Pod Insights StarTalk Podcast Cosmic Queries – The Atlas of Peculiar Galaxies with Charles Liu About this episode How can we use AI to explore the universe? Neil deGrasse Tyson and co-hosts Chuck Nice and Gary O’Reilly answer grab-bag questions about simulations, black holes, warp drive and more with astrophysicist and “Geek-in Chief” Charles Liu.
Transcript Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
0:01 Neil deGrasse Tyson? Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk Sports Edition. And this time, we're doing a Cosmic Queries Grab Bag. Got with me Chuck O'Reilly.
0:25 Chuck Nice? Wow, you just married us. You married us and somehow I had to take Gary's name. What does that say? What is going on here?
0:36 Neil deGrasse Tyson? Gary O'Reilly. I think of you as my one common conjoined co-host. I'm sorry. So Chuck Nice.
0:44 Chuck Nice? Good to be here.
0:48 Neil deGrasse Tyson? All right. Gary O'Reilly, former footballer from the UK and broadcaster.
0:55 Chuck Nice? Yes, I know.
0:55 Neil deGrasse Tyson? And we had a little piece of him for us. Very good to have you. This is a grab bag. And anytime we have a grab bag, this is like the bat signal going up into the clouds. We got to reach for our geek in chief. The one, the only. Hold your applause till the end. Charles Liu. Hey. Okay. Hey Neil, hey Chuck, hey Gary. So good to see you guys. A friend and colleague, astrophysicist Charles Liu, who's a professor of astronomy and physics at the City University of New York in Staten Island. And always good to have you here. You're a fan favorite. And so you're going to help us in this grab bag.
1:36 Neil deGrasse Tyson? I mean, I might be able to do some, but when it comes to really geeky answers to cool questions, I am unworthy. And I will just sit back while you take the mic. But I'm happy to be here. It's always fun and the questions are always the best. They're always cool. They're always cool. So Gary, Chuck, you got questions lined up?
1:58 Gary O'Reilly? Yes. Right, let's start with one of our very favorites. And I can't do The Voice anywhere near. The abilities that Chuck has, but it's Alejandro Reynoso.
2:10 Neil deGrasse Tyson? No, no, no, give it to Chuck. Why are you reading that? Chuck?
2:12 Chuck Nice? Oh, I didn't know we were starting here, so I, I, I gotta, I gotta go pull up, I gotta pull up Alejandro.
2:21 Neil deGrasse Tyson? Pull up the message. So again, all of our, all of our cosmic queries today are exclusively asked by Patreon members with our new entry level category of $5 a month. So you can't argue with that.
2:34 Chuck Nice? All right, here we go. Let's start it off with our friend Alejandro Reynoso, who comes to us from Monterrey, Mexico. And he says, hello. Or should I say, hola?
2:53 Chuck Nice? My question is, how do you think we can use artificial intelligence in exploring the universe?
3:02 Neil deGrasse Tyson? So there it is. So, so Charles Lu, what do you have to say about AI and our field?
3:07 Charles Liu? Alejandro, let me tell you, you are right on the mark. And in fact, we are already trying to do precisely this. As many of you know, I am part of the Cosmos Collaboration, working with the James Webb Space Telescope. Neil, you're familiar with that. Yeah, back when we were working on it with just the Hubble Space Telescope data, right? But now we have a James Webb Space Telescope.
3:30 Neil deGrasse Tyson? Just to be clear, the Cosmos Collaboration is a consortium of people and institutions that have targeted sections of the sky and others just to hammer it with as many kinds of telescopic observations and detectors as possible to learn basically everything knowable about sections of the sky that we target. So continue. So now we've applied this to the James Webb. So what do you have going?
3:54 Charles Liu? Well, the James Webb Space Telescope's first seasons, most significant observing project is to use the James Webb to aim at the cosmos field, which you described so aptly just a few seconds ago. And so we are spending 270 hours of James Webb time in just a small patch of sky about the size of your pinky fingernail.
4:19 Neil deGrasse Tyson? At, at arm's length. Yeah.
4:21 Charles Liu? At arm's length. That's right.
4:22 Chuck Nice? When you're looking up at the sky. Right.
4:26 Neil deGrasse Tyson? Yes, yeah, your pinky at arm's length. Not finger in your eyeball. Right. I'll do that. All right, good.
4:32 Charles Liu? Yeah, that would be difficult. So, so there's literally terabytes and terabytes worth of data coming from all the different observatories around the world. And James Webb is just layering on that next layer of information about this patch of sky. And no human being can individually process all of that information in any meaningful way. So what we need instead is the opportunity to use machines, machine learning, deep learning, artificial intelligence, to help us make sense of all of this incredible amount of information. So, for example, we have information about possibly 2 million or so galaxies
5:15 Charles Liu? within this cosmos field, ranging all the way out to 13 and a half billion light years away.
5:21 Neil deGrasse Tyson? Just to be clear, this fingernail at arm's length blots out 2 million galaxies on the sky to the edge of the universe.
5:30 Charles Liu? Each of these 2 million galaxies has thousands of pieces of information about it that have been gathered by all these telescopes that have been trained on it for the past 20 years, off and on. And now we've added James Webb on top. Can we make a pattern? Can we understand what actually matters? Can we ask ourselves, can we look at all 2 million of these galaxies and find something new? Actually, probably not. But using artificial intelligence, we can do that. We can say, here are the parameters of what we think are normal. Can you please find for us all the normal things? And then all the abnormal things? And then tell us what is normal and what is abnormal? Or what should we be looking? Right. And what should we be looking at
6:15 Charles Liu? that allows us to sort of understand the change of the? Galaxies in the universe from 13 billion years ago to the present day. I mean, that's a heady question, which any individual human can sort of grab the most creative and interesting ways, but processing all of that information, AI is the answer. We're not there yet.
6:37 Neil deGrasse Tyson? So Charles, why isn't this just more powerful computing rather than what people generally today think of as AI? Because we've always wanted, we've always needed computers ever since computers have been brought to our field to, we've needed it to reduce and analyze massive amounts of data, even when massive amounts of data in the day was only a kilobyte or, you know, or a megabyte. And so now we're up to terabytes. So isn't it just more powerful computing? Number crunching? Yeah. As opposed to thinking? Right, yeah, is it really thinking?
7:12 Charles Liu? Number crunching has been going up. It actually is extremely important, and you're right. That's most of what computers are doing for us in astronomy today. But it's that next step, I think it started maybe three or four years ago, that we really started shifting over toward machine learning and artificial intelligence. So both are still working hand in hand together. And, you know, in the current circumstance, the AI part is still in its infancy. A lot of times when people publish scientific results that they found using AI or machine learning, they're probably not right. But we publish them anyway because we say, hey, it might be right.
7:57 Charles Liu? Please let us let the rest of us colleagues go back and check to see if what this machine found is actually something in reality.
8:03 Neil deGrasse Tyson? The all-important verification step.
8:05 Charles Liu? That's right.
8:06 Neil deGrasse Tyson? Right, and so compare all of that to neural nets.
8:11 Charles Liu? Well, neural net is just another way that we can abstractly map the idea of intelligence and pattern recognition, right?
8:22 Neil deGrasse Tyson? Right.
8:22 Charles Liu? Current.
8:23 Neil deGrasse Tyson? Because we think that's how brain works, that's why we say neural, right?
8:25 Charles Liu? That's right.
8:25 Neil deGrasse Tyson? It's just the connectivity to find patterns and whatever it is that might manifest.
8:31 Charles Liu? That's right. The neural net itself is a pretty complicated thing, but we can strip it down to very basic components and say, can you do a one dimensional or two dimensional or three dimensional discussion about all this information, try to make connections that we otherwise wouldn't be able to see if we were just trying to use one CPU by itself, you know, one brain or one processing unit. The neural nets in our brains are not just three dimensional, they're four, five, six, 10, you know, each neuron attaches in many unusual ways to many others. So there's a sort of an emergence of awareness that comes about from you have these networks of that kind of complexity.
9:14 Charles Liu? So these are the things, I think you did a Cosmos episode on this, right, Neil, once?
9:19 Neil deGrasse Tyson? Yeah, we did, yeah.
9:20 Charles Liu? About how intelligence and the concept of a very complicated neural net like a human brain can actually be more complicated than even an entire galaxy worth of stars and their interactions and so forth. It's very, very powerful, but poorly understood.
9:37 Neil deGrasse Tyson? All right.
9:38 Gary O'Reilly? Are we looking for the right things? I mean, using AI obviously should be an advantage, but are we looking for the right? Because there must be things out there we don't know exist, but we should be looking for, but we don't know to look for them. Is AI going to be able to assist in us in that kind of capture of data?
9:55 Neil deGrasse Tyson? In other words, can it discover what it's not looking for?
9:57 Charles Liu? Right.
9:58 Gary O'Reilly? Thank you.
9:58 Charles Liu? It can, it can discover what it's not looking for. That's a great question. It can discover what it's not looking for if we tell it to look for things that it's not looking for. Right. So in a sense, you're number crunching, right? Data reduction or, let's say, computational work, that will give you the answers to things that you are looking for. Now you tell a machine and say, "These are what we are looking for. Can you tell us any exceptions to what we found?"
10:23 Chuck Nice? So, anything, it would have to be something anomalous, but wouldn't you have to program the parameters of what an anomaly is in order for-
10:31 Neil deGrasse Tyson? No, no. You only have to know what we're familiar with and anything-
10:34 Chuck Nice? Well, anything else would be an anomaly.
10:36 Neil deGrasse Tyson? That doesn't fit in that box, would be an anomaly.
10:38 Chuck Nice? That is an anomaly. So, okay, so that means, well, that is kind of like-
10:41 Neil deGrasse Tyson? That's the easiest part of the, that's the easiest part of the job. If it doesn't fit, stick it in a box.
10:46 Chuck Nice? If it doesn't fit, it goes, "Oh, that's odd. Okay, now let's look at that. Okay."
10:49 Neil deGrasse Tyson? In fact, 60 years ago, one of our colleagues did that. He looked at all these beautiful galaxies in the night sky. There was a beautiful spiral and a beautiful elliptical-shaped galaxy. Who ordered this one, which was tangled and mangled, and he made a catalog of just the tangled, mangled-looking galaxies. And it was called the Atlas of Peculiar Galaxies. And it was just, it was the catch basin of nothing that fit anything else. And, Charles, you remember, it became one of the most studied catalogs in the canon of cosmology.
11:22 Charles Liu? Alton C. Arp. Chip Arp's Atlas of Peculiar Galaxies, published in 1966. Yes, tremendously interesting. And what it was, was it turned out that Chip Arp's ideas of why they looked peculiar were incorrect. But by putting them together into a catalog, people could look at them and start wondering and thinking about what actually was going on. And it helped us understand that galaxies collide, that they crash into each other, and they create amazing structures which we could not have imagined had they not collided. And that led to the entire field of computational astrophysics as applied to galaxies.
11:59 Neil deGrasse Tyson? And by the way, and we needed, we needed the computers to make that happen. So that was, in the 1970s, computing power rose to then say, "Well, I wonder what a galaxy would look like if it collided with another galaxy. Hey, that matches Arp's catalog number 32.3." And, and then you, and then you look at it at a different angle, that's a different object in the catalog. And so all of a sudden, we would, we ought to explain all the galaxies just as witnesses to train wrecks.
12:26 Chuck Nice? You guys keep saying collide. When you say galaxies collide, is it that the galaxies-
12:33 Chuck Nice? Gravity affects another galaxy's gravity? Or are you looking at actual objects hitting one another? Because aren't galaxies so spread out? What is it? What's an actual collision?
12:45 Neil deGrasse Tyson? Chuck on the case. Hmm.
12:47 Charles Liu? Beautiful, beautiful question. When galaxies collide. When galaxies collide.
12:52 Neil deGrasse Tyson? That's a movie title right there. We need that one.
12:55 Charles Liu? They, uh, they do. The stars are so far apart that they almost never hit each other directly. So it's like swarms of bees or hornets, you know, nests, wings, rats through one another and affecting one another from a distance. But a collision doesn't have to happen only when a physical object hits another physical object. What you said, the gravitational effects of one object affecting the other is indeed as much of a collision as we might think of, say, two vehicles hitting one another or something. And so instead, you get these twists and turns, you get bends, you get loops and whirls, and it is all gravitational. Yes, indeed. So it's really.
13:39 Neil deGrasse Tyson? So we count a gravitational encounter as a collision because they affect each other. But I, I've quantified this bee analogy. So if there were four bumblebees flying randomly across the continental United States, the chances of them accidentally bumping into one another is the same as two stars colliding in a, in a, in two galaxies. So yeah, basically two stars are not going to physically collide, but they'll all feel each other's gravity, and that's enough to make a train wreck. So.
14:10 Charles Liu? And a beautiful train wreck they can be. These kinds of train wrecks cause the formation of new stars, new planets, sometimes in the billions at a time. They feed supermassive black holes, they create quasars and active nuclei. They're one of the most important engines of the evolution of the universe itself.
14:29 Neil deGrasse Tyson? Wow. The engine of the evolution. We gotta take a quick break. When we come back, more cosmic queries grab bag. We'll be right back.
14:53 Neil deGrasse Tyson? We're back, StarTalk Sports Edition. Cosmic Queries Grab Bag with our geek in chief, Charles Lu. All right, and of course Chuck and Gary. So give me some more questions, we're on a roll here.
15:05 Gary O'Reilly? Okay, this one I think is pretty topical. So this is from Samuel Fairchild, greetings from San Antonio, Texas. What can we learn from the runaway supermassive black hole that was spotted by the Hubble telescope, trailing a 200,000 light year long tale of new star formations? Answers please.
15:28 Charles Liu? It is most likely a classic example of what happens when galaxies collide.
15:35 Neil deGrasse Tyson? When galaxies collide.
15:37 Charles Liu? Lots of things can happen.
15:39 Gary O'Reilly? In a galaxy far, far away?
15:41 Charles Liu? They could be far away. We hope they're far away, but they could be close by. Remember, in a few billion years, the Andromeda Galaxy will collide with the Milky Way. Then we'll have a close up view of what happens.
15:50 Neil deGrasse Tyson? When galaxies collide.
15:54 Charles Liu? So the story is this, right? You have a galaxy, and it's about 100,000 light years across. Here comes another galaxy that's also 100,000 light years across. They hit each other at just the right angle, and you can pull a trail of gas outward, a couple hundred thousand light years long. When that happens, you're basically creating a stream of new stars forming all along this trail. And so there's your 200,000 light years long trail of new stars forming. Meanwhile, part of that collision could have hit. And you know, there are many different ways galaxies can collide, but perhaps in just the right angle and at just the right speed, the supermassive black hole in one of those galaxies.
16:42 Charles Liu? Got stripped out of the body of the galaxies that are colliding. So whereas the rest of the galaxies' material is sort of coalescing into a single blob, that supermassive black hole is out on a trajectory that looks like it's following that gas going outward. There's a lot of possibilities, and we've only just begun to figure out what's going on.
17:04 Neil deGrasse Tyson? And by the way, the gas, unlike the stars, the gas doesn't really pass through itself. When the gas collides, it'll, it's like two hot marshmallows sticking. So a lot of interesting things can happen in the gas part of the colliding galaxies, separate from the stars.
17:19 Charles Liu? Right. You can often think of the gas in a galaxy like the water in a swimming pool or something. They, they have a dissipative force. They are viscous, even though they're very sparse by Earth standards. They wind up out in space, sort of along the millions of years type time scales and the millions of light years type size scales, acting very similarly to what you might expect.
17:43 Neil deGrasse Tyson? So Charles, I did an episode of Nova Science Now once where it was exactly that reference. I was at a swimming pool and I, I had a, I had a bucket, if I remember this correctly, I think I had a bucket of ping pong balls and so did someone else. And we tossed them towards each other and only a few of the ping pong balls hit, would hit each other. But then we had buckets of water and we threw the buckets of water at each other and the water just, it was there, as you said, it's dissipative. And we did it slow mo and you can see it, it was pretty cool. All right, keep going. What else you got?
18:14 Gary O'Reilly? All right. Next question up is from Mo, M O E. Aloha Neil and Chuck. What evidence can you provide to show that we aren't in a simulation?
18:27 Charles Liu? Aren't?
18:28 Gary O'Reilly? Are not.
18:29 Charles Liu? Ooh.
18:29 Chuck Nice? Oh, interesting. Proving the negative. Can you prove the negative?
18:35 Neil deGrasse Tyson? Oh, okay. I, I have an attempt at it, but go on, I want to hear what, what my geek in chief has to say.
18:41 Charles Liu? Rene Descartes, hundreds of years ago, right? The guy who, you know, after whom we've named the Cartesian coordinate plane, but also a great philosopher, rationalist at this time.
18:51 Neil deGrasse Tyson? Right. I think therefore I am.
18:53 Chuck Nice? I am.
18:54 Charles Liu? Yes. Yes. That's right. And he basically set out the idea that if there were a simulation that was good enough, we would not be able to tell. There's just no philosophical way to tell as long as the simulation is good enough. So the only evidence that we can give that we are in a simulation is if somehow we see a glitch. You may remember the movie Inception. Uh, when the people in the dreams were trying to figure out whether or not they were in a reality or not in a reality. And one particular person figured out that he was in a dream because the texture of the carpet was different from what he remembered in reality. Right?
19:39 Charles Liu? So every single piece of evidence out in the universe has to be consistent with what we think is real. Right? And if not, if there's a glitch, then we're in a simulation. We can also go to The Matrix and talk about that.
19:56 Chuck Nice? Okay.
19:57 Charles Liu? And how the reason they were able to know they were in a simulation was because something just didn't happen correctly. That's the only way, according to Descartes, that we can prove that we are in a simulation. But how can we prove we're not in one? You just have to keep looking for the glitches.
20:15 Chuck Nice? Oh, wow. Look at that.
20:17 Neil deGrasse Tyson? Wait, wait. So if, if we don't find any glitches, we're either not in a simulation or it's a perfect simulation. And therefore, what's the point of even distinguishing the two?
20:25 Chuck Nice? Well, then, okay. So with that, with that lineup with paranormal activities counting as a glitch. Ooh. So paranormal activities are not, you know, following the laws of nature, physics or what have you, with that count as a glitch. Listen, Chuck. That would say that we are. So what are, what are we calling a glitch? Or, or what's definition? Yeah. Or.
20:57 Neil deGrasse Tyson? A miracle. A miracle or something that happens outside of the laws of physics.
21:02 Charles Liu? Miracles and paranormal activity at this point in our understanding of the universe are only things that we don't understand yet. There's nothing that's been shown to be conclusively a violation of the laws of physics. Just something that we haven't explained the rest of physics yet.
21:23 Neil deGrasse Tyson? Wait, wait, wait. Jesus walking on water violates a ton of, a ton of laws of physics right there.
21:29 Charles Liu? If that actually happened.
21:32 Chuck Nice? Well, he, now, now, in all, in all, in all defense, he has some really good sandals. Okay.
21:40 Neil deGrasse Tyson? Yeah, Jesus sandals.
21:43 Chuck Nice? He had Jesus sandals now.
21:45 Neil deGrasse Tyson? Jesus sandals.
21:46 Charles Liu? So, so we all have to think about these questions as skeptically and as optimistically as we can at the same time.
21:56 Neil deGrasse Tyson? Okay, I gotta add another, another pop culture reference. My single favorite episode of the two and a half seasons or whatever it was of Black Mirror was the episode titled Hang the DJ, which has nothing to do with the entire story. It's the name of the song that you hear at the end. In that, it's a dating community. You go, you date multiple people to see who, when you like, and then at the end you get married to them. And we learn, should I give it away? I have to give it away, otherwise I can't talk about it. We learned that all the people in this story are being simulated. But you don't know this because you're with them and they're testing, they're dating, and oh, that didn't work out.
22:40 Neil deGrasse Tyson? Let's date another, I gotta stay three months with this person. It's all prescribed and it's all do it and they hate each other or they love each other, whatever. And one of the people, one of the women who likes skipping rocks, skipped rocks and said, you know, every time I skip rock, it only skips three times. And she said.
22:59 Charles Liu? Oh, so she figured out the glitch.
23:01 Neil deGrasse Tyson? Some should skip one and some should skip four.
23:03 Charles Liu? Hmm.
23:03 Neil deGrasse Tyson? She just, she just tossed it up and you don't even know to pay attention to that. While, when that's happening. All right. These are characters that have their own sense of free will. And one of them noticed that every time she skipped rock, it was exactly and identically three times. And we later learned that all of these people are a simulation so that when at the end you emerge and the two people, they escape the, the simulator, they escape this place. And as they escape, you see the digitization of things happening. And the next scene are two people meeting up in a bar who were matched by that simulation. It was like, holy shit.
23:43 Charles Liu? It's, it's, it's the ultimate swipe left or swipe.
23:47 Neil deGrasse Tyson? Oh, my gosh.
23:49 Gary O'Reilly? Yeah.
23:50 Neil deGrasse Tyson? So the simulation tested everybody's compatibilities. And it was like, oh my, but in it was that one observation. So ever since then, and a little bit before then, I've been checking for things that maybe should have different kind of variation than what should. That's interesting about the carpet though, Charles.
24:06 Gary O'Reilly? But do we, do we then project our desire to find a glitch into our thinking and observations?
24:15 Charles Liu? Without question, Gary, that's a great point.
24:17 Neil deGrasse Tyson? So it creates a bias.
24:18 Charles Liu? We humans are biased in one direction or another in general. Right?
24:23 Neil deGrasse Tyson? Yeah.
24:23 Charles Liu? And, and just like it's very hard for all of us to be rational all the time, and maybe we shouldn't be, uh, the circumstance is of our detecting whether we're in a simulation or not are almost secondary in importance to whether or not we are in whatever environment we are, real or simulated, and live the way we want to live and do the things we want to do.
24:46 Neil deGrasse Tyson? So in my recent book, Story Messenger, I, I reflect on what a simulated world would be, and I use that as evidence that we're not in a simulated world. You know what it is? A simulated world is created by computers and computers are absolutely logical. And so.
25:07 Neil deGrasse Tyson? No set of computers would ever create the world we live in.
25:14 Neil deGrasse Tyson? So it's the inanity defense. It's like Earth is inane in every way. Computers have higher integrity than that, even in a simulation. That's my evidence.
25:24 Charles Liu? That's great evidence, except that you may be putting too much stock in our inanity. It may well be that inanity is an inherent part of logical systems.
25:34 Neil deGrasse Tyson? Ah, no, I'm not going, I, yeah.
25:38 Gary O'Reilly? Okay, Neil, would, would a computer, would a computer be able to generate or recreate love?
25:45 Neil deGrasse Tyson? Oh, yeah, I don't see why not.
25:48 Gary O'Reilly? You sure?
25:48 Neil deGrasse Tyson? I don't see why not.
25:49 Charles Liu? Depends on what you think love is.
25:50 Neil deGrasse Tyson? Well, no, I got this, I got that, this is, I'm past that, okay? So, so, so watch, so watch. You, you get everybody who's in love with something or some other person, right? And then you do a brain scan. And I'm making this up, but it's plausible. You do a brain scan and everyone has the same part of their brain lit up while they have these feelings of love.
26:09 Charles Liu? Right.
26:09 Neil deGrasse Tyson? Then you take someone who doesn't have those areas of their brain lit up and show them something that's completely neutral. Right? Like a book, just a, a book cover or something. Then you light up that part of their brain and see if they fall in love with the book. And if they do, we know exactly what love is, is the neuro synaptic of this section of the brain. There it is, and we can create it for you if you want it. If two people are, are in long marriage and they're falling out of love, go back and re-stimulate their back in love if they're like newlyweds.
26:38 Chuck Nice? I mean, clearly, clearly, love is a neurochemical synaptic function of the brain. I mean, it just, it just has to be on a biological level. Otherwise, you know, I mean, you can attach ethereal qualities to it, yes. But, I mean, people who, if you don't have, if you are brain dead, you can't be in love. Period.
27:01 Neil deGrasse Tyson? Right, in fact, you don't have to be fully brain dead, you can be partly brain dead in the section that would matter in that category.
27:07 Charles Liu? But sometimes it makes no sense.
27:08 Chuck Nice? No, no, wait, as a matter of fact, we have people who are incapable of love. Okay? We call them sociopaths.
27:18 Neil deGrasse Tyson? Yes. Or, or they're incapable of, of empathy.
27:21 Chuck Nice? Capable of empathy, but you have to have empathy to have love.
27:24 Charles Liu? So imagine, imagine a person.
27:27 Chuck Nice? All right.
27:28 Charles Liu? Who does not, imagine a person that is somehow.
27:33 Charles Liu? Perhaps what we might call defective and unable to experience empathy or love. This person carefully studies thousands of people who are happily in love, figures out all the behaviors that are observable from an outside person of how to be a person who expresses and shows love. And then just mimics all those behaviors beautifully. Running into a person or choosing a person to treat that person that way, to work with that person that way, to do the things with that person that all those other people in love are behaving. Is that person exhibiting love to another person?
28:14 Chuck Nice? No, you can't tell.
28:16 Neil deGrasse Tyson? That's why we go inside your brain with the brain scan.
28:20 Chuck Nice? That's what a brain scan is for.
28:22 Neil deGrasse Tyson? That's the whole point of the brain scan.
28:23 Charles Liu? If you don't have that part of the brain lit up, but you behave as if that part of the brain were lit up, are you still behaving with love?
28:31 Chuck Nice? So I'm gonna say from a utilitarian standpoint, no, you are not. Because the only reason you would do that is because somehow you are being served. Otherwise, you would not be a sociopath. You would actually be exhibiting love itself.
28:43 Charles Liu? Perhaps your definition of behaving in a way that's self-serving is to behave in a way that everybody else in the world looks to you as if you are in love. But then are you? You may not be, from your brain's point of view.
28:58 Neil deGrasse Tyson? That's why I introduce science here, where you go inside the brain. It's the whole point of that.
29:04 Charles Liu? I'm asking you a different kind of science. From the observable perspective, assuming no hidden variables, okay? Assuming that the interior of the brain is unknowable.
29:16 Neil deGrasse Tyson? I'm not gonna, I'm not have to assume something that's not true.
29:18 Charles Liu? But quantum, but quantum mechanics, for example, suggests that indeed there are things about particles at certain levels which are not observable.
29:28 Neil deGrasse Tyson? I agree, but we're talking about your brain and not a particle.
29:31 Charles Liu? Can your brain behave in that way? If the brain were considered not something that you can poke and prod, what if love, in fact, does not light up the same part of your brain?
29:43 Neil deGrasse Tyson? All right, when we come back, more Startalk Sports Edition, Cosmic Queries with our geek in chief, Charles Lu. We'll be right back.
30:03 Neil deGrasse Tyson? We're back, StarTalk Sports Edition, Cosmic Queries Grab Bag, with our geek in chief, Charles Liu. Charles, how do we find you on the internet?
30:11 Charles Liu? Oh, well, uh, @chuckliu, C-H-U-C-K-L-I-U, on Twitter, and @theLuniverse, T-H-E-L-I-U-N-I-V-E-R-S-E, on a wide variety of platforms.
30:26 Neil deGrasse Tyson? The Luniverse?
30:28 Charles Liu? Yeah. Podcast is going, wherever you get your podcasts. We have lots of conversation and fun with that, yeah.
30:34 Neil deGrasse Tyson? All right, cool, cool. And Chuck Nice, you're still Chuck Nice Comic? Everywhere, sir, thank you. Everywhere, cool, cool. Gary, are you still Three Left Feet?
30:42 Gary O'Reilly? Yes, I am, on Twitter.
30:44 Neil deGrasse Tyson? On Twitter, all right.
30:45 Gary O'Reilly? My Three Left Feet, or words.
30:47 Neil deGrasse Tyson? My Three Left Feet, got it, sorry. Sorry. So, uh, we got more questions here, bring it on.
30:52 Gary O'Reilly? We have, right. Matt Berg says, "Hello from Sheboygan Falls", I believe that's Wisconsin. Sheboygan! You're welcome. "I have used many of your discussions in my classroom to have my middle school students think a bit deeper about things." Teacher in the house! All right. "Is there a simple..." So, here we go, pay attention. "Is this..." It's uncomfortable, sit up straight. Uh, "Is there a simple way to ex..." Well, I'd start now. "Is there a simple way to explain to students what our universe is expanding into? In other words, if the Big Bang Theory created everything in our universe, does that mean that there has to be something outside of our universe? Or how can there be a nothing that is being expanded into?"
31:37 Gary O'Reilly? At this moment, this gentleman, Matt Berg, his mind starts to hurt.
31:41 Neil deGrasse Tyson? Ooh, that's not so bad. There's nothing wrong with the head hurt, yeah.
31:46 Charles Liu? Have you know that a friend of mine, who is a doctor, graduated from Ivy League School in Stanford and stuff, asked me that very same question not that long ago. So, you are in good company, Mr. Berg.
32:01 Charles Liu? Here's my way of explaining it. You are at the center of the universe right now. When we make measurements and try to figure out where the center of the universe was that it was expanding out of, it always goes to you. Whoever is observing observes that they are the center of the universe. So in other words, we are part of the Big Bang. When the universe was microscopically tiny, that is what has become us today. There's no central point because we are at the center. The center just happens to have gotten really, really big. That's one way of thinking about where the center of the universe is. You are the center of the universe.
32:44 Charles Liu? I'm sure your mom told you that at one time or another, or you thought that you were that at one time or another.
32:48 Neil deGrasse Tyson? I loved, I loved when you told you that.
32:50 Charles Liu? That's right. In fact.
32:52 Neil deGrasse Tyson? So what are we expanding into? Because that's what it started.
32:55 Charles Liu? The expansion into, you can think of as a different dimension. You can think of it as, say, space being three-dimensional, length, width, and height, expanding into a fourth dimension, which is not.
33:14 Neil deGrasse Tyson? What's space dimension?
33:15 Charles Liu? Yes, a fourth dimension of space, which is not length, width, or height. Or you can actually think of it as a four-dimensional spacetime where the expansion direction is in time, Neil. Where t equals zero, at time zero was the Big Bang, the universe was very small. And now time has gone on, t is about 13.8 billion years, and now the universe has expanded in that fourth dimension of time. You can find lots of different ways of thinking about it that are mathematically equivalent. So maybe if you're not like exactly getting the way that I'm describing it, maybe the way that you foresee it, or think about it, or envision it, is just as mathematically valid as the way that I'm talking about it right now.
33:57 Chuck Nice? Wow, that's a, that was elegant, Charles. I gotta give it to you. That was.
34:03 Charles Liu? I can't take credit for that.
34:04 Neil deGrasse Tyson? That was really cool, man.
34:05 Charles Liu? Well, thank you, Chuck. But, you know, remember, I didn't come up with this, right? Our scientific forebears, you know, have been working on this for a long time. And when they first came up with these ideas, they were hard pressed to explain them and understand them because they're so different from what we thought about when we were in those times.
34:26 Neil deGrasse Tyson? I'd like to add to it that you can have a multiverse where everybody's expanding, but if you're embedded in a higher dimension, then you will not necessarily collide, even if you can go to infinity. So if you take a sheet of paper and send it to infinity in every directions, so it's an infinitely large sheet of paper, now I can take another sheet of paper, lift it off of that into a higher dimension, a third dimension.
34:51 Charles Liu? Right.
34:51 Neil deGrasse Tyson? All right? Now it's just, quote, "parallel" to the other one. That can go to infinity and never intersect the other sheet. And I could do that into infinity. To infinity.
35:01 Charles Liu? And beyond.
35:02 Neil deGrasse Tyson? And beyond, yeah.
35:05 Neil deGrasse Tyson? So, if you embed our three dimensions into a higher dimension, you can expand higher dimensions and then they'll never collide if they're all in a dimension yet higher than themselves.
35:15 Charles Liu? Interesting.
35:15 Neil deGrasse Tyson? So there you have it. That's amazing. That's amazing. All right, another question. Let's keep them rolling, we're on a roll. So what else we got? Is it Gary or Chuck? Who's got the next question? Uh, Gary.
35:23 Gary O'Reilly? Okay, you want another one, just like the other one.
35:27 Neil deGrasse Tyson? Bring it on.
35:28 Gary O'Reilly? All right, Kartik. Kartik is from Germany. If the Earth's magnetic field is caused by the iron inner core rotating within the magma outer core, how does gas giant planets like Jupiter also have a magnetic field? Do we know anything about the composition of the interior of the gas giants?
35:49 Charles Liu? Hmm, we do. And the answer, we think, at this moment is that far enough down in a gas giant like Jupiter, the hydrogen, which we think of as a gas, turns into a metal. It becomes what we call metallic hydrogen. And so you have a core of metal of conducting stuff that can swirl, just like the core of metal in the Earth. And that's how you can get a magnetic field.
36:23 Neil deGrasse Tyson? Just to be clear, we didn't pull this out of our ass. If you remember your periodic table of elements.
36:30 Neil deGrasse Tyson? The, if you remember your periodic table of elements, hydrogen is, if it's a full fleshed out table, hydrogen appears twice, once in the upper left and once in the upper right. Once in the upper left is hanging out with the metals, and in the upper right is hanging out with the gases. And if I'm remembering that correctly, Charles, is that right?
36:49 Charles Liu? It can be written that way, yes.
36:50 Neil deGrasse Tyson? Written that way. And I said, well, why is it twice? And somebody said, well, sometimes it's metallic. I said, it's a fricking gas. What the hell are you talking about? Later, I would learn, under pressure, behaves just like a metal does, just like iron. And so, yeah, so it doesn't have an iron core, but it's got a metallic hydrogen core under all that pressure, for sure. And, and there it is, running a, running a dynamo on Jupiter, a rather ferocious one at that.
37:13 Charles Liu? Sweet. Look at that. That was good.
37:17 Neil deGrasse Tyson? We got one more in there. Quick one. Let's get a quick one.
37:20 Gary O'Reilly? A quick one. Okey dokey. Uh, let's see. Pim Bilek.
37:27 Gary O'Reilly? I was wondering what you think is the biggest obstacle for developing working warp drive, and would you see this becoming a reality? And if yes, when? Curious about Charles' theoretical view on this.
37:39 Neil deGrasse Tyson? Ooh, impatient Patreon member.
37:42 Chuck Nice? Pim, here's the answer. Charles has already built a warp engine in his basement. That's and he can't tell you when it's going to be released because, you know, that's classified information.
37:55 Charles Liu? The 1.3 gigawatts are...
38:01 Charles Liu? Well, let me think. Uh, let me see. Okay. The thing that is most blocking our ability to create a warp drive quickly is physics. The actual ability to travel faster than light at this point through the universe that we have right now, uh, we don't have it. We don't have that ability. So you have to find a way to travel through space, but not in the way that everything else travels through space. So can we actually do what the Star Trek folks are thinking? Or Miguel and Cubier said? Where you create a subspace field? And you put yourself inside a warp bubble? Which can travel through space faster than time?
38:45 Charles Liu? Because the warp bubble can, but you can't, right? Or is it some other way? Where you actually have to exit our three dimensions? And go into a fourth spatial dimension? And then come back in? These are the questions. The basic fundamental physics are still beyond us. We can imagine. We can have fun with it on television.
39:07 Neil deGrasse Tyson? Give me a date when we're gonna have it. Next Wednesday. Next Wednesday at 3pm.
39:13 Charles Liu? According to, according to reliable sources? The date is April 5th, 2063. That is according to Star Trek: First Contact. The movie where Picard travels through time and goes to the Borg. Goes and sees Zefram Cochrane in Montana.
39:29 Neil deGrasse Tyson? The one who invented the drive.
39:31 Charles Liu? Correct.
39:32 Chuck Nice? And the Vulcans, the Vulcans came.
39:34 Charles Liu? And the Vulcans just happened to notice it.
39:36 Chuck Nice? And they picked up his warp signature.
39:37 Charles Liu? And that changes all of human history. Right. That event happened on April 5th, 2063.
39:45 Neil deGrasse Tyson? Okay, well, there it is then.
39:46 Charles Liu? Wow. That was, I gotta tell you, that was amazing.
39:50 Neil deGrasse Tyson? Let's get, let's get reality imitating art.
39:54 Charles Liu? Yeah.
39:55 Neil deGrasse Tyson? And make, make that happen. All right, I'm looking, so I might, I'm gonna put that in my calendar right now. Right when we're done here.
40:04 Neil deGrasse Tyson? All right, Charles, always good to have you, man.
40:06 Charles Liu? Thanks so much.
40:07 Neil deGrasse Tyson? All right, love, love to the family. And Chuck Nice, always good to have you there. Gary, we're all in here. Thank you. All right. Startalk Sports Edition Cosmic Queries Grab Bag. That's like the randomest fun anyone can ever have, I think. Yeah. All right. Neil deGrasse Tyson here. Thanks for listening. And as always, keep looking up.
Previous Cosmic Queries – Cool Worlds with David Kipping Next Cosmic Queries – Quantum Computing with Michio Kaku Page updated September 28, 2026 · transcript and summary are machine-generated
