buked. Wins every time. All right, we're moving on. Great question, great answers. Christopher Wynn. Hello, Dr. Tyson, Dr. Lou. I am Chris Wynn from Ottawa, Ontario, Canada. I'm new to Preach and I love to show you. My question is, during the Big Bang, what went bang? If we don't know, what are your best guesses? There's only one answer here. It's the universe went bang. Right. Okay, next question.

10:12I could take that. Well, we know the idea. I've got that one. We know the idea of personal space was blown to us, right? Look, the term Big Bang was actually coined by or attributed. But it's so misleading because it's about expansion. That's right. It's not about bang. It's attributed to. And why don't you guys fix that? I've tried. I've tried. There's a lot of legacy language that permeates our field. and it makes it historically interesting. Can I ask a question? No. In all seriousness, how would that process work within the scientific community if you wanted to sort of take on the task of changing the terminology?

10:52Oh, you mean like if you change the status of - Pluto, don't even say it. Stop it, stop it. I'll kick you out of this office and throw you off the roof. No, say it. I'm already stank, so I mean, why not, right? Think about it, stank. No, no, no, no. Wait, no, no. Go ahead, go ahead. Two very important points here. So finish your Big Bang story. Okay. The Big Bang term is attributed to a guy named Fred Hoyle. It was an interview done early on in the middle of the 20th century. Back when ideas for the beginning of the universe were still uncertain. Right. And they were still contesting. Right. And so he himself did not like the idea that the universe started from nothing or something very small and became something big.

11:30And so the journalist that he was speaking with or interviewer or whatever said something like, So you're thinking of the universe is kind of like a big bang of some kind. And that just stuck. Did he do it to make science in all seriousness sexy? Like sort of to get people sort of more excited? Today, no one really knows. I've seen it historically expressed as it was derisive or that it was spectacular, one or the other. But yes, the right answer is it's an expansion of space and time from something small to something big. It was not an explosion. And now we have this problem where we think, oh, if the big bang is an explosion, what did it explode into?

12:04you know, things like that. Well, a key part of that. Would it explode from? Yeah, there's a lot of other - And then there's this thing called, this is cosmic inflation, right? That's right. Which happened in the first tiny fraction of a second. Which is an expansion within an expansion. Right. Imagine if you're blowing up a balloon slowly, and then suddenly someone slaps you on the back and your air all goes out at once, and it blows up, and we call that inflation, which gets mixed in with all kinds of other things. Name during the Jimmy Carter era, hyperinflation that existed at the - Just before.

12:32Just before. Nixonian times. Are you sure? But there is a theory. I'm pretty sure, but it was like 10%. It was in the 70s. But there is a 10 % inflation. When this happened, okay, this cosmic inflation, there is a theory that a gas cloud formed the initials WIN, which is whip inflation now. Jimmy Carter. Come on, that was good. Okay. See how I brought that back? Come on. It's historical, though. Yeah. Right? By the way, just a quick, just while we're on the, how does it relate back to society? I came of age, I'm a little older than you. I came of age when people... I think I heard him whisper, you're old as dirt.

13:13I didn't think it was a very scientific term, but that's what he used. I think I'm 20 % older than Charles here, plus or minus. So I came of age when we applied computing power to what galaxies would do to each other when they encountered. Classic paper by two brothers, Alar and Yuri Tumray in 1972. Tumray and Tumray, yes. Terrific paper. What kind of data are you putting into the computer? So we saw these weird-looking galaxies out there. This is just an analog, so I don't want to spend too much time on it. Really weird-looking galaxies, and there was someone in our field who compiled them into one catalog.

13:51Chip Arp. Called the Atlas of... Peculiar galaxies. Yeah, these are galaxies. They're just weird. They don't match any form. So I don't know why, but here they are. And everyone's saying, what could make these galaxies? Are they born that way? And then Gerard de Vaucouleur, who was a galaxy. Jerry, I call him Jerry. Yeah. We're like this. He, he's very French. He. Very. He was pretty sure that a crashed Lexus is not a different kind of car. It's still a Lexus, okay? So he, that was his head on. It becomes a Toyota, actually. so he becomes a toyota good one good one so the idea that no they're not peculiar they changed because they had these encounters these collisions these galaxies collided yes and they're colliding all the time right okay now i forgot why i i was even going to mention this when was i going to non-inflation oh yeah yeah so at the time at the time this is now in the 80s okay these are your people now in the 80s we called this you'll understand why in 10 seconds come on so we called it in our field mergers and acquisitions we did are you serious yes i had no idea don't see mergers and acquisitions oh my god because that was so hot then it was so hot right out of wall street so we have inflation and mergers and acquisitions and now look where we are that's We were Dr.

15:19Stank.

15:35Hello, I'm Alexander Harvey, and I support StarTalk on Patreon. This is StarTalk with Dr. Neil deGrasse Tyson.

15:54The big bang within the bang, big bang at the tiny fraction of that moment when it happened. Yep. Is there still yet an explanation as to why that had happened? There are numerous competing hypotheses, but we don't have the experimental evidence to show the initial burst or the thing that caused it to happen. We're pretty sure it did happen. And we got close to that energy. The bigger is our particle accelerator, the earlier in time it can see, not see, but represent in the temperature density in the particle accelerator. You can say in the first microsecond or the first nanosecond of the universe, what was the temperature?

16:36Oh my gosh, it was this high. Have we ever reached that temperature in the lab? No, not yet. The day we do, we get to say, we think we have sampled what the early universe would have looked like. Do new particles pop in? Is there a dark matter particle that shows up? We don't know. But do you both understand there's brilliant scientists that lay people like myself are looking for, in all seriousness, solid answers, right? Like I'm still trying to figure myself out. Hang on a second. Trying to figure myself out through counseling, therapy, whatever. The universe hasn't been able to figure itself out in 13.8 billion years.

17:08Can you guys get on the stick? You gave us an answer? No, hold on. I would like to, I would like to, but this is the, you've hit the key point in the difference between - Thank you. Yes. You've hit the key point between what I think is the difference between scientific truth and non-scientific truth. With scientific truth, we always put in the, but maybe we're wrong part, that we don't know for absolute sure part. And that's really, really important, right? Science could not have progressed if somebody said, this is the right answer. And then everyone just, oh, okay, okay. Because people would have stopped exploring.

17:43It's incredibly important to recognize that we have ignorance. Neil has a terrific term for this, the perimeter of ignorance. We have to understand that there's a space beyond which we don't know the answer yet, or even what we think we know could be wrong because of this, this, this, this, and this. Which is why, Paul, you need to love the questions themselves in your search for answers. That is too profound. Dude. Too profound. No, that's Rainier Maria Rilke in a poem. Yes. Plus, I have to adjust what he just told you here. Like a chiropractor. He's going to— Adjust. Wrong word. I need a different word.

18:22He's going to straighten your mental back out. Your mental vertebrae. Yeah. So I put a lot of thought and energy into defining what true means, and I've settled in a way that I think is highly defensible and should be adopted. Okay? Okay. So a scientific truth is that which has been established by repeated observations and measurements. When that happens, it is not later shown to be false. So we can talk about it as an objective truth. Equals mc squared is not one day going to be found to be false. that Earth goes around the sun, that the sun is hot, that the sun undergoes thermonuclear fusion is not going to one day be found to be false.

19:11Where Charles is referring to, we have to have some acceptance that we could be wrong. Yes. About things that we are not definitively... Correct. On the frontier, we're wrong most of the time. But there are some... 90%, 90%. There are some things that we've reached. The community is comfortable saying, you're saying that there are some things equals MC squared, et cetera, where we're not questioning that anymore. The huge things, huge swaths. Otherwise you can't do - Otherwise we're not flying airplanes. Otherwise you can't do the exploration into the things that you don't know. Airplanes wouldn't fly.

19:43Rockets don't go to Mars and land exactly where we tell them. You could continue to research that there's another rationale, but I think what you're saying is - No, no, no, hold on. Let me finish. I'm almost done, okay? It doesn't mean that we will not one day find a deeper truth in which the experimentally verified truths are embedded. such was the case with newton's laws of gravity and motion those laws in the realms in which they were tested are still valid we went to the moon using newton's laws and not einstein okay there was no relativity in the apollo voyages it was all newton's laws of gravity and motion we then learned that at high speeds high gravity newton's laws break down holy shit do we discard Hard Newton?

20:31What's going on? Well, there's gravitational waves. So Einstein finds a deeper understanding of gravity and motion. And he gets his theories of relativity, the special theory in general relativity. Guess what? When you plug low speeds and low gravity into Einstein's equations, they become Newton's equations. People say, oh, we've Newton out, Einstein in. That misrepresents what's actually happening here. Well, it's chicken and egg. You can't have one without the other. Well, no, I mean, in terms of the pathways of discovery, you get the restricted case before you discover the general case. My only point is the uncertainty that a scientist brings to the frontier is in the realm of things that we have not yet experimentally verified.

21:15And it's completely uncertain at that level. And we're just duking it out at conferences and the like. And the press eavesdrops on the conferences. They say, oh, the scientists don't know what they're talking about. And the people say, I don't trust science. Yeah. As they're on their smartphone talking to someone a thousand miles away. I don't trust science, you know? So I just want to clarify that. And two other truths. There's your personal truth. Like, is Jesus your savior? Is Muhammad your last prophet? Is Beyonce your queen rather than Taylor Swift? So that's a personal truth. And then you have political truths, which are things that become true in your head simply because they were repeated so often.

21:53Yes. Which are the foundations of— Or because you read it on Twitter. Yeah. No, it's how many times you read it. It's how many times. And so - But is that any different - Those are foundations of propaganda. But is that any different than commercial advertising? No, exactly the same thing. You're going to show you this Toyota 50 times, and by the end of the week, you're going to be like, I got to get a Toyota. That's a great car. And no matter what they're telling you, that becomes true. So those are the three truths. Right. And I will never speak of an absolute truth because that's not what science does.

22:20Newton's gravity was proven to be wrong is true. it was wrong because in certain conditions in the universe, it was not correct. But that's an eye-opening moment. But those are extreme conditions well beyond the experimental realm. But that expands our mouth. It's a good thing. When a bad thing happened like that, it's a good thing because it expands our base of mouth. And you don't call it bad. You don't invest emotions in it. Some people do, but it's not good if you do. Well, I talk like a six-year-old. No, so do I. Well, this is perfect because this next question is about gravitational waves.

22:56Love it. I'm telling you, this is eerie. Okay. This is Mitchell Ransom. Mitch from the UK. I would love to know more about what we can learn from gravitational waves. It's cool. We can detect them, but what can that do for our understanding of the universe? Marvelous question. Perfect second. Marvelous question. You take this out back clean up on it. Okay, go. I will be the one so to you. And then I'll be the guy who shouldn't steal second and doesn't, gets thrown out and ruins the inning. Well, if Otani were stealing, he'd actually make it. Oh my God, yeah. Or if you're gonna steal second, do it deep into the count of a batter you wanna see come up again in the next inning.

23:40Yes, also the, that's true. Right, because they get fresh. Right, and also the - This is fundamental baseball, which doesn't get talked about nearly as much as it should. Small ball. We should do a whole thing on baseball. Oh my God, yeah. Oh my gosh. We could all geek out. I think the pitch clock, while it's helped speed the game up, I mean, stealing is so much more interesting and fun to watch because you go over there twice, you know you're gonna get, you can't go back at third time. That's right. They're very interesting. Rules are always fun too, talking about rules. It's the most interesting sport to watch, I think, baseball because of all of the machinations.

24:13But anyway. Yeah, okay. Well, here's the deal. Gravitational waves are essentially to the universe and space and time. as say ripples are in a pond, right? So if you see ripples going on in a pond or any body of water, you can deduce things about that pond. What is the water made out of? Is there duckweed on the top? How deep is it? Is there ice? You know, things like that. All the different things about that puddle. By the way, the depth is, affects the amplitude of the ripple. Completely, right. So it's why when you're at the beach, How come, you know, you see a swell sort of out there, but then it gets closer to the shore, it becomes a big wave.

24:57So the energy that is out there in the ocean, which is shared vertically to the bottom of the thing, as you get shallower and shallower, that energy has to manifest somehow, and the height of the wave grows. And so the energy is the same, but the height and how you experience it as a beachgoer. But where does wind come into this? Because wind can create a ripple. The wind can also create a ripple. That's right. The top has an effect, the bottom has an effect, and the side has an effect, right? Where is it coming from? In other words, it's bouncing off the sides of a wave. The edges make a difference if you're in a bay or if you're just hitting a wide shoreline.