Listener Questions 13: Space water, wormhole colliders and boxes of dark matter
Daniel and Jorge answer questions from listeners, like you! Submit yours, to questions@danielandjorge.com
Learn more about your ad-choices at https://www.iheartpodcastnetwork.com
See omnystudio.com/listener for privacy information.
2020-11-19
41 min
Transcript
Available Results
Generated results are saved to the knowledge database for reuse and search.
No generated results are available for this episode yet.
Extract Knowledge
Pick what you want extracted first. Model, scope, and chapter options appear after a template is selected.
Generated results for public episodes are saved to the knowledge database so they can be reused and searched later.
Transcript
00:00:08 Speaker 1: Hey, Daniel, what's your favorite kind of Daniel and Horry explain the Universe podcast episode. Oh, I don't know, so hard to pick. I do love the Extreme Universe series though. Those are extremely fun. And then you know, I also really love the science fiction author ones because I get to talk to really clever writers. That is every fanboys dream. But I have to admit I think my absolute favorites are the listener questions episodes. Oh yeah, what well? I just like knowing that this is something a real listener wondered about. You like knowing it's not just some crazy detail of particle physics nobody else wants to hear about. What do you mean? Every detail of particle physics is fascinating? That is extremely true. I am Or I'm a cartoonists and the creator of PhD comics. Hi, I'm Daniel, I'm a particle physicist, and I'm the co author of the book We Have No Idea, a guide to all the crazy things we don't yet know about the Universe. Yeah, I'm a big fanboy of that book. Have you spoken to the authors yet? They're really hilarious. Oh man, I can't wait to get their signature, or maybe they can doodle something for me. Watch out though they can just go on and on about particle physics. Sometimes you know there's a danger in everything. But Welcome to our podcast Daniel and Jorga Explain the Universe, a production of our Heart Radio in which we talked about all the things we do know about the universe and all the things that we don't know about the universe. We embrace curiosity and mystery. We talked about everything from the size of the universe to the size of tiny particles. We unwrapped mysteries about the origins of universe, and we talked about whether or not protons will live forever. But mostly we are here to tickle your curiosity, to answer your questions, because science is just people asking questions and trying to figure out the answers, and that includes you. Yeah, and there is a lot to ask about in the universe. There's a lot we don't know and a lot that we are still learning. And sometimes what we're learning is what's on the minds of listeners like you. That's right. You may be shocked to discover that the questions you have in your minds are the same questions as scientists at the cutting edge are asking, and that's not just because you're super smart, but because some of these basic questions we've made very little progress on and we're still at the point of asking questions. So that's why on this podcast we encourage our listeners to send us their questions. To ask those questions. Yeah, and Daniel actually answer them. If you right into our Twitter account or if you email us at questions at Daniel and Jorge dot com. That's right. We answer every email and we answer every question. Sometimes people seem to be surprised when they actually get a response from me. They're like, whoa, You really do answer emails And they're like, aren't you supposed to be doing physics. News flash, I am supposed to be doing physics. But I love answering your emails. Seriously, every time I get an email from a listener, I think, what's this one going to ask? What crazy question that I've never thought of is going to be contained in this little digital package? And it's part of physics also to communicate what you guys know and what you don't know to the public. Right, So in a way, you're answering questions. Is doing physics. Hey, that's a good line. I'm gonna use that my next job performance review. Good luck. But I think you're absolutely right. And one of the things that I love about physics is that the questions are fascinating, but they're also big questions. There are questions that are relevant to everyone. They have deep philosophical implications. How is the universe created, how will it end? What is it all made of? You don't have to be an expert and how particles talk to each other in quantum field theory to know that if you have the answer to these questions, it could change the way you live your life. So physics is fast nating. But also because physics has deep implications. Yeah, and so we get a lot of questions from listeners and every once in a while we like to answer them on the podcast. To be on the program, we'll be tackling listener questions number thirteen, lucky number thirteen. Are you superstitious Daniel about the number thirteen? No? I actually kind of like the number thirteen. Is something cool about it? Really? It's a prime number. I like all prime numbers. Yeah, absolutely, prime numbers are awesome. This is just something about that number, Like seven thirteen thirteen is seven plus six I don't know. It's a cool number. What's your most favorite number? My most favorite number forty two? Of course, the answer to everything, life, the universe, and everything. Well. Today we have a couple of awesome questions from several readers. We have questions about water in the universe, about gamma rays from black holes, and also an awesome question about dark matter. It seems that people are curious about a lot of things, Daniel, People are curious about a lot of things. I get an amazing and hilarious breath of questions. We got a question last week about Santa Claus. What did they want to have? No, well or not Santa is also a physicist. No, but it was a physics related Santa Claus question. They thought, maybe the reason that Santa doesn't appear to age is because he has to travel so close to the speed of light that time dilation has slowed down his clock. Interesting, So I guess if you spend one day a year traveling at the speed of light that, well, that wouldn't help you very much with it, not very much, but you know it works in the right direction. And this was a question from an eight year old listener. So I'm thinking, Hey, that's pretty good. The physics of Santa relativity and the anti gravity of the reindeer, the infrared radiation of Rudolf's nose. What else? Maybe there's a wormhole or like a pocket universe in his bag? Oh man, I think that's your next I find I think that's our next book, The Physics of Christmas. There you go. It was sound really well. Now, so we get a lot of really awesome questions, some of which I can respond to right away, and some of which I think everybody might be interested in hearing about and also take a little bit more digging to answer. So those are the ones who usually feature on these Listener Questions episodes. All right, so let's jump in right away. The first question comes from Greg Preston and he has a question about water in the universe. Hi, Daniel and Jorge. I was listening to your podcast about the art cloud, which I'd like to refer to as a snowball's chance in order, and it got me thinking where all the water came from in the universe. I know water b n H two oh was made from two hydrogen molecules and one oxygen molecule, and I know there's a lot of hydrogen in the world, but I don't think there was really that much oxygen. And then how could there be that much water um not only on Earth but throughout the galaxy, or at least throughout the universe. So I was wondering if you had any idea where all the water came from. I appreciate it. Thanks and keep up the good work. Alright, awesome question, Thank you, Greg. The question is where does water come from in the universe. No, I imagine Daniel. It doesn't just come from the tap. There's no is there a universe tap. No, the universe buys bottled water, usually fancy. It likes sparkling water. Actually, you know, it's usually very bubbly. No, you can't just go out there into space and turn on the tap. But there is actually a lot of water out there in space. Really, how much is a lot? Like huge amounts of water, like vast quantities of water. I think people have gotten the idea that there's not much water in space because they know that NASA is out there on the hunt for water, looking for water so they can find places where it might be possible to have life be started. So people are familiar with this, like search for water, and that gives them the impression like water is rare because we haven't hound a lot of liquid water on surfaces, right, We haven't seen any other oceans out there, right, that's right. So we have liquid water in the surface of Earth, and there's no other body in the Solar System or galaxy that we're aware of that has liquid water on the surface. So that is indeed rare. Liquid water on the surface. You have to have enough water on the surface, you have to be close enough to the Sun so that it melts but doesn't vaporize. But that doesn't mean that the water molecule that the H two O itself is rare. There's a lot of it, I guess. But when you say in space or in the university, you mean like in our Solar system or just in general, like is the universe sprinkled with water vapor or is it mostly only where there are planets? Both? There's actually water basically everywhere. So our Solar system has vast quantities of water. First of all, a lot of the planets have big chunks of water and them like just look at Mars. Mars has ice caps on the poles. North Pole and South Pole have huge water reserves. Now that's not quid water on the surface like you would hope to see if you can find little green aliens swimming around. It's all ice, but that is water. Now, does the Mars Santa Claus also break the laws of physics? Or well, the Martian year is a little bit shorter than an Earth year, so you have to deliver presents more often, which I guess means spending more time at high speeds close to the speed of light. So yeah, Martian Santa Claus ages more slowly than Earth Santa Claus. Oh man, that's the sequel to the book. But it's not just Mars. There are other planets with a lot of water, right, that's right. If you wanted to find water in the Sol system, it would not be hard. Like look no further than the ice giants. Urinus and Neptune are called ice giants because they're mostly huge balls of ice, not just water. Ice is also like methane ice in there. But there are enormous quantities of frozen water in Urinus and Neptune. It's not hard to find water out there. And all the comets in the Orc Cloud, as the listener was suggesting, those are dirty snow balls. So this frozen water all over our solar system. So Uranus and Neptune are mostly water, like H two O water. They're like two thirds ice. Some fraction of that is methane and some fraction of it is H two O water. We're not exactly sure the proportions, but we know it's not zero percent water or one percent water. It's a significant fraction of it is frozen H two So it smelly water, it's not it's like methane. Yeah, it's not Fiji water. It's not water you want to drink immediately. But you know, if you're out there and you're looking for raw materials you need oxygen hydrogen either to drink or to make rocket fuel. There is plenty of water out there. You wouldn't need to like bring water with you from Earth. All right, So there's a lot of water in our solar system. But I guess maybe Greg's question is is like where did it all come from? Did it come from like a supernova? Does it does it regularly made by sons? Or did the universe just come with water? Yeah, it's a great question, and to begin to answer that you have to look a little bit further outside our solar system and ask like, is the water everywhere or is it unusual here? And we find water in lots of places. We find it in the interstellar medium. There's big gas clouds, you know, molecular clouds of basic raw materials that form solar systems, and a lot of them have frozen water in them, and so it's all over the place, and so you ask, well, where does it come from. Well, it's made of two ingredients, right, hydrogen and oxygen. Hydrogen is everywhere. It's literally the most plentiful thing in the universe. The number one thing that happened in the Big Bang was the creation of hydrogen. Is started out like nineties six percent hydrogen, so there's no shortage of hydrogen. The key thing is oxygen, as greg aye. And that's because hydrogen is the simplest element, right, Like it's just an electron and a proton. It's like the simplest thing you can make out of fundamental particles. That's right. You just need a proton and an electron and they come together and they make hydrogen. It's very simple, it's very happy. It's very easy to occur. To get heavier elements, you have to squeeze protons together to get an element like heally them or lithium or something heavier. You need multiple protons to come together to form a nucleus, and protons are positively charged, so they repel each other electromagnetically until you squeeze them close enough that the strong nuclear force sort of snaps them together. And that's fusion that can only happen in the heart of stars. Right, You need like a lot of a lot of it to start fusing, right, Like two hydrogen items won't just fuse out there in space. You need like a whole bunch of them squeezing together. That's right, You need a whole bunch of them. And so you start with a big cloud of stuff, and gravity is the force that pulls them all together, tugs on them, gradually squeezing them harder and harder, until eventually there's nowhere for those protons to go. They get squeezed together and they start to fuse. So you start with hydrogen. The first stars in the universe burned hydrogen and they made something which had two protons in it, which is helium. And then eventually, if you burn enough hydrogen, your stars have helium in them. So the second generation stars tended to burn hydrogen and helium and they were capable of then forming an even heavier element using helium together, for example, to make carbon. Yeah, so you fuse three helium adams and you get a carbon. Right. Yeah, there's a bunch of sort of complicated chains. Once you get just beyond hydrogen hydrogen fusion into helium, you have weird mixtures where you can add hydrogen and helium or multiple ones together. So you can look up nucleosynthesis if you're really interested in the gory details. But basically, smaller things come together. You fit these lego pieces together to make heavier and heavier things, and it gets harder and harder to do. Like you need your son to be hotter and hotter, denser and denser in order to be able to fuse to make the heavier elements. For example, our son isn't heavy enough to make oxygen. Oh, interesting, so we are not making oxygen here in our solar system. That's right. Our solar system star is not heavy enough to have the conditions to fuse carbon together to make oxygen. If you have a star that's like eight times the mass of the sun, which sounds pretty big, but it's not actually that rare because our star is not big on a galactic scale. But if you have a star with a mass eight suns or more, then it can do this carbon carbon fusion and make oxygen, and that's not that rare. So oxygen has been produced in the universe for billions of years, and there's a lot more hydrogen, but there's plenty of oxygen. Well, I guess the question is, if our son is not the one that produced the oxygen, where did it all come from? And so let's get into that question and also into other listener questions. But first let's take a quick break. All right, we're answering listener questions, and their first question came from Greg has Where does the water in the universe come from? So we know that osten is made in stars, except our star does not make oxygen. It's too wall. So where did the oxygen in our solar system come from to make all this water? It came from the same place as all the other heavier elements like the iron and all the other crazy stuff that we need to make our bodies and life. It came from other stars which were massive enough to fuse this and then died and spewed the results of their work across space. And remember the solar systems happen in waves. The first stars which formed very early after the Big Bang, and they were big and hot, and they burned very fast and burned only hydrogen. And then the second generation of stars, which had higher medallist city more of these heavy elements, and they burned helium, etcetera, etcetera. And then now our generation of stars like our sun, but we start from the endpoint of the second generation. Some of those stars were big enough to make oxygen and iron and other stuff, and so we are using those wrong ingredients formed in the fusion of other stars. So every cup of water you drink the oxygen in that was made inside a star billions of years ago, some other stars, not our stars, some other stars, some star which is no longer around. Basically, every cup of water is like a toast. You pour it out for that other star which gave its life, so you could have that drink. And where was this star? Was it like where our star is right now or from far away? That's a great question. Yeah, we know that stars tend to form in bunches, So you get these big clouds of stuff which coalesced in these star forming nurseries. And so our star was formed in a group with other stars from some huge cloud of material which came from a previous round of stars. And yeah, it was roughly around here, but now that cloud is mostly coalesced to form these stars that are our star and the neighboring stars. All right, So there was all this extra water and iron and and lithium floating around and then I guess it kind of got brought together into our solar system and our sun. Yeah, and it's not hard to make water like H two and O like to get together. If you've ever made water, which is by like combining hydrogen oxygen, it's an extremely exothermic reaction, which means it's very tightly bound. So it's not like the kind of thing that's hard to do. Like it's hard to fuse two protons together to make helium, right, doesn't even happen very often inside our star. Like a lot of times protons and protons inside our star refused to fuse. It's very low rate process, which is why are star burns for so long. It doesn't just explode, but hydrogen oxygen. They like to get together to form water. It's very tightly bound state, and so any time they're near each other, you have a few processes involved, but they very often form H two. Oh. Right, But isn't it the case that oxygen likes to form oxygen gas like O two and then then it's happy and doesn't like to interact with other things? Or does even O too love hydrogen to make water? Now you're right, you can have O two, but you have O too and hydrogen and energy around, then it will form H two. Oh. Alright, Well, I guess that answers to course and it comes from other stars. Yeah, And it's really a fascinating question, not just like where is the water, but like what kind of water is it? And how did it all get around? Because there's various flavors of water, like what coconut vitamin water, more like poisonous water and non poisonous water. Like you can have water where the hydrogen has some extra neutrons. This is called heavy water, and that you know, still water is still H two oh, but the hygen has an extra neutron and so it's a little heavier and the ratio of like normal H two O two heavy H two tells you like how it was formed, and we can see these ratios using infrared telescopes and understand like the processes that make it and the origin of water. And it's a fun question like where did water on the Earth come from? Because we tend to have very small amounts of heavy water to normal water. So there's a lot of really fun signs just about water. Yeah, yeah, I think you're telling me the other day that Earth had water initially when the rock formed together, but then it all evaporated and then we had no water, but then water came back in the form of probably comments. Yeah, exactly, we lost all of our water when Earth was hot and it boiled off, and so it had to be replenished, And so we can understand something about where our water came from by looking at these ratios and then looking out into the solar system. Is saying where do we find water with these ratios of normal to heavy water. It's a really fascinating question. Also, water does all sorts of crazy things, makes weird kinds of ices, black ice and normal ice, and man, we could do a whole podcast episode just about the weird chemistry of water, right, yeah, also coconut ice, which is delicious. All right, Well, I guess that answers Greg's question. Water in our universe comes from stars, but they have to be big stars to make them to fuse the hydrogen into helium, into carbon and into oxygen so that it can react with hydrogen. But our son does not make it, which means that our solar system came with water. It was an amenity already. That's right. And fortunately water is basically everywhere in the universe and oxygen lasts a long time, so the water that's in us might eventually one day be part of a future solar system and future life and talked about on a future podcast. Wow, same akials that that I'm spinning out right now as I'm talking might be spit out again along with some physics knowledge. All right, Well, our next question is also pretty interesting. It's a buy black holes and warm holes, and it comes to us from Hannah Hill, Daniel and Jorhee. I keep seeing headlines pop up along the lines of gamma rays from black holes could be worm holes in disguise. Now, I know from being a long time listener that these articles often aren't what they appear to be. Headlines can be misleading, so I'd really love to hear your discussion around this subject. Thank you, all right, thank you, Hannah. Awesome question. The question is do the gamma raised that you see from black holes mean that there's a warm hole inside of that black hole? And it sounds like she maybe she read it in a headline. Was there a news report, Daniel, do you remember seeing that? Yeah, a few weeks ago there was a fun new speculative paper published about looking at black holes and trying to understand the light that comes from them. And you know, the big question here is like what's going on inside that black hole? Is it a singularity like predicted from general relativity? Is there something else weird going on from quantum gravity? Are there connections to other places in the universe? And since we can't look actually inside the black hole because nothing can escape, they're hoping to look at what comes out of the black hole from nearby as a clue to understand like what's going on inside the black hole. So there was a study recently by folks who had a new idea for how to study the emissions from the stuff around the black hole to try to get a clue as to what's going on inside the black hole. Now, are we talking about a specific black hole we've seen, or is this still sort of theoretical black hole. It's theoretical. But the idea is that we could look at the supermassive black hole at the center of our galaxy called Sagittarius, a star, which is the mass of millions of suns, and it has long been accepted to be a black hole. In fact, people recently won a Nobel Prize for studying it and demonstrating that it exists and that it's a huge black hole. All right, So then the idea is that we could maybe study the gamma rays that come from the black hole at the center of our galaxy, and maybe that would tell us something about what's inside the black hole, including maybe a warm hole. Yeah, and you might be wondering, like a whole lot of second, how do you get gamma rays from black holes? Like? Aren't black holes black? And they are in fact black, Like the actual hole itself is black, nothing can escape it. The idea is that there's stuff around the black hole, and like the black hole at the center of our galaxy, there's a huge, massive stuff swirling around it that hasn't yet fallen in, and this gas is really hot and it's squeezed by the tidal forces of the black hole, and it emits a lot of radiation. And these things can be shockingly bright. They're called quasars, and there's some of the brightest things in the galaxy. Right. Yeah, we've I think we've had whole episodes on quasars and blazers and blazers also. But uh, does the black hole at the center of our galaxy have a quazer? I don't think it does, does it, or otherwise we'd be toast. Now, the black hole in the center of our galaxy does emit radiation, and that's one reason why we were able to discover we saw this intense radio radiation from the center of the galaxy. But it's not technically a quasar yet. It's not bright enough. Maybe sometime in the future you can get enough material swirling around it that it become a quasar or vention even a blazer. But that is the way that you can see black holes. You can see the hot gas around them that's emitting this light because it's glowing. Because remember everything that has a temperature will glow, all right, So there is some gas that that is emitting radiation around the black hole, and so it's the idea that then that this radiation tells about what's inside the black hole. Isn't that theoretically impossible for a black hole because you know, nothing can escape it, not even information. Yeah, the idea is to try to look for a different kind of radiation so we know about this kind of radiation. The idea is to look for a different higher energy radiation from this black hole, which might give a signal that there's a wormhole inside. And the idea is roughly like this, like what if the black hole is not just a black hole, but it's a wormhole, meaning that inside the singularity inside the black hole is connected to another black hole somewhere else in the universe. So we have our black hole the center of our galaxy. Maybe there's another black hole somewhere else in the center of some other galaxy, and their singularities are basically the same that spaces like folded or twisted or bent or just organized in such a way that those are the same place, Like they're connected to each other, right, Yeah, they're connected to each other in that the singularity would be literally the same location, like the center of our black hole would also be the center of that black hole. Like space is just you know, a bunch of locations connected. And usually you think of space being connected pretty simply, like this bit of space is connected to the one to the left of it and to the one to the right of it. But in theory you could have all sorts of different kinds of connections. You could have non simple connections, including something which is far away from something else actually being literally connected to it, right and so okay, so then the eight days that there might be a worm hole inside of our black hole and in our galaxy, and so then how could the radiation tells that there is when the next step in the idea is if you have two black holes that are connected by their singularity, then stuff falls into the two black holes, gets accelerated towards the singularities, but essentially then meets at the singularity. And then you have two black holes which essentially function as a huge cosmic collider. They're slurping in particles, speeding them up and smashing them together, forming these incredible collisions which could release a mos amounts of energy. Right, But could those flashes of energy escaped a black hole. I thought nothing could escape a black hole. Yeah, And that's the part of the study which I just do not understand, because they do these calculations. Are read their paper, and they predict that you could form gamma rays at a different energy. Like the plasma balls that are created at the center of these black holes are super duper hot. It's like eighteen trillion degrees, and so in theory, the photons that come out of those have different wavelengths than the photons you normally get from black holes. But the thing that doesn't make any sense to me is how do they get out of the black hole at all? If you have two black holes connected with the singularity. Sure, you might have a super collider creating these crazy collisions at the center, but they're not going anywhere. You need a third black hole or a white hole. You would need a white hole exactly. And so some wormhole configurations are two black holes meeting at the singularity. And in my understanding, that doesn't make any sense to talk about things leaving those black holes, because there are two black holes and the thing can leave them. Another configuration for wormholes is you have one black hole and one white hole. And things fall into a black hole and things leave a white hole. The white hole is the opposite of a black hole. A black hole is a place where nothing comes out and things only fall in. A white hole is a place where things come out and nothing can fall in. So things could get sucked into a black hole and spewed out a white hole, but those wouldn't give you the collisions. To get the collisions, you need two black holes linked, which means you can never see it. As far as I understand, there's a fundamental problem with this idea. So this paper that came out, you don't see it working, like, you don't see how it makes sense. No, it doesn't make any sense to me. And I actually reached out to some theorists and some quantum gravity folks, and it didn't make sense to them either, And so I think, you know, this is a fun speculative idea, And maybe they got as far as, oh, this would be cool. You could create these plasma balls at eighteen trillion degrees inside the heart of black holes, but they haven't actually figured out how to see them, how to get them out. Yeah. Yeah, So the paper itself is a black hole. It doesn't go anywhere. It's a fun idea. Nothing useful comes out of it. It's a fun idea to think about what happens inside a black hole. Like maybe they're eighteen trillion degree plasma balls, or maybe there aren't. Maybe they're pink dinosaurs. Who knows, but as long as they're inside the black hole, we really have no chance of seeing the interesting. All right, So that's the answer for Hannah. The paper is that it doesn't quite make a lot of sense to most physicists because you couldn't get any gamma rays that come out of the black holes that would tell you anything about what's inside, because nothing can come out of black holes. Yeah, exactly, So until then we have to continue to study black holes using only the stuff that's near them, that's around them, that's a strong gravitation of probe what's going on inside the black hole without actually being inside the black hole, right, or somebody could go in and check it out, we would never know. We never know what they find out exactly. They'd be having plasma balls for lunch, but we would never know. Man said, all right, let's get into our last question of the episode, and it's a question about dark matter. But first let's take a quick break. All right, we are answering listener questions and we have one more question here from Matt Hatton about dark matter. Hi guys, my question for you is if I gave you a container with some dark matter inside, what experiments and tests would you perform on it? Alright, awesome question, Matt, Thank you. The question is what would you do with a box of dark matter? Like if somebody gave you like here here, here's some dark matter and they tell you for sure that there was dark matter in it? What kind of experiment? Or are fun games or I don't know what would you dip in it and to eat? I don't know what? What would you do with it? What would a physicists do with a box of dark matter? Do you think? Matt actually has the box of dark matter? And he's like running a contest. He's like, who's got the best idea for what we should do with my dark matter? Winner gets the box. This is a wonderful question. I love this question. It got me excited. I was like, what would I do with the box of dark matter? I can do this or I can do that. It's a fun idea, right, Well, I guess first of all, you kind of have to ask what would the box be made out of, because if it's made out of regular matter, it would just let all the dark matter escape. Yeah, there's a lot built into this question, right, he has a container of dark matter. He has some box which can contain dark matter. And remember, dark matter, we know that it's out there, we know it's a thing, we know it's matter, we know it has gravity, as far as we know, has no other way to interact. It doesn't give off light, doesn't reflect light, doesn't bounce off things using electromagnetic forces or the strong force or the weak nuclear force. That means that if you have made a box out of some super strong material, dark matter would just pass right through it because gravity is a super duper weak force. If you only interacted with gravity, you could walk through walls because gravity is so weak that the gravity of the wall would never stop you passing through it. Your molecules would pass right through the wall just the same way for example, the new trinos or muans passed through the wall. And so what container could you make that could possibly contain dark matter would have to be like made out of like a super strong anti gravity or something even then like it would have to be incredibly dense to build like a gravitational well capable of containing dark matter. You know, even our galaxy is not great at containing dark matter. There's a huge amount of dark matter in our galaxy, but it's mostly fluffy and diffuse because gravity is not strong enough to pull it down together, and because dark matter has no way to sort of like lose energy. It can't like radiate away energy or collide with itself and give up some energy, and so it mostly stays fluffy. Even gravity is not very strange. But let's say, for example, that we had a blob of dark matter. Don't worry so much about the container. Let's just say somebody figured out there's a blob of dark matter right here, what would you do with it? And, like you said, would be really diffused, right, because I think we mentioned in the podcast was that all the dark matter on Earth that covers the same volume as Earth would only be about as much as a squirrel. Right. Yeah, there's a lot more dark matter in our galaxy than anything else, but it's much more spread out than normal matter, Like there's not that much normal matter if you consider all the huge amounts of space in our galaxy, right, there's really massive stars, but then light years of space in between them dark matter. There's a lot more of it, but it's more evenly spread out. And so like you pick a random cubic meter of space that has one or two proton mass is worth of dark matter. And so yeah, if you integrate over the volume of the Earth, you get about the mass of a score. Right, So there's just not that much dark matter like in our neighborhood. It also means that all boxes on Earth really have dark matter in them, So like every box is a box of dark matter. That's right, you are a box of dark matter. I mean that in the nicest way possible. Thank you. I like to think I'm in better shape than square box. But you're a very trim box of dark matter. All right, there you go. Yeah, alright, so every box is a box of dark matter. But if, like I guess, the question is like, if you could somehow contain it or group it together in front of you in a lab, what kind of experiment would you do with it? So that really the only thing you can do in these kind of experiments is to try to interact with the dark matter, and you can go one of two routes. Really one is use gravity. You know that it interacts gravitationally, So what you could try to do is build like a really sensitive gravitational probe. You know, you could have like heavy masses nearby. You can try to study like the push and the pull on those masses to try to get a sense for like what's going on inside this blob. Is it just totally smooth to have some sort of structure, Is it's swirling around. You could try to use its gravitational information by putting heavy masses around it and then watching the effects on those masses. That sort of idea Number one. Oh interesting, Like if you had a really dense cloud of dark matter, you would feel maybe a lot of gravity outside of it, but once you go into the cloud, you would not feel gravity because it's all around you exactly, And you can use that to sort of like map out exactly where is the dark matter in this cloud. You know, gravity is really really weak, which makes these experiments really hard, but we can measure the gravity between sort of like non planetary size blobs of stuff. You can take like an iron ball and another iron ball and put them near each other, and you can measure really small deflections in their motion from the force of gravity. So if you do really really sensitive gravitational experiments, you could get sort of like a map of where the dark matter is in this blob and maybe over time what it's doing, and that could give you a sense for like is it swirling, is it just sitting there? Is if forming structures? Is it like sending you a message that would give you some sense, or just where it is? Does it look like a squirrel? A lot of important questions? What if it is just dark squirrel? So one experiment you would do is you would stick in maybe like a heavy iron ball inside of it and wave it around to try to like map it like see evens clumping or swirling or is it pretty even? Yeah? Or maybe like a whole grid of iron balls and look for any deflections on any of them to give like a three D map for its location and its motion. All right, So that that you said, that's one kind of experiment. What's another kind of Well, the other and maybe much more interesting is to try to figure out if it has any other kinds of interactions. You know, really the deep question about dark matter is what is it made out? Of is it made out of some other kind of particle or non particle or some other new kind of stuff. And if it's made out of a particle, it might have some other kind of way of interacting, maybe some new force that we haven't discovered yet. You know, we know about several forces in the universe electro magnetism, gravity, and strong and weak nuclear force. That doesn't mean that there's not another force. That's just a list of sort of what we've seen so far. But dark matter is something new, and so it might also have a new kind of force. Now to see that, you'd have to have some kind of material that also feels that force. So we'd have to have some new kind of force that's felt both by dark matter and by our kind of matter. So basically, in the end, which you do is you shoot particles into this blob of dark matter and you look to see if they're deflected, and you hope eventually to see one sort of like bent sideways or you know, careening off in a new direction, and that would tell you, oh, my particle bounced into the dark matter and came off, And you could measure the rate at which that happens. An angle which it deflects and get a sense for how strong is that new kind of force. And so you would take this volume of dark matter and you would put it maybe in the path of the large catron collider ring. Would that work? Would that help you if you shoot all those proteons at it or with protons not work? Yeah, that's a great idea. Protons are a good idea because protons of lots of different kinds of interactions. You might also want to try electrons. You might want to build a lot of colliders and shoot all sorts of different stuff at it because you have no idea what's going to feel this new interaction, right, protons of interactions that electrons don't like a strong interaction. But maybe electrons have interactions of protons don't that we aren't aware of. So you want to try a bunch of different stuff. So basically, yeah, you want to zap it with a bunch of different kind of beams and see if you can see any kind of response. But you know, so far people have been looking for dark matter and lots of different ways. But we've been trying varieties of this kind of experiment in lots of different ways. You know, we have huge masses of quiet protons sitting underground waiting for dark matter to bounce into them, sort of the reverse of this experiment. We have winds of dark matter we think are passing underground through the Earth, hoping to hit one of our detectors. We haven't seen anything yet, and so it might be that we just don't have a powerful enough wind of dark matter. And if you had a really dense blob and you hit it with a really powerful beam, you might start to see something. But those experiments are already sort of just giving no result, not seeing anything, so I wouldn't be too hopeful. So really, you you just maybe put it up on your mantle and admire it, because that you can't really it seems like it doesn't seem likely that we can get to make an experiment that would tell us much about it because it doesn't interact with our kind of matter. Yeah. Well, there's one sort of last idea, which is sort of only a half idea, which is like, yeah, put it on your mantle, but also watch it carefully because it might be that dark matter does something interesting and if you make enough of a dense blob, maybe it has some kind of self interaction. Right, maybe it doesn't interact with our kind of matter, but maybe it has some kind of self intera. Actually, they can do something interesting and it might eventually emit something which we can detect. So maybe over a long enough time periods and great enough densities that dark matter could send us a signal. And so another idea is just like build a bunch of detectors around it and keep an eye on. What if you split it in half and then collided them together. How would you do that? How would you accelerate dark matter? Right? Well, I mean if we're talking about heavy iron balls, could could you use gravity somehow to accelerate them? You could use gravity. Gravity is the only handle we have, but it's difficult to build a gravitational accelerator to create, like, you know, a black hole in between the dark matter. Um, so yeah, maybe the gamma rays would help us. Yeah, sure, exactly, that's not a terrible idea. I like it. Let's build a black hole and then when people come and ask why we suck the Earth into a black hole, will say it's because of Matt Hatton's experiently thank you Matt, before are destroying the planet Earth. His fault, but maybe we learned something on the way. All right, Well that answers Matt's question. I think which is it? You would try to probe it and you would try to do experiments on it and see if it can react to anything that we know. I wonder if he was hoping for a more fun answer, like you would maybe dip bananas in it, or I don't know, what's the fun thing you would do with the box of dark matter? To any I would eat it. That's the thing about his question is I think it's trying to touch on this thing, like why can't we figure it out? What would you do if I just gave you some? And the problem is matth that we already have lots of it around us and we're doing everything we can to interact with it, and nothing is responding. And so the problem for understanding what dark matter is not finding dark matter, is not giving access to it. It's just getting it to respond to anything that we've tried. It's very squirreling, it's very snobbish, and it's nut. Alright. Well, those were all our listener questions for today. Thank you so much to Greg, Hannah and Matt for asking the questions and sending them in as usual. We love answering these questions, and if you have questions about the universe or questions you'd like to have us breakdown, please don't hesitate. Send them into questions at Daniel and Jorge dot com. You might get an email back from me or you might get an answer on the podcast, so stay tuned for more listener questions in the future. Until then, thanks for joining us, See you next time. Thanks for listening, and remember that Daniel and Jorge Explain the Universe is a production of I Heart Radio. Or more podcast from my heart Radio visit the I heart Radio app, Apple Podcasts, or wherever you listen to your favorite shows.
Chapters
No chapters available.