How powerful could a civilization get?

00:00:08
Speaker 1: Daniel, how's our podcast doing these days? Are you number one in any territories right now? Unfortunately we are only number three in natural science in the US, behind some like paranormal and bigfoot podcasts. Maybe we should do those topics then we can be number one. Daniel and Jorge explained Bigfoot. How are those considered natural science? Doesn't seem very natural to me. I don't know, but the folks in the UK actually have us as number one in natural science, ahead of the big Foot podcast. So shout out to the UK science listeners. Maybe they don't have sasquatch in the UK, or maybe they call it something different like lockness or be for a guy. I don't know, but it makes me hopeful that will be number one in natural science in other places. Are you thinking globally or are you thinking like solar system? Why? Yeah, let's go into planetary I want to become the top podcast of Martian colonists. Why stop there? Why not go all the way to Jupiter or Uranus? I mean Uranus? Sure? I want to also be number one podcast among aliens eavesdropping on human technology? Do you think we have alien fans? I just wonder if that's going to change who buys ads for the show? What kind of products do you think they would be trying to sell to humans? I don't know, but thanks to cryptocurrency and Venmo, they can actually send their funds interplanetary lee to us on Earth. You think they have Venmo and other galaxies or other planets? Also, how do they do the exchange tree? Don't you need like a central bank or something. We'll figure that out when we build our Daniel and Jorge Galactic Empire, which will include cryptocurrency. I don't know, Man, sounds kind of risky. Well, if we're not going to do crypto zoology, we gotta do crypto something, crypto economics, exo crypto economics, exo crypto podcast comics. I'll be the first person with a PhD in that field. Hi am Jorhammer, cartoonists and the creator of PhD comics. Hi, I'm Daniel. I'm a particle of physicist and a professor at UC Irvine, and I own zero cryptocurrency. Oh how do you know? I mean, isn't it all virtual? Couldn't you virtually own it too? I mean I checked my pockets and I didn't find any. So that's what I mean you wouldn't find it in your pockets, I mean my digital pockets. Man. No, I'm not invested in cryptocurrency, have not bought any cryptocurrency. I don't think that anything I own owns any cryptocurrency. To the best of my knowledge, as my lawyer's advised me to say, I am not in the crypto universe. It might be hard to tell the these days. I wonder like if some mutual fund you buy, buy some other fund that buys another fund that maybe has a little bit of crypto in it. We probably all have a little bit of crypto in us. Humans are pretty cryptic, I guess. But welcome their podcast. Daniel and Jorge explained, do you know a production of our heart Radio in which we attempt to do our best to decrypt the universe and explain all of its mysteries to you. We want to unscramble the craziness that is our cosmos and explain to you how it can be understood in terms of a set of basic physical laws. It seems like so far everything out there can be made sense of. It's possible to assemble simple mathematical stories that describe how balls bounce against each other. How galaxies form, and maybe even what's inside black holes or the fundamental underpinnings of alien economics. It's right because it is a pretty rich universe full of amazing and incredible treasures that you can invest in in order to grow your mind, I guess, And so that's what we do here. We like to talk about it so we can have a pretty good exchange with all of you about it. All we ask for is your time and a slice of your brain to sit with us and enjoy the crazy mysteries of the universe as we try to unravel them. While we are here on this tiny rock, we are able to cast our minds across the cosmos and wonder what's going on out there in other solar systems. Are there aliens looking up at their night skies wondering what we are thinking about and whether we would be interested in buying their n f T s. Yeah, because it's a pretty big universe, and as they said in the movie Contact, it would be kind of a shame if we were the only living Sentien beings in it. It would be a pretty amazing thing to be the only ones in this vast universe that we have some kind of intelligence or podcasts. It would be pretty amazing to be alone, and it would be pretty amazing to not be alone. Either. Answer to this famous question is mind blowing. Does it depend you think on whether you're an extrovert species or an introvert species. I think it's nice to know that they're out there. If you're an introvert species, you might not want to give them a call, but you still want to know that they exist. You know, I think everybody is probably curious about the universe, but there's an insumption there. Right we're extrapolating our experience to the experience of aliens. We're hoping that the is other intelligence out there in the universe because we know that we are capable of joy and love and beauty, and we hope that aliens out there are also having a good time. We hope that they aren't floating in their slime pits and just totally suffering. Would that makes you, I guess, more of an ex overt because you like exceplanetary life. I am more of an ex overt than an extrovert, that's true. I'm more interested in talking to aliens than humans sometimes and learning from them. I guess because if there are aliens out there, there's a lot that we can learn from them, right, there's a lot that we can learn about how to travel through stars, or even just how to make it past our point intilisation to greater things, or just how to be alive in this universe. When you travel, even just here on Earth and experience different human cultures, you learn so much about the basic questions they ask about life, the approach they take. It makes you realize how much of your life and the way you think is kind of arbitrary and cultural. It opens your minds, it shows you the box that you have been thinking in, and so talking to aliens would be the ultimate version of that. Experience could help us understand our context in ways we can't even imagine today, and of course, perhaps help us crack some of the long standing physics problems we're being in our heads against. I feel like maybe we could do that on our own, Daniel, what do humans need help? Can we figure it all out eventually on our own? It's certainly possible that we could figure it all out eventually, But we might not be the smartest species out there, right, I think humans are pretty clever, But it's possible we have a limitation to our fundamental neural capacity that makes it impossible for us to grasp the mathematics that underlie the universe. Is also the possibility of false starts. You know, human science is fairly diverse, but it also has collapsed along a few pathways, choices we made early on, being influenced by geniuses who came along. It's just interesting to think about other paths and intelligent species might have taken that might be more or less fruitful in terms of understanding the universe. I wonder how we would react if one of your students said that to you, like, Hey, Dr Whiteson, I don't think I'm the smartest person in the class. I just don't have the neural processes for it. Can I copy that person next to me for our test? You would have to say yes, Daniel. I think the ultimate exam for an intelligent species is working together to figure out the mystery of the universe. So we're all getting graded on a group project. That's how I see it. Well, it is an interesting topic to think about whether aliens exist out there, And just to be clear, Daniel, nobody has seen or talked to any aliens as far as physicists know. Right, as far as this physicists, no, we have no confirmed communications with aliens. Absolutely, that's a different podcast in the natural sciences. Maybe the Luckness Monster is actually an alien come to Earth to talk to its long lost brother Bigfoot. I think you just found our new gold mine here, fun fan fiction about human fiction cryptozoology. But instead of thinking about what other weird kinds of life might exist in the lakes of Scotland or the deep forests of Alaska, we like to think about what kind of life might exists on other planets and whether it would be possible to communicate with them. If we're going to hear messages from distant civilizations on the other side of the galaxy, will of course need to receive those messages. They'll need to be capable of sending us those messages, so we have to think a little bit about what their civilizations might be capable of. Yeah, and all those this might seem like baseless extrapolation or speculation, it is something that physicists have been engaging for a while, have polished papers on these ideas about aliens and what aliens could look like, and even Carl saying I was sort of famous for chiming in a lot about aliens. You say baseless extrapolation like it's a bad thing. I don't get it usually when maybe in physics the bar is lower. Is that what you're saying? Well, you know, in physics were often tackling problems that are basically impossible. We don't know how to get started, and so what we usually do is we begin with the simplest, dumbest thing, which often involves baseless extrapolation, Like we don't know how to tackle this, Let's just assume a spherical cow and start from there. And we're going to talk about alien civilizations. The only example we have is our own, and so we have to begin at least by making some assumptions about alien civilizations and their similarity to civilization on Earth, knowing all the time, keeping in the back of our heads that we are making these assumptions and that maybe one day we'll figure out how to relax them or break them or get out of that box. And then I guess the point would be that once we meet aliens, you can be like, Hi, I told you so, or WHOA, I was totally wrong? Is that the whole point of it? Yeah, if you think this through and you come to some conclusions, and then you meet aliens and discover they're totally different from what you expected. It helps you think through what you might have misunderstood, which aspect of your assumptions, which step in your line of thinking might have gone wrong. How much of your time did you waste? Well, it's that or just don't think about it. You know that's right. It's do physics or just don't think about it. Those are the two only two options. Do physics or do nothing? Right, I mean, is there anything else on the menu that's right? Well, what else would there be in life to do? No? But when you are tackling really big, hard questions about the nature of the universe and alien civilizations, you don't often have first principles to start from, so you just sort of explore the space using some assumptions to get yourself oriented. Yeah, so this is something physicists have been thinking about, and in fact, there's an interesting framework to think about it. And the question here is what would an alien civilization look like? Can we extrapolate from human civilization? So to be on the podcast, we'll be tackling how powerful can a civilization get? Now? Daniel is as powerful as in like awesome, or powerful as in like will come and kill us? Powerful as in what is there in number one podcast? In the natural sciences in certain countries clearly a leading indicator of cultural value and progress, right, and handsomeness as well. Don't forget there's a clear correlation if you look at a certain data set. There's lots of ways to think about the power of a civilization. But in a very practical sense, if we are going to discover an alien civilization without going there, they need to be pretty powerful because we have to receive their signals, right if they are far far away around another star for us to hear their messages, their messages have to arrive on Earth, which means they need a certain power in their broadcast. And so we can think about, like, fundamentally, what is the energy available to those civilizations? Would they even have enough energy to beam us a message from the other side of the galaxy? You mean sort of like what's their footprint, Like what's their energy footprint? I physicist tends to think about things as like simple black boxes, right, like energy in, energy out. But if physicist things about nutrition, for example, it's just like calories in calories burned, right, physicists model humans as like simple bomb calorimeters, and so here we're modeling like the entire complexity of an alien civilization in terms of like how much energy to have access to and how much energy can they afford to put it to their signal? I see. So today we're serve asking like how much energy and alien civilization might be able to consume I guess so spend or hardness or channel into one signal exactly. It's a way of thinking through our possible future for our civilization. What does that hold? What technology might we develop in the future that gives us access to stars or many stars or many universes. And so physicists have come up with or at least some physicists have come up with a scale to measure how much energy and alien civilization might be able to tap into around them in where they live. It's called the kar dash Off scale. It's not related to the Kardashian Yeah. The scale is how many Kardashians do you have on your social media? And so we've currently maxed that out. We're leading the galaxy. Yeah, you know, I think one is maybe too many on that scale. But it's a kardas chef kardash If how do you pronounce it? I've heard it pronounced kardas chef. And it's a popular trope inside it's fiction also because it's a fun way of thinking about very powerful alien civilizations, and so it crops up everywhere. And a bunch of listeners wrote in and asked us to talk about the Cardassip scale. And are you sure they weren't asking us to talk to a Kardashian on the podcast because that would probably put put us in the number one spot. I reached out to all of them. None of them have responded, all right, So then let's talk about this Cardaship scale here on today's episode. And so, as usual, we were wondering how many people out there had heard of this scale and how it measures an alien civilizations possible energy use. So thank you very much to everybody out there who participates in these questions and answers. It's really fun for us to hear what people are thinking. If you'd like to participate for future episodes of the podcast, please don't be shy right to us two questions at Daniel and Jorge dot com. So think about it for a second, what do you think a Cardiship scale is. Here's what people have to say. I'm pretty sure I've heard of the Cardassi of scale, but I am blanking on what it is. Something in the back of my mind is saying it's something about the size of stars or something like that. I have no idea. I don't know, no have any idea Kardashi of scale. No, I don't know what the kardashi of scale is. But if I had to take a kiss, I would say it is some sort of high energy scale at which quantum effects become important, like in a black hole or something because of the or the very high energy density and also quantum property has become important. All right, maybe we need a we have no idea scale here, because everyone seemed to max it out on the idol no scale. There really was no recognition. I'm sort of amazed. It's given the number of listeners who asked us to talk about this. The listeners a happy example here had never heard of it. Well, that's what we're here for, to talk about the Kardashians and obscue or alien scales that measure their energy. I wonder what the alien Kardashians are like, Oh my gosh, I kind of hope they don't have Kardashians. Maybe the Kardashian scale is how much your civilization has jumped the shark. Well, we have jumped the shark and the Bigfoot and the Lockness monsters. So I think we're in big trouble. We're due for cancelation any moment, the galactic Netflix is going to pull our budget. Huh right, yeah, no, I want to see what happens in season five thousand of Humanity. Which season are we on? Now? I haven't been binging Humans. I'm not cut up. Everyone's talking about it. Everyone's like, oh, you gotta watch this, you gotta see these kids. But who has the time? You know? Spoiler alert, a lot of people die. Sounds like a depressing show. Well, let's jump into Daniel. What is the Cardaship scale? So the Cardassia scale was suggested by a physicist Cardassian, of course, that tries to imagine how civilizations will grow, specifically in their energy use, in order to understand how much energy they might have available to pump into signals to beam to Earth so that we can discus robbed them. The original Cardaship scale has a few stages. But in the meantime people have built on this and expanded on it and taken in all sorts of new directions. So sort of fun framework for understanding how a civilization might grow to tap into the natural energy available to us in the universe. I see. Is it more like a scale that measures how much energy a civilization uses or just kind of keeps tab of where they would get this energy. It's both. It's an accounting of how much energy is available to a civilization, but of course there aren't infinite arbitrary energy sources in the universe, and so it imagines how they might find those sources of energy. And it's broken into three categories. One where you think about all the energy available on a planet, another way you think about all the energy available in the solar system, and then a third where you think about all of the energy available in the galaxy. I see, So like a stage one civilization is one that only has the energy of a planet available to them, or alternatively, you assume that they have access to all the energy that a planet they can have. Yes, precisely, All right, well, let's get into each of these stages and see where humans are and where aliens might be at But first let's take a quick break. All right, welcome back to our podcast Baseless Speculation with Daniel and Jorge about Aliens The first steps in understanding the universe with Daniel and Jorge. I thought the first step was always observation. Daniel insights, well, we've been trying to observe aliens, but we have zero data, and so that's one thing we haven't tried to understand. I see, step one is observed. Step two a is if you don't observe anything, start making stuff up. Is that what you're saying? Yeah, well, also if you don't observe anything, try to understand why you didn't see something. One thing that motivated Cardasi's paper was the famous Fermi paradox, the idea that the galaxy is quite old, certainly old enough for alien civilizations to have developed and beamed US signals, and yet we haven't heard from any of them. So Cardassian was motivated to think about, like, well, how would they send us messages, would they actually have enough energy, and how would they do it? So it's a way of thinking about also why we haven't heard from aliens. Nice see, it's kind of like we they haven't come visited. Why would that be? And we can't see them why would that be? And if you think about different scenarios, maybe you can come up with a way that you could see them exactly. And it might make the problem harder because maybe you discover, oh, it's quite trivial for aliens to have enough energy to beamas messages, and or maybe you discover that in order for aliens to send us messages from across the galaxy, they would have to harness all the power of the entire galaxy. And that might explain why we can't see Kardashians from other worlds, which is a bad thing. No value judgements here, man, this is just science. Well apparently this idea of how much energy and alien species might be consuming or have avail to them is all measured on something called the Kardashi of scale, which, as you said, has three stages. So let's step through these stages. What's stage number one? And is that something we're at or are we pass stage one? Where are we in this stage system? So? Stage number one is a civilization that uses all of the energy available on its planet, meaning all of the solar energy for example, that hits the surface of the Earth. We are not even at stage one. I mean we are capturing some fraction of the solar energy, for example, and digging up fossil fuels that have effectively stored solar energy from the past. But on the Earth, what's available to us is something like ten to the seventeen watts. Watts is a unit of power, so it's energy per second. Is that the kind of watt? It's like, if you had a solar panel the size of the Earth, that's how much energy we would be getting from the sun. If yes, if you can cover the entire Earth with solar panels, so you built like a solar panel that completely made the Earth in shadow, that's how much energy you could theoretically capture, or that's how much energy is falling onto those solar pan Solar panels, of course not efficient, but that's sort of like how much energy you have access to m M And that's interesting how you said that. Basically, like fossil fuels, even what we have here, maybe even wind energy, it all comes from the Sun eventually, right, All that energy originally does come from the sun. Yeah, wind also comes from the sun because it involves heating of pockets of air by the Sun, so all of that originally does come from the Sun. There are, of course, other sources of energy we could tap into on Earth that are not directly from our Sun. Like when you do fission, you're breaking apart uranium. That uranium was formed in some other process, maybe the supernova or collisions of neutron stars, well before our solar system was even birth. So you're tapping into energy sources that have been stored there for a long time. But you're saying all energy solar energy. So when I'm at the gas station actually pouring solar energy into my car, yeah, well, gas is sort of like a solar battery. The idea of the Cardaschef scale is not to argue that the maximum energy you could get on Earth is just to cover it with solar panels. It's just a way to sort of set a level to fix the standard. There's actually more energy available than that. If you could like take the components of the Earth and you fission and fusion, you could release even more energy than the sort of stage one cardassief standard. But it's just sort of like how to define a threshold, all right, So then is the threshold defined by the solar energy we get from the Sun, or like all the energy in all of the uranium and heavy atoms, and maybe even the water, because if you can figure out fusion, you could also fuse water to make energy. Is that how you define how much energy is available on planet Earth? No, it's just the amount of solar energy that falls on planet Earth defines the Cardassie of scale, so you can im principle exceed it without leaving your planet. Right. For example, you could achieve this by doing matter antimatter annihilation, right, Like two kilograms of matter antimatter annihilation every second would achieve kardashef Stage one energy levels even without doing any solar power. But I wonder if maybe in his scale he was more thinking about like long term sustainable energy sources, right, Like, maybe we can figure out fission and fusion, but eventually we're going to run out of these fuel elements in on a single planet. But the Sun is going to be burning for billions of years. That's true, although a lot of these sources would last a really long time. If for example, we could do fusion, you know, we'd need like three ms of hydrogen fused per second to reach Kardashiev stage one. That sounds like a lot, but there's a lot of hydrogen out there on the planet. You know, like a cubic kilometer of water has like a hundred billion kilograms of hydrogen. So a cubic kilometer of water is like hundreds of years of energy at the kardashi of stage one. And there's a lot of cubic kilometers of water out there, So even if you were ignoring solar power, you could achieve this level and do it for a long long time even without solar power. I feel like you're trying to convince me that this Cardashians scale is not really valid, are so I guess what are you saying like or what is the scale supposed to be measuring? Then the scale is just to set a standard to say what could you achieve using the energy of a planet. Obviously, how much energy you could actually extract from a planet over billions of years depends on what's in that planet, for example, how big is that planet, how much mass is there. But this is just like to set a standard in the end. Of course it's arbitrary, but it's also a useful measure. It's an approximate value just to sort of guide your thinking. And you know, one thing to realize is that we are far from that threshold here on Earth. If the standard is two times ten of the seventeen watts, we're about a factor of ten thousand below that. Human civilization uses like ten to the thirteen watts, so we're well below a stage one civilization. Okay, So these stages are defined by wattage. So a stage one civilization is one that uses approximately ten to the seventeen watts of energy. Is that kind of how the scale works. It's like, if you're a sialization and you're using about ten to the seventeen wats of energy, then we'll categorize you as a stage one and usually that made that will probably mean you're an a range of like still stuck in your planet exactly, that's what you're capable of, even if you're stuck on your planet, right, your cable is something of that order. Maybe you figured out matter and to matter annihilation, maybe you figured out fusion. Maybe you've covered your planet and solar panels. Maybe you've build space based solar panels that then beam the energy down to Earth. But if you're a very advancedabilization, but you're still on your planet. That's sort of the order of magnitude of energy that you have available to you. All right, So then where are we You said we're below that maximum usage. Yeah, we're about a factor of ten thousand below officially being stage one crowned by the Galactic Empire as a baby civilization, age one, Carl Stagan estimated they were like a type zero point seven civilization on the carda chef scale, you like, try to make it continuous instead of just having like one to three. And the estimates that were around zero point seven. And it's kind of like a logarithmic scale, right, like difference between point seven and point it is. It's partly like an order of magnitude or something. Yeah, he was using a logarithmic extrapolation. And the reason is that we tend to increase the consumption of energy bio civilization fairly exponentially. Like in the last decade, energy use has gone up by two point three percent every year. Every year, that's a larger increase because it's two of a bigger number, And so people estimate that if we increase our energy use every year by three percent, then in a hundred and fifty or two hundred years, we would be at type one civilization. I wonder if this scale also depends on how many people there are, or how many individuals of a certain species there are. Like you know, if one person was using ten to the seventeen, watch must be a super duper advanced civilization, right with you know, one person being a control all this energy. But as you know, there's like a trillion or trillion trillion people then and each person is using a little bit of energy, then maybe it's not that impressive a thing. Maybe alien Kardashians are dominating the alien energy market. It's a good question how they use is their energy? And I think for a Kardashiv, the goal was to think about what fraction of their energy they might devote to sending a signal to outer space. If they have access to tend to the seventeen watts of energy, maybe they would devote one percent of it to pumping messages to the stars or point oh one percent of it. But it just sort of gives you a scale for what they have access to. M all right, let's talk about what they might use all this energy for. But I guess let's step through the the rest of these stages. So if we're like almost up stage one civilization, what would be a stage to a civilization. Stage two would be too unshackle yourself from your planet and then take advantage of all the energy put out by your star. Now here we are on Earth. Even if we gobbled up all of the photons that come to the Earth from the Sun, that's a tiny fraction of the Sun's energy. The Sun is also shooting out photons that don't hit the Earth, of course, and all sorts of directions, and so the idea is capture all of the energy of your star, not just the fraction that falls on your planet. So stage two is like we've left the Earth and we're living in space. Basically, you don't even have to leave the Earth, and you don't have to live in space necessarily, but you have to have somehow have the technology to harness the energy of that star, which probably means building some mega structure, like a bunch of solar panels that envelope your star to gather all of that energy. Right, But that would be a pretty big construction project. I mean, you would need people living out there just to build something so big or at least have the ability to like, you know, move around space pretty easily, which is a lot more than what we can do now. We definitely are nowhere close to doing that, and you probably would need people out there, but you also might be able to automate a lot of it. You could have robots, for example, that build more robots and then build this massive structure. It's hard to get your mind around the sort of the size of this thing. This would be the biggest thing anybody ever built. If you make it really close to the Sun, it can be smaller, but then it's subject to a lot of solar radiation. If you make it further away from the Sun, then it's got to be like ridiculously massive. Like for example, if you build this thing at one a U, so you have like now a sphere whose radius is the radius of the Earth's orbit, then the inside of this thing is going to be five hundred and fifty million times the surface area of the Earth. So imagine a construction project that rebuilds the service that area of the Earth five hundred and fifty million times. That's definitely not going to be on budget or on schedule, right, Although the positive thing is that it will always be sunny inside of that sphere, right, just like here in southern California, yeah, or Philadelphia. But I mean this is sort of like one way that you could harness the power of the Sun, which is to build a giant solar panel that basically like envelops the Sun so you can capture all of its energy. And what does that take us up to in terms of watta? So Stage one, remember was ten to the seventeen watts. Stage two using all the energy available from the Sun is like four times ten to the twenty six watts. So that's like a billion times or two billion times more energy than Stage one. Really only a billion times to go from the Earth to the Sun. Only a billion times more energy. Wow, you don't seem impressed. Well, as in the Earth super tiny compared to the Sun. The Earth is certainly super tiny compared to the Sun. But the sort of cross sectional area of the Earth, which is the fraction of the Sun's energy that it captures, is approximately one billion of the surface area of a sphere whose radius is the orbit of the Earth. That's why if you built the Dicen sphere, it had to be like many hundreds of millions of times the surface area of the Earth to cover the inside of that sphere. So a fact of a billion is about right. But again, this is just solar energy. Like, we could probably maybe get to that level of wattage if we figure a fusion or fission more efficiently right here on Earth. It's conceptionally possible to achieve a stage to civilization to get that same level of energy without building the dicensphere, developing some other way to extract energy from within the Earth, you know, antimatter or fusion or something else. Crazy. Again, this is just sort of like a scale. The Sun is the cheapest, most abundant, easiest to identify source of energy in the solar system, So what could you do if you could capture all of the energy that it produces? Right? All right, Well, let's step through quickly. What are some of these other stages? If you use all the energy in the Sun, where do you go from there? All the energy in the galaxy? Yes, exactly where else could you go except from our star to all the other stars? So Kardashian's stage three says, use all the energy in the galaxy, which basically is like all the energy in each individual star, and that takes you up another eleven orders of magnitude. Another factor of a hundred billion to four times tend to the thirty seven watts. Member Stage one, which we're not even at is tend to the seventeen watts. So now we're talking about twenty orders of magnitude more energy than the Stage one. Like somehow, if you have solar panels around every star in the galaxy, then you could harness all of the light that is coming out of a particular galaxy. Right in principle, if you didn't think building a dicen sphere was a big enough construction project, you could build one around every single star in the galaxy. I can't even say it without laughing at such a ridiculous idea. But in principle, if you develop the machines to build more machines to complete your dicensphere project, they could just go off to the rest of the galaxy and keep working. Maybe your robots are like a virus. Once they start building dicen spheres, they just don't stop. That sounds like a negative thing to snuff out the whole galaxy basically, right, Yeah, it depends on what you do with that, you know, if the robots developed these dicen spears and then channel the energy to you for you to use for good for building your civilization and feeding your people, etcetera. Awesome. If they just harness the energy the galaxy and snuff it out, then yeah, the galaxy is going to go dark, right, All the stars would be burning inside these dice in spheres. There'll be no more light being released for like astronomy and star gazing and romantic dinners. Well, you can imagine maybe an alien civilization doing this, and we haven't meagined then apparently, and we I think we've talked about this also in our podcast about this possibility, but maybe let's talk a little bit about why this is kind of relevant right to our question of aliens and do they exist and could we see them out there? Because the ideas and not just that there's an alien realization using all this energy, but maybe they're using it in a way that would allow us to communicate with them or at least see them, right exactly, having aliens out there in the universe is not enough for us to discover them. We need to get signals from them and at least up till now we've relied on messages from electromagnetic radiation. That's what we're looking for. You know, the search for extraterrestrial intelligence is scanning the sky for messages essentially in the radio waves, and to produce those radio waves takes energy. When you're a radio station is pumping out music that you like over the airwaves, they're doing so by running an antenna, by sending electricity up and down that antenna, by wiggling those electrons so that they radiate the photons that you pick up. You know how some radio stations are very powerful and other radio stations you can't really pick up in some areas. That's because some have more powerful broadcast antennas because they spend more money to build more antennas and use more energy. So in order to be heard a further distance, you need more energy. Well, I guess maybe I don't understand the scenario that you're imagining here. Are you imagining like there's an alien civilization using all this energy, maybe all the energy in a galaxy and somehow we can pick up on that, or is this scenario more specific where you're imagining like, all right, if there are aliens broadcasting out like hey we're here, signal. How much energy would they have available to put into that so that we could hope to see it? I think Cardiship is imagining the second one, that if aliens are intentionally sending out messages in the cosmos, how powerful could they make those messages? And what kind of civilizations could support ridiculously powerful messages that we could even hear from across the galaxy or from other galaxies. I mean, a civilization that harnessed the entire energy of their galaxy could do incredible things, probably including sending very powerful messages across the millions of light years between galaxies. But also, you know, like galactic engineering projects, and you have that much energy available, you can almost do anything, right. I guess that's a whole separate question is like, would they use some of that energy to send out a signal to other people saying, hey, come check out our awesome engineering. Yeah, I mean, would we write we're currently using a very very tiny fraction of our energy budget to even listen to messages from outer space. We're not even really sending very many, at least not intentionally. You know, as you said before, our use of energy makes us visible from other planets, but not from very far away, because those messages are not broadcast in like a tight beam that sort of generally diffused, and so you have to be pretty close to Earth or have very very sensitive antennas to even pick up our messages. And I guess you're also imagining, or Cardachip was imagining the scenario where you're broadcasting blindly, right, Like, if you're broadcasting blindly in all possible directions and your hope that somebody listens to it, how much energy would you need for that? But if you want a more focused communication, then you wouldn't need that, right, that's exactly right. If you don't know where people are, you need to broadcast in every direction, and so the power of your message falls very quickly. It goes like one over distance squared, just like the brightness of the sun falls as you get further and further away from it, because the sun is not like focused like a laser beam on your eyeball. And a good thing too, So if you're broadcasting your message indiscriminately in every direction, then it has to be super powerful for anybody to pick it up. And it's a concrete example. The signals that we sent from a recibo could only be received by an Arecibo like telescope if it was less than one light year away. And we know that there aren't any other solar systems less than a light year away, so aliens with our level of technology could not pick up our signals even if they were around the closest star. M interesting. All right, Well, let's get into what this could mean for our search for extraterrestrial life and whether or not there are chartsians in other galaxies. That's a very important question. But first let's take another quick break. All right, we're talking about the Cardashian scale, which is a scale that physicists have invented as a way to think about how much energy alien civilizations might be consuming or have available to them to send out, Hey, we're here a signal which we might be able to pick up, which I guess is important, right because if we have a whole project called set to explore or to look for alien signals, it would be good to know if we even have a chance of seeing signals from other alien civilizations, right exactly. And it's a kind of thought experiment that physicists like to think about. Let's make some simple assumptions about the trajectory of civilizations and think about who we're looking for. Are we looking for a fairly young civilization like our own. Are we more likely to only be able to spot very advanced civilizations. So let's try to spend a minute or so thinking about what they might look like, how they might communicate, and what technology they might have available to them. Right, And like you said, like if we were to send a signal out to another story, we would need a ton of energy because the nearest star system is more than a light year way, which means we would need a lot of energy. So I guess to see an alien civilization in another galaxy, or to hope to see an Asian civilization in another galaxy sending out a signal that they're there, we would need to imagine an alien civilization pretty advanced, right, with an access to an enormous amount of energy. That's right, unless we were extraordinarily lucky and we happen to resolve a single star in their galaxy and see them do some crazy construction project on it, or they were manipulating the star itself to pulse with messages that we could resolve. That would require crazy advanced technology and access to energy that we can't even imagine. Yeah, some fraction of all the energy of a galaxy. And so that's where the Kardaship scale would say. It's like that's another stage in that scale, which is like, if you can harness all of the energy in the galaxy, then maybe you might put some of that energy to putting out a signal which would make you visible to aliens or to humans in other galaxies. Right, Yeah, maybe you have a prison planet where you put all of your Kardashians and you just want big flash and warning signs like do not go here, young civilizations. I feel like you just took it to another level against the Cardashians there. Now you're talking about jailing them in planets. Remember we want them on the podcast on Yeah, sorry, I'm talking about a luxurious island just for alien Kardashians, private planet. Yes, and you get to hang out with the Lockness Monster and pick Foot also future guests on our podcast. Yeah, that's right, stay tuned, keep listening. But this kind of thinking lets you imagine the kinds of things that aliens might be able to do if you have access to all the energy of your solar system or at your galaxy, you could like move stars around, you could like obliterate planets. You can build new kinds of stars nobody had ever seen before. You could have a whole new branch of engineering, you know, galaxy engineering. Yeah, and so that takes us to about stage three in the Cardaship scale. Right, that's where you may be built toller panels around every star in your galaxy. Is there a stage four? Can you go bigger than that? Let's keep basically speculating. You want to extrapolate our extrapolation, Sure, let's do it well. Cardasship have ended his extrapolation at stage three, imagining only use of the entire galaxy. But that was the nineteen sixty and it's been a popular topic for people to think about, and so there have been extensions to the Kardaship scale. Stage four says, what if you could use all the energy in the universe? What is in the universe potentially infinite? It is potentially infinite, absolutely, And this stage imagines not just capturing all of the energy from all the stars in each galaxy, but also somehow tapping into that mysterious form of energy, dark energy, which is accelerating the expansion of the universe and has a much bigger slice of the universe's energy budget than just the paltry matter in stars, which you might remember accounts for less than five percent of the energy in the universe. Right, All the matter in our universe only counts for five percent. Right, And there's also dark matter and dark energy. Are you saying, like, even if we harness all the energy coming out of the stars of a galaxy, and even if you take all of the energy in the matter of that galaxy, that's still only five percent of all the energy available to you someone, Right, Yeah, And so if you want to think big, right, then let's attack the biggest slice of the pie. And most of the energy of the universe is in dark energy. Sevent of all the energy in the universe is now devoted to accelerating the expansion of the universe. If you want to build a really big engineering project, you might as well start with the biggest slice. I wonder if maybe dark energy isn't engineering project, Daniel, I mean, if a Slies were basically speculating, I'm gonna speculated dark energy is just aliens making the universe bigger. Well, that's a really clear idea, but you're not actually the first one to have it. One physicist Zoltan Gallantaie argued that if there are civilizations that can do that, they could not be detected because their activities would be indistinguishable from the workings of the universe. We have no baseline to compare them. To write, we are assuming that the universe is driven mostly by natural processes. But if there are civilizations out there that are type four and they've been playing games with the universe, then that's what we've been observing this entire your time. Are you saying that the laws of physics are indistinguishable from the workings of a mysterious being. You're making the case for God basically, well, these civilizations would have almost godlike powers. We think they would still be constrained by the laws of physics. But remember, we don't know what those laws are. We have no understanding of dark energy. Really, we see that this is happening, but we do not understand the mechanism for it or what is controlling it. So it is potentially possible that there's an alien civilization out there with some knob and they are driving the expansion of the universe. I mean This is speculation on speculation, absolutely, but yes, we don't understand the mechanism of it, so it could be down to some alien civilization. This is a reduction of speculations that what you're saying, we're going deep. Yeah, and there are more levels. What what could be more powerful than all the energy in the universe? Well, Stage five says, use all the energy in the multiverse? Right, Why be limited to a single universe when apparently there's an infinite number of possible universes out there for you to harness and manipulate. Yeah, why not, let's go there. So this is a saving that the multiverse exists and that somehow some alien cilvercision has access to all of these different universes and also have the ability to harness their energy. You sound incredulous, and that's for a good reason, because it's a pretty ridiculous idea. You're right, we don't even know if the multiverse exists, Like, are there other universes out there? If the multiverse does exist, is it the flavor of multiverse that would allow us to communicate with other universes? There are some in which these universes are forever separate and can never communicate with each other, and so that would prevent any alien civilization from harness and them. For example, the quantum multiverse from the Many Worlds interpretation of quantum mechanics says that the universe splits every time a quantum object has to make a decision. But you can't ever access those other universes. But in principle there are versions of the multiverse, or the other universes could interact with ours, and so in principle, some aliens might figure out how to manipulate those portals and somehow have a cross universe civilization. I guess, though, well two things. First of all, I guess if you're using all the energy that in the universe, wouldn't you be taking away that energy? Like if you're somehow using the dark energy in our universe, wouldn't that stop the expansion of the universe potentially? Or maybe the dark energy is just like a waste product of something else they're doing. Maybe this is just like the crumbs on their table. I mean, let's think really big. I said, you're saying the expansion of the universe is a byproduct of whatever nefarious or maybe or I guess we can't judge pre judge, but whatever, you know, thing it is they're doing with the inherent energy of the universe. Is that what you're saying, like, maybe there's something deeper than dark energy, and dark energy is just like the smog of whatever process they're using to to steal the use the energy of the universe. M I'm just trying to anticipate what's going to happen in season sixty million when we're only on season five thousand, so obviously there's a lot of dot dot dot happening. But yeah, potentially, are you equating us to like online forums where people are posting fan theories. Is that all physics is fan theories? I think I saw that in a comic strip somewhere. Yeah, exactly, that's x ca CD. All theories are just fan fiction about the universe, And in some sense, yes, that's what's happening here. We're trying to imagine what an alien statilization might be, like, what are the limits on it? Essentially, we're not suggesting that there are aliens out there manipulating the universe and controlling it and that dark energy is just their pollution, but we're just trying to push up against the boundaries of our thinking and wondering what is possible in the end, Do we have arguments that suggest that that would be impossible? Because if not, let's keep an open mind to what might be happening out there. The second thing I want to say was that I feel like that would have been a fun sequel to the matrix to find out that actually our universe is just like a battery for somebody else's universe. Oh, the meta matrix. Yeah, the multi matrix, the multi meta matrix. I like it. It's that one, all right. Well, this cardiship scale is a pretty interesting way to think about aliens, what they might be doing, how big they can get, or I guess, you know, just pushing the idea of what can a sentient species do in the universe, like what's possible for a sentient entity or entities? Yeah, and it leaves completely aside the very important question of what a sentient entity should do with the universe. If you are capable of building Dyson spheres that completely blot out every star in the sky, should you is that the right use for your technology? Should you be measuring your civilization by how much energy of the universe you can capture for your own purposes. Maybe alien civilizations have taken another route, trying to live harmoniously with the universe rather than trying to manipulate it for their own ends. Wait, are you calling God an alien? Technically? Um, God would be an alien right unless they were born on Earth. I don't know how you can have the word technically god an alien in the same sentence. I just don't get into I don't get it either. But this is a natural sciences podcast, so I think that's allowed. Technically, Bigfoot is a lockness monster. That's right. Technically it's all natural science because it's being talked about naturally by scientists, so therefore it is natural science. Yeah, and this is sort of the way that physicists think about civilizations. How much energy do we have? How much energy is available to us? It's of course not the only way to think about civilizations. And one thing we're trying to do in our civilization is actually tamped down our energy use. Right, Well, we talked earlier about how every year we increase our energy used by three percent, and that might take us to stage one civilization. Don't think about that like a goal. It's not like a bad We're gonna put on our civilization. Hey, look, we increased our energy used by ten thousand. Yeah. Right, that would probably be a bad thing for life on Earth if we were using so much energy. Yeah, or be bad if we were using all the energy in the universe and then stopping expansion and then accidentally, oops, we caused the universe to contract and crunch down. Was that us who made the whole universe collapse into the black hole? Our apologies. Please take this voucher and try civilization in another one of our multiverses. We should have gone green much sooner. All right. Well, it's definitely fun and interesting to think about these wild and crazy scenarios. But as you said, it is a little bit part of science to imagine what could be possible, because you might come up with something that you didn't think about before that maybe shapes the future experiment or how you look for answers in the universe. Yeah. And while we sometimes think about natural science as very rigorous and found it in experiments and high precision, an important part of it which is just creative and exploratory and wondering about what is possible. Sometimes the most fun parts of science are when you're tackling a really big question that nobody has tackled before, and so you have to begin with a few crazy, fairly simple ideas. Many things just fun to talk about Indians, which I think, let's be honest, Dan, is really the main point of your choosing your topic. Yes, I always do enjoy talking about aliens, and I hope that the aliens listening to this podcast enjoy our baselist speculation about their lives and motives. That's right, And if the Kardashians are aliens, they're also welcome to come on the podcast. Open invitation to any Kardashian or Alien and or alien. All right, well, we hope you enjoyed that. 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, Apple Apple Podcasts, or wherever you listen to your favorite shows. H