Cosmic Queries: Dark Matter and Dark Energy

Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. I'm Neil deGrasse Tyson, your personal astrophysicist, and this is the Cosmic Queries edition. I have with me Leanne Lord. Leanne, welcome back to StarTalk. This is Cosmic Queries, it's not your first rodeo here. No, not at all, I'm experienced. Thank you. And so to remind some listeners, perhaps for the, or tell you for the first time, we, in the Cosmic Queries editions, we solicit questions from all of our web presence, our social media presence, and a comedian, in this case you, call through them and just send them my way. Yes. And so let's go ahead and do that. Okay, and we do remind people that you have not seen these in advance. No, and the point is not to stump me or anything. Yeah, it's just I haven't seen them, so if I don't know some, I'll just tell you. You're not just gonna make it up? Okay, if you pass, I'll answer it. Well, that's a disaster. All right, so what do you got? So this is probably a puppery. I mean, we're not one subject for a while. It's just on all the universe in this segment. We are, I guess, discussing dark matter and dark energy. Oh, dark, oh, that's fine. And I first took it personally until someone said, no, we're not talking about you. So the first question is from Rocky Kofrin. And- You gotta admit that's a cool name, Rocky. It is, it is pretty cool. And I actually now don't know if that's a he or she. Is that through what social media source did that come? I believe this is from Facebook. Facebook, good. Because if it were Twitter, it'd be only 140 characters. So it's a little longer than that. That's a short question. Okay, I've seen graphs and heard percentages of what makes up the universe. Somewhere around 80% dark energy, 16% dark matter and 4% everything else. My question is, how did we come to these numbers? What instruments were used to make that conclusion? Nice. Well, first of all, I mean, dark matter is we, most of the gravity we measure in the universe has no known origin. Everything we know that makes gravity, like matter and gas clouds and energy and all these things, you add it all up, it doesn't account for all the gravity we see. So that's like the dark. So there's missing stuff. It used to be called missing matter. It used to be called that. And we say, well, how do you know it's missing? How do you know it should have been there in the first place? So it's really too much gravity is what we should call it, not missing matter, because maybe gravity comes from other kinds of things. So you can add up how much of that is driving the universe. And put that in a box. And then you say, hey, the universe wants to sort of slow down in its expansion because there's all this gravity, yet it's accelerating in its expansion. There's some mysterious pressure in the vacuum of space pushing on the universe. That takes a certain amount of energy to do. You put that in a box. You add those two together, it is 96% of everything that matters, no pun intended, in the universe. And so everything we know, all of our laws of physics, all of our understanding of the behavior of matter, motion and energy is 4% of the universe. We understand. We understand 4% of the universe of what's driving the universe. And that's the chart. This is a pie chart. It like cut away 4% of an apple pie. That's all you got. That's all you got. And the rest, we know it's there. And one of the questions was, how do we know how much it is? You can measure how much gravity is out there because you can see the motions of objects. And you can see how fast, for example, we are orbiting the center of the galaxy. You just measure that. We can do that. No, of course, every day. But of course. And once you find out how fast you're going, you can say, well, how much material is between us and the center of the galaxy to enable us to go that speed. These are two very related numbers. The amount of gravity pulling on you and how fast you're going in orbit. They're connected in a single equation. You calculate it up. You say, this should be this much gravity down there. And you count up all the stars and all the gas clouds, all the black holes, everything, and you cannot account for that much gravity. So there's too much gravity. There's, it's a too much gravity problem. That's right. That's very cool. That's how we measure that. Now the acceleration of the universe, we have supernovae, the stars that blow up at the end of their lives, and they're so bright, they outshine the entire galaxy in which they're embedded briefly, like for about a week. So that means galaxy is really, really far away. If one of these supernovae blow up, you say, hey, we just, we just saw you. That was there 15 minutes? It was there. And so you have, and we know how bright the supernova should be, how luminous they should be at a given distance. All right. So like a hundred watt light bulb, put it a mile away. I know how dim that should look a mile away, half a mile away, right in front of your face. You do this with supernova. I know what bright, how, at whatever distance we find, I know what it should be. When you do that, what you find is that the, these distant galaxies are accelerating away from us. They're accelerating away. Oh, I get it. So, these are like our standard candles, as an expression we don't hear much anymore, but it's the metric that we use to know how far away an object is, is how dim the supernova is. And so when we lay it all out on a graph, we find out that where it is versus how long it's been traveling, don't match up, and so they have to have been accelerating to get there. And so you add all that with, we only know four, so we're dumb, stupid, ignorant about most of the universe, which is really cool. It keeps astrophysicists employed. And doing shows called StarTalk. Wow. That's a long answer, but that's a lot of the universe to get in there. Dude, you condensed it so well. That's an entire semester for some of us. Yeah, it actually, yeah, sure. Yeah, 96% of the universe put into three minutes. Wow, well done. Only our personal astrophysicists can do that. I have a sort of related question from Gene O'Donnell. Who discovered dark matter? And I know it wasn't Al Gore. Ah. Sorry, Al. Yeah, he discovered it on the internet. On the internet. Yeah, so dark matter was discovered in the 1930s by a dude named Fritz Zwicky. Not Fritz. That's totally Fritz. That dude, party. When did he have time to discover dark matter? That dude was always at a party. So he was Swiss born, American. I don't know if he was ever naturalized, but his whole professional career was in America. And he worked at Caltech in Pasadena, California, the California Institute of Technology. And he was measuring the movement of galaxies. Now, the example I just gave with the sun and our solar system orbiting the galaxy, he did that same measurement for galaxies orbiting one another in a cluster of galaxies. So he's measuring how fast these galaxies are moving and says, the speed they're moving tells me how much matter should be there to account for the gravity. And he does the calculations and he's off by a factor of five or 10. Right, and he's double checks and triple checks his calculations. Gets, they continually don't match. And he said there's missing matter somewhere. And it was the beginning of the missing mass problem, today known as dark matter. And there you have it. It was Fritz Wicke. I think it was 1936. So he's just covering a math error, is what we saw. I can't find it. More on that when we come back to StarTalk for the Cosmic Queries edition. We're back on StarTalk Cosmic Queries Edition, and I got Leanne Lord with me. Hey, Leanne. Hey, yeah, you know, we're early in on this, but already my head is starting to hurt. I'm trying to wrap my mind around dark matter, dark energy, my man Fritz. Oh, Fritz, we ended talking about Fritz Zwicky. Mr. Zwicky, I'm sorry, let me be respectful. Mr. Zwicky. It'd be Dr. Zwicky. Dr. Zwicky, I'm sorry, sir. Fritz Zwicky discovered dark matter. Back then, it was called missing mass. It was called the missing mass problem. And it's the longest unsolved problem in modern astrophysics. Oh, and not what women are thinking? Really? No, that would be a longer problem. You know, a related, can I give a related comment to that, if I may? It's your show, so yeah. Okay, the study of the universe is the second oldest profession. Seriously? So yeah, so both of these challenges go way back. But yeah, Fritz Zwicky was quite a colorful character, and with a name like that, how could you not be? Yeah. And he was cantankerous, and he would scream at you and pound the table if he didn't agree, but he was brilliant, and he predicted the existence of pulsars, which are rapidly spinning balls of neutrons. And so we should call them Zwicky stars, really, in his honor. I like it. But they would later be discovered, and he had predicted them based on what he had just learned from the newly invented branch of physics called quantum mechanics. So that's Fritz Zwicky, cool dude. Wow. All this because he couldn't figure out women. He goes, forget it, I'm gonna figure out the galaxy. Exactly. That's easier. It's easier. All right, so what else? So this has given you a headache. We'll try to lift that somehow. Yeah, no, no, no. It's, you know, I know when I am playing outside of my intellectual depth, and I am not afraid to admit it. We will make it part of your depth. That's why I come here. Bring it on. So I haven't seen these questions. You got them off our social media circles. Well, our next question is from Andrew Schaeffer. And it's similar but different, I guess, of a kind. It's how much dark matter or dark energy is predicted to be in the universe. Well, so the number that we put forth, well, so let me back up. We measure the stuff. And so it turns out when we try to make galaxies, well, I mean, on a computer. I was about to say, did you just let me in on some top level stuff that I am not clear to hear? We have, yeah, that's slipped out. There are men in dark suits coming in. Hello, gentlemen. What? I didn't hear anything, what? Yeah, look at this light. So we are, so the, it turns out, before we understood how deep the dark matter problem was, we had a hard time making galaxies on a computer. You put in matter, you spin it up, you see if it's self-gravity, cause matter attracts itself, you watch the computer, provided all your formulae are accurately captured in the program. Newton's laws of motion, differential equations that track where things move, and you put it all in there, you load it up and we found out we can't make galaxies. Not only that, we can't make the structure of matter in the early universe, unless we put dark matter in the equations. So something was missing. Something was missing. And so not only does the universe show us it has dark matter, we need it in our formulations of the universe in order to create a universe that looks like the one that exists. So we have good theoretical confidence as well as observational requirement that dark matter is out there. And we think that that missing thing is dark matter and not love. You need love to make a universe. An absence of love. No, it's too much love. It's too much, it's more gravity than we can account for. There it is. All right. So what else you got? I have a question from Robbie Jager. From where, from what source? Robbie does not identify where he or she is from, so it might be a witness protection thing, but still has a quest for knowledge. I have heard that dark matter and dark energy make up the majority of stuff in the universe. Is the mass of all the black holes within galaxies figured into this calculation of stuff? Oh, black holes are ordinary stuff. I mean, yeah, they're exotic for in our lives. Right. But for this 4% of the universe, we got all the black holes, I promise. Oh, so they're in there. They're in the 4% of things that we get out of the apple pie slice, if I understand it. Yeah, so that's why dark matter is really not a good term. We should just really call it Fred, because- We're renaming dark matter Fred. No, because we don't know that it's matter, all right? We just don't know. So to call it that already puts a bias in the expectation of what you would find. And that's not good science. So it's really just, we have no idea what it is. And call it something that doesn't make you think anything. So I just call it Fred. Okay, Fred, I would love to know who you think Ethel is, but all righty then. Well, that'd be dark energy. Then you get Fred and Ethel, there you go. Well, you know what, this actually, I don't see the question here, but I was looking for. You can ask too, you're allowed to ask. No, someone had asked that question. Apparently those were just placeholder names. Yeah, they're placeholders. So that's why. So matter isn't correct. Black holes are dark and they're matter. But they're not dark matter, that's the thing. So that's why dark matter is really. They're dark and they're matter. But they're not dark matter. This is you alleviating my headache? Yes. Wait, wait, I can say more. They're dark, they're made of matter and they matter. But they're not dark matter. I thought you loved me, Neil. You got that? I really. No, are we clear? Five more hours. Just to clear the air. All right, what else you got? Okay, this is from Chris Butler. And Chris says, when I first heard about dark matter or energy, I had the thought that it might be from the visible matter we know of being pulled into black holes and somehow was turned into dark matter or energy. Because all that matter has to go someplace, right? Oh, yeah, yeah. Well, it'd be one thing if black holes ate their dinner and then spewed it out someplace else in the universe or in the galaxy. So if black holes had a digestive track. A digestive track. Then you can think, well, maybe they're turning it into dark matter, like black holes are dark matter machines. But here's the thing. Everything they eat remains contained within them. So you can see as they eat, they have more and more of an effect on the passing of stars near them. And so the black holes have this huge sources of gravity contained within them. We understand that, we got that. That's not mysterious to us. Not only that, we've got a super massive black hole in the center of our own galaxy, the Milky Way. And other galaxies have other super massive black holes a billion times the mass of the sun. And you say, hey, have we accounted for that? Sure, go ahead and account for it. But the mass of the galaxy itself is several hundred billion times the mass of the sun. So I add the one super massive black hole and it's like several hundred billion and one. So it's big as in a solitary thing, but in the scale of the galaxy, it's just, it's dust. Okay, it's big to us, but not big to the universe. Not big to the galaxy. Galaxy. Right, right. So even if we had neglected to count the black holes. All right, who forgot the black hole? Anybody, did we not check this off? Do we have to start at one? Exactly. Even if you forgot them, everything we know about them and their frequency and the likelihood in the galaxy, we got them all. Now I do have a question based on something that you said, that things enter a black hole, but they don't leave. So. Not really. I mean, they sort of leave, but not really. Okay, because I'm imagining that the black hole needs like a massive super colonic or something. That's, because when she blows, it's gonna be awful. Stand back, everyone. Yeah, colonic, I forgot that word. I'd never think I'd ever use that word in an astrophysics conversation. And that's why I'm here. This is what I bring. That'd be a great new storefront, black hole colonics, you know, that would, they would win in the colonics contest, I'm sure. I would see that in an episode of Doctor Who. I feel it coming on. So black holes eat things, and as far as we know, they stay right there down in their center. But over time, the black hole slowly evaporates these particles, and Hawking first figured this out, and it's named in his honor. It's called Hawking radiation. And given enough time, these particles inside the black hole will evaporate from just at the border of the event horizon. That's the place beyond which you don't return. But I throw in all your atoms, they come out one by one over time, very slowly. So it's an evaporation process, and it comes from quantum physics. It's a quantum physics phenomenon, actually. And I can get in the next 30 seconds, because we're going to have to go to break in a moment. So I'll tell you Hawking radiation in 30 seconds. Ready? Ready. Okay, so you remember E equals MC squared? Of course. E equals, energy is equivalent to matter, okay? So on the outside edge of a black hole, the gravitational field is so strong, the gravitational energy is so intense, the gravitational energy becomes matter, right at the outer edge of the black hole. And that matter escapes. So the black hole evaporates because its gravitational energy is getting converted into matter. And you know something, those particles that escape, invented out of the vacuum of space itself, have the same inventory of all the particles that went in in the first place. The black hole did not forget what it had eaten. You're listening to StarTalk Radio. We'll be back in a moment. This is StarTalk Radio, the Cosmic Queries edition, and I'm your host, Neil deGrasse Tyson. I'm an astrophysicist at the American Museum of Natural History, and I host StarTalk. I got Leigh Ann Lord, Leigh Ann. Yes. Thanks for being on StarTalk. Well, thank you for having me back. And I follow you on Twitter at LeighAnnLord. LeighAnnLord. L-E-I-G-H-A-N-N, no one in the world spells it that way, except for you. No, they do not, yeah. My parents got real creative. There you go. So you're reading these questions for me, I haven't seen them, and they're all on dark matter, dark energy, right? Yes. Yes. I have to say, I'm very impressed with Star Talk listeners and fans. These are some very... We got awesome listeners. We have awesome listeners, man. These are some very learned and cogent folks. Learned folk. And to that end, I have a question from William Flynn. And he wants to know, can you discuss how the experiment on the ISS may have uncovered hints of dark matter and why it doesn't interact with ordinary matter? And why does that matter? And if you don't understand, what's the matter? Right. So there was an experiment on the International Space Station. Yes. He was using the abbreviated lingo there. The acronym, yes. No, for an acronym, it has to be a pronounceable word. Oh, so it's not an acronym. It's then a... An abbreviation. An abbreviation. Yeah. We are so full-service here. So NASA is an acronym, SCUBA is an acronym, LASER is an acronym. LASER is an acronym? Oh yeah. What's it an acronym for? The Light Amplification by the Stimulated Emission of Radiation. That sounds really dirty. Can you say that? Is the FCC listening? Please don't find me for that. The Light Amplification by the Stimulated Emission. Of Radiation. So that's LASER. So those are acronyms. You don't see a nim, like pseudo nim. Nim is name, I guess, in Latin or something. Yeah, so, now you, I forgot what the question was. Wow, well, we're gonna learn something else. No, no, no, you can discuss how the experiment is. On the ISS, not an acronym, International Space Station. So International Space Station, as you know, orbits outside of Earth's atmosphere. So there's certain particles that come from space that don't make it to Earth's surface. So if you wanna study them, there are a lot of things that don't make it to Earth's surface. Ultra, most ultraviolet light hitting Earth's zone does not make it through the atmosphere. So when people get a tan or get burned or darken from the ultraviolet light from the sun, that is a tiny fraction of the ultraviolet light that's actually hitting Earth. Most of that gets absorbed up there in the ozone layer, which is why we need the ozone. But that's a whole other show. So the International Space Station is above the atmosphere so we can see things, detect things that never reaches Earth's surface. Among them are very high energy particles flying from the center of the galaxy and they're called cosmic rays. They have very high energy, higher energy than any particle accelerator we have ever created here on Earth. Nature is the biggest atom smasher there ever was. Nature smash, Hulk smash. I'm sorry. I just got fired. So I think it's the, if I remember correctly, there's an alpha proton x-ray spectrometer on board the International Space. You're shaking your head like a cartoon character. I was just taking it in. I just got hit with a particle there. It sounds like some off of Batman's utility belt. No, not the alpha proton x-ray spectrometer, Batman. Right, so it's a device that can measure the energy of high speed, high energetic particles, basically. We can't make it, but we can measure it. No, exactly, yeah. We can't make these particles. Our accelerators aren't powerful enough. Now, there is a hypothesis that dark matter actually is matter, but a matter that exists only in very high energies and high regimes of energy, and it's a whole other set of particles that are perfectly fine existing, but don't interact with our particles. Parallel particles, if you will. I was gonna say racist, but yeah, whatever. And so the existence of these particles has been suggested as the point of origin of dark matter. And so you wouldn't see them because they don't interact with our light. They don't give off light that we know of or can measure. They would have gravity. They would sort of permeate the cosmos through these mechanisms. And so that would be a hypothesis. And there was a detection made just recently, which is why the question was asked for sure. Someone was also on top of current events that hinted that a dark matter particle was discovered on that detector on the International Space Station above Earth's atmosphere. So money well spent. That's $3 billion a year. I mean, what's the universe worth to you? I wasn't prepared to answer any questions today. Can I get a coupon? Because I don't think I can afford the entire universe. I was gonna say a rain check. I'll give you a space check for that. All right, you come back later with a response. So what else you got? We'll do a quick question. With the new found evidence of dark matter, does it change the field of astrophysics in any way? Oh yeah, well yeah, that's an easy question. I'm sorry. If this new particle is the source of dark matter, then dark matter is matter, all right? As I was saying earlier in the show. It might not be. It might not be, it might be something, we just have no idea what it is. It could be like regular matter, regular gravity from another universe leaking into our universe. I mean, who knows, right? So if it is, that tightens up our, the wild ideas about what it could be. So it wouldn't change how we conduct business, but it constrains how science fiction-y you can get by trying to account for it. Ooh, okay. Yeah, there you go. And you're a science fiction buff, right? Just a little bit. Ooh, apparently you're a Whovian as well. Referencing Dr. Who moments ago. When we come back, more of StarTalk's Cosmic Queries edition. I'm here with Leon Lord. See you in a moment. Bye This is StarTalk. I like to think of it as the after hours edition. But it's got, StarTalk Cosmic Queries. After dark. No, because the universe is dark. Yeah, so, the universe in the dark. So, yeah, because day and night is just, that's an Earth thing, you know. Oh, is it really? That's so Earth. That's so Earth, right? So, we solicited questions from our readers and fans and everybody to ask about dark matter and dark energy, which has been in the news lately, and you've been asking them. So, fire away. Yes, these questions are from Facebook. These folks are really stepping in with some great questions. And I love this one. This next one is my favorite. It's from Anthony Dilemmi, if I'm pronouncing that correctly. And very specifically, it's from Mr. Dilemmi's period five eighth grade science class at Cedar Middle School in Hesperia, California. So we know exactly where you are, kids. Now, the question is, would it be possible to capture and contain an amount of dark matter and be able to study it in its purest form? So these are middle schoolers? These are middle schoolers. Okay, so the hormones. My faith is restored. Hormones haven't kicked in yet, apparently. Or we were at a lucid moment in between harmonic fluctuations. So that's a great question, because scientifically, to study anything, you want to bring it in the lab and poke it and turn it and twist it and heat it and cool it. Are we talking about science or dating? Because I'm a little confused now. To the astrophysicist, in that sense, we are the humblest of all sciences, because we do not control or manipulate our subjects. We cannot take the black hole we view and bring it into the lab and kill it, poke it. Because it'll eat you. Cut it open. It is. So it is the gentlest, humblest of all disciplines. Humble and talking about itself, that's great. Well, in... So, one of the other challenges with dark matter is, you can't contain it, you know why you can't contain it? It doesn't interact with our matter. And the non-interaction part means, you can't put it in a box because the thing doesn't even see your box. If it saw your box, the box might contain it. Dark matter permeates all space and all matter. Okay. Without you knowing it. But we measure its gravity, all right? We know that its gravity is there. So what we might need is some kind of a gravitational bottle. I wouldn't know how to make one. But the same challenge arises with very high temperature plasma, not blood plasma, this astrophysical plasma, very hot gas. The sun is a ball of plasma. Right. All right? Aurora, the Northern Lights, that's plasma. All right? Plasma is like a lot of the universe. You don't often see it walking down the street. But plasma is everywhere in the universe. Plasma is so hot. The plasma like in the center of the sun is so hot. How do you carry that around? It vaporizes any container you put it in. So you need a special container, and the best way we know of is a magnetic bottle. Okay. You create a magnetic field in the shape of a bottle, put the plasma in it, so it's not touching any matter, otherwise it would have vaporized the matter. It's touching a field. So with dark matter, we would need like a dark, we would need something made of dark matter on one side, and made of regular matter on the other, in the lining or something, so that it doesn't penetrate that membrane, so you can carry the thing around and bring it into the lab. But you know what the biggest problem? Dark matter doesn't even interact with itself. So- We need a therapist in here. What's the matter, dark matter? Why aren't you talking to yourself? What's going on? So with regular matter, we know we interact with ourselves, because we can collapse and make solid objects. What is a solid object but a collection of atoms that got to know one another and are stuck to each other. Like marriage. So we, in the 4% of the universe that is matter, can actually create solid objects. Okay. As far as we know, dark matter cannot. Create solid objects. Yeah, because it can't interact with itself and stay stuck to itself. So that makes containing it and studying it in all the traditional ways a challenge. So Schrodinger's cat, not dark matter. Not dark matter. So we've got like a half a minute. What else you got? Well, I like answering questions in sound bite mode. I love it. Okay, well, from Robert Atalo. Is dark matter convertible to dark energy as regular matter is convertible to regular energy? No, they're completely, as far as we know. As far as we know, they have nothing to do with one another. Maybe. Is this where the naming thing becomes a problem? Well, here's the thing. In principle, if energy can become anything, all right, E equals MC squared. Yeah, he says it here. We got the, if energy can, maybe I can take our energy, take our matter, convert it into energy, and then turn that energy into dark matter. I think in principle, you could do that, but I don't know how. Okay, that's honest. Yeah, so when we come back, we will enter the last segment of Cosmic Queries, and it is the lightning round. Be there. We're back at StarTalk After Hours. StarTalk, the Cosmic Queries edition. This is the final segment of The Hour. And it's the lightning round. Because we get so many questions, we gotta do one where I give you sound bite answers. Yes. All right, so let's do this. All right. Leanne Lord. Now this question, and we're gonna do this fast, is from Patrick Seidelik, and he says, how did dark metal come into being after the Big Bang? We have no idea. Next. Wow, Joey Sellers, is dark matter energy increasing? Wait, wait, wait, but we know dark matter was there from the beginning. We know it's been there from the beginning, but we have no idea how and why it came into being. So we have to unring the bell because you're unlightening that question. There you go. Joey Sellers wants to know, is dark matter energy increasing as the universe expands? No, dark matter is, as far as we know, the same in its proportion, as a fraction of the total gravity in the universe, that's the same, and gravity is staying the same, so we're fine. Okay, Casey Wheeler Becker wants to know, how does dark matter influence time? Ooh, dark matter, like anything else in the universe that contains energy, Einstein's special theory of relativity says that time slows down in the presence of high sources of gravity. And so if you have a region where there's a lot of dark matter, if you can find a place near that dark matter that is high gravity from that dark matter, your time will tick more slowly. Your metabolism will metabolize less quickly. Not going there. There you go, next. Larry Bellomo wants to know if dark matter does not interact electromagnetically with ordinary matter, how does it exert its influence on the atoms and particles that make us? It does not influence any light. You cannot see it because it doesn't either absorb, reflect, refract, disperse light. So that's as dark as you can get. The light does not even know it's there. But what light does is not the same thing as gravity. It's got gravity. We can talk about gravity without talking about light. And it's got gravity and we feel it. All right, what would happen if all the dark matter in the universe suddenly vanished? Awesome question. If all the dark matter vanished, our galaxy would fly apart because all the speeds of the orbits that all the solar systems have is the right speed for the regular matter plus the dark matter's gravity to contain it. If you'd instantly take away the dark matter, we fly away and all the orbits go cockamamie and galaxy clusters fly apart and everything goes haywire. Wow, I'm actually starting to get this. Okay, Robert Atala wants to know if the Higgs boson gives mass to regular matter, does it also give mass to dark matter? Go Robert. First, I don't know the answer to that question, but I would guess that particles, if the Higgs boson, which interacts with our matter, could interact with dark matter, then we'd be interacting with dark matter. Ah. So, the Higgs boson, I'm judging this. I mean, I got people I can call on this, but. We got people. I got people. So, the Higgs boson is talking to us and our kind of matter, not the dark matter. Unring, unring. Dark matter might have its own Higgs boson. Oh, see now. Giving mass to it. And wouldn't that be cool at the Higgs boson bar, you know, where all the Higgs bosons hang out. That's what they're talking about. Next. Jesse Turner wants to know, could dark matter and gravity be anything like the north and south poles of magnetism, like the opposite forces in the universe? Ooh, he's into like the good and evil and the up and down and the front and back. It's unlikely only because there's six times as much dark matter as there is regular matter. Rather, there's six times more gravity about which we know nothing than there is gravity about which we think we know everything. And so unlike magnetic poles where they're equal and opposite, these may be opposite, but they're certainly not equal. All right. So, Dr. Oliver Gebberdinger, how much can we learn about dark matter with gravitational wave detectors like LIGO and LISA? Ooh, nothing. All right, next question. No, the problem is the gravitational wave detectors, LIGO, the Laser Interferometric Gravitational Observatory, that would be a what? That's an acronym. An acronym. See, I can learn some stuff. Okay, so LIGO is a great big physics experiment that is looking for ripples in the fabric of space time caused by disturbances in the The force? distribution of matter in the universe. Matter can get collapsed densely enough to create a ripple. If you're spread out like dark matter is, you're not making ripples. All right, so everything I know about LIGO tells me that it's going to measure our matter, not theirs. Got it. All right. Richard Smith from Frisco, Texas. Love it. In what ways might dark matter affect the rotation of galaxies? Oh, well, okay, we hinted that earlier in the show. Dark matter enables galaxies to rotate as fast as they do. Okay. Pure and simple. And the mismatch between what pulls on the stars and the speed the stars are going, that was discovered in 1976 by Vera Rubin. She's still alive, a senior astronomer, an astrophysicist in my community. Cool chick. She discovered that in 1976. She discovered that galaxies needed dark matter as well. Give me one more, quick, and we gotta call it. Brandon Neal, if dark matter has a gravitational pull and we don't see it, could it hinder space travel outside our solar system? No, because it's so thinly spread across the galaxy. It's all around you. No, it's not in the way. Leanne, we gotta wrap this up. Thanks for being on Star Talk Radio. Thank you. And I'm on your list at veryfunnylady.com. Get to know where you perform as you travel the countryside. This has been brought to you in part by a grant from the National Science Foundation. I'm Neil deGrasse Tyson, your personal astrophysicist, bidding you, as always, to keep looking up.