#678 - Avi Loeb - Will Humanity Ever Become An Interstellar Civilisation?

32:39In your opinion, what are some of the most promising ways that we could travel across interstellar distances? What have you thought about when it comes to this? Right. So first I should say that irrespective of what we do about our own industrial pollution and global warming that we trigger by our technologies, there will be an inevitable global warming that will basically boil off the oceans and that will happen in about a billion years because the sun is getting brighter and the calculations of the evolution of the sun imply that there would be boiling of the ocean as a result of the interplay between the the earth's atmosphere and the ground.

33:33So we don't have more than 20 % of the lifespan of Earth to continue life as we know it. And most of the stars form billions of years before the sun. And therefore stars like the sun with planets like the earth already went through that. a lot of them, billions of those. And we probably didn't hear the cries for help from those civilizations who decided to stay on the planet. It was the biggest item in the news reports, not so much the global warming they make as a result of the technologies, if they happen to overcome that. It was the fact that they just sit at a fixed distance from their star and the furnace is getting hotter.

34:18So you have to move out, but you can't, if you are stuck to the planet. And perhaps they had some major exodus in spacecraft, living the planet, that we are not aware of. There must have been a lot of tragedies. That's what I'm trying to say over cosmic history. We just tend to think about stars and say, look, these stars evolve in this way, in that way, based on the physics we know. But we are missing the human perspective of just imagine the star evolving in the way that we expected to. how many tragedies of other cultures, other technological civilizations happen in the Milky Way galaxy alone.

34:57And now there are these completely desert -like surfaces of planets that used to have life as we know it. And it's really tragic. A lot was lost over cosmic history. Now if you ask me, what would the future hold? So, actually, frankly, I'm very proud of our technological kids, okay, which at this time are the artificial intelligence systems that we are developing and they are growing in their capabilities exponentially. So it's possible that by the end of this decade, they would surpass by a large margin the human brain, okay. And I'm proud of that. I don't see that as a threat because it's not obvious to me that biological creatures like ourselves are any different than the primitive you know single cell organisms that were on Earth to start with and they were replaced by more advanced entities and so perhaps we are just one phase in the evolution and ultimately it will be all about artificial intelligence and self -replicating probes that are not biological.

36:16Okay, we we of course learn from nature, we are trying to replicate the human brain, we are trying to make a 3D printers that will produce three dimensional objects. We haven't yet produced a self -replicating car, you know a car, even a car that can repair itself like the human body that you put a bandaid on it after an accident and it will repair itself. We don't have that And it will take us a little while. But ultimately, we will get to the point where artificial intelligence carries the torch of intelligence, at least here on Earth. And I believe that it should do so also in space, because when you send a probe to interstellar distances, it would take millions to billions of years for it to reach any destination.

37:02And that means thousands of light years away and any such probe cannot wait for guidance from the senders. It will take thousands of years for a one -way communication signal. So they need to have their brain if you want them to function when they reach their destination. Obviously artificial intelligence is a better path forward than biological brains because the very vulnerable, Biology is very vulnerable to cosmic rays. You know, you can't survive in space for more than a few years exposed to cosmic rays, even if you were a space suit. And that's one problem in going to Mars that doesn't have an atmosphere.

37:41We would need to go into caves, into lava tubes to be protected from cosmic rays. But moreover, human lifespan is very limited and this would be millions billions of years. So it's much better to send technological gadgets, potentially that would self -replicate. And that's the way I see it. Now they will carry whatever tasks we provide them with. Maybe we can ask them to replicate what we care about here. So instead of sending what we have here, by biology the way we have it, we can perhaps have them seed biology over at great distances by using their own materials on a planet that appears to be habitable or create whatever we feel like out there.

38:29And to me that's the best path forward, sending the type of equipment that can carry the intellectual DNA, whatever we care about, elsewhere and reproduce it wherever we want it, if we want to replicate it so that we have many copies of it. Now of course in the solar system, we might bring people to the moon, to the to Mars. And then it would be interesting to establish colonies there, but this is not really going very far from the sun and it would not solve the long -term issue of longevity. So I do believe in technology leading the way. And of course, if we find that someone else did it already that would inspire us, that would give us a glimpse at our technological future.

39:22That's why I was actually, I'm jogging every morning at sunrise, and I did so also on the ship that was fittingly called Silver Star. And I had a filming crew with me, and you know there were 50 filmmakers and producers and directors that contacted me they wanted to be on the ship and I selected one but the director of that filming crew that he decided to film me one morning on the deck of the ship when I was jogging and he said to me, are you running away from something or towards something? And I told him I'm running away from some of my colleagues who have very strong opinions without seeking evidence and I'm running towards a higher intelligence in interstellar space.

40:14Yes. So what you're suggesting is it seems like you think it would be unlikely for a human or a generation ship of a series of humans to go from Earth to some other star system. like let's say Proxima Centauri, Alpha Centauri, etc. You think it's much more likely, much more feasible to go artificial intelligence, put it on a ship, maybe have a desktop encoder for bioengineering or something like that. It's got the code. It gets there. It then deploys the code. I think I understand how you could see that as a solution. I don't think that that's going to satisfy most people's feeling or their desire for human civilization to continue.

41:07It will not satisfy most people's desires, but just think about a dandelion flower. Okay, what does a dandelion do? It's sense of seeds that are carried by the wind And they carry the DNA of the dandelion flower and establish new flowers. Now you might say, oh, that's not satisfactory because as a dandelion flower, I really want to be out there in other places. But no, that's not what nature cares about is longevity of information content. And in the case of the dandelion flower, it's not the identity of the single dandelion. actually for humans as well, you know, all of us die, right? So we have kids that carry our DNA.

41:58We gave up on us living forever or some people didn't give up but we don't have an option. Okay, let's put it that way. And what I'm saying is if you think about it more broadly, it's not so much about yourself as an individual. It's about maintaining the longevity of what you care about. And the dandelion flowers, at least from the point of view of biology, cares about having more dandelion flowers, like preserving the beauty of the dandelion flower. And therefore, it doesn't have any umbilical cord connecting it to the seeds. You might say, if it wanted, it could have been connected to the seeds.

42:42No, but that doesn't work very well because then you need a long wire that goes all the way to where the seed lands on the floor. And only then the Danloin will learn something about what the whereabouts of the seeds. But in the way that nature does it, it just sends the seeds with the wind and they do their job. And so there is some trust in the system. So in the same way that you send spacecraft with AI somewhere and you don't communicate with it because it takes a long time. It's very cumbersome for you to communicate with it. You just trust it. It will do the job. And that's the way nature works.

43:21Do you think that we will ever physically visit another galaxy, whether that be an AI robots, whether that be a spacecraft that has the seeds of our Noah's Ark, spacecraft, craft knows arc. Obviously, I'm aware that we're talking about, oh my God, we found something from outside of the solar system and I'm saying, why don't we take it one step further and get outside of the galaxy? But what do you think is that something that's realistic? Could we get the ultimate way to elsewhere? Here is a fact of life that we need to accept that the universe is not just expanding. Its expansion is accelerating.

43:59And that means that any distant galaxy beyond the local group of galaxies, the ones surrounding the Milky Way. Any galaxy farther away than a few million light years is running away from us at an ever -increasing speed. And once the universe will age by a factor of 10, all these galaxies will recede away from us faster than the speed of light. So even if you build the fastest spacecraft that moves at the speed of light, you won't be able to catch up with them. And if you ask me, there is only one galaxy outside the Milky Way that we have a chance of getting to, I mean, we could aim to get to more, but that would require proportionate speeds that are getting close to the speed of light.

44:49But the one that we have a good chance of getting to is the one that will collide with the Milky Way and merge with it. That's a cheating. I knew you were going to give that answer, and that's cheating. We We can't wait for Andromeda to come to us. That's not the same thing that I meant. So I actually did a calculation and asked them, suppose you move at a higher speed than chemical rockets, how far can we go? And if you have a spacecraft that moves 10 times faster, you can go within the so -called Virgo cluster of galaxies that's within a distance of some tens of millions of light years. We can do that.

45:35But you need the propulsion scheme that is 10 to 100 times faster, 100 times would buy us that. Otherwise, it's just the universe expansion is too rapid. So I can imagine us getting to other galaxies as long as we can make our propulsion, let's say 100 times faster than all the space raven that we launch so far. And of course, there is a benefit to that because then we can all settle in a bigger environment like the center of the Virgo cluster includes the galaxy M87, which is a giant elliptical galaxy and there are many more stars there than the Milky Way has by a factor of about the 100. So, you know, we will just have a bigger party over there as the rest of the universe receipts away from us.

46:27More resources. And actually, I had a correspondence with Freeman Dyson about a decade ago on this subject because what I pointed out is that as the universe is accelerating, you know, we will be left in a lonely place. And he said, why I don't be contact all these other civilizations out there far away and arrange a project of cosmic engineering where all of us will come together by moving our stars with us. And I said, that's too much work. I mean, we can do much better by just simply going to a cluster of galaxies like the Virgo cluster and finding hundreds or maybe thousands of times more stars in our environment.

47:10And then instead of us moving stars, we can just go to where the stars are, which are clusters of a cluster of galaxies nearby. Okay, so this is kind of the same as cosmic fertile ground, so to speak. Yeah, so I know that you mentioned about how galaxies are moving apart. They're going to move apart at ever, ever increasing speeds. Is the Virgo cluster, even though they are distinct individual galaxies, are they sufficiently gravity bound that that's going to stick together, that's not going to blow apart, is that right? The big of last I will stick together, but if we don't go there, it's going to go away to go.

47:48It will move away from us. So what we need is to go there and then we'll have you know the company of let's say a thousand times more stars than the Milky Way has. So you might imagine a situation where we are not the first to recognize that, that in fact other civilizations decided to do that and then you have a flow of these spacecraft towards the center of the Virgo cluster right now because everyone recognizes that they want to be there. The race to the fertile ground. Well, I would call it the cosmic party where you can celebrate until you exo until the lights go down and the lights the lights will go down if you ask me when would that happen?

48:31That would happen when the smallest stars will burn up their fuel, which will happen when the universe will age by another factor for almost a thousand. So in 10 trillion years, that's when the tiniest stars will go away. And those are the most common stars. So we are fortunate. The nearest star to the sun is actually a dwarf star, Proxima Centauri and it would live for trillions of years. You know the sun will die at an age of 1 % of that. So it's 100 times longer lifespan and obviously if you want to get the light from a nuclear furnace like a star then we want to come close to a dwarf star, like Proxima Centaurion and amazingly it has a planet in the habitable zone.

49:30But then you might ask why are we close to a star that is not typical? If most of the stars are dwarfs, why do we reside next to the sun? And there might be a reason for that because these furnaces, the dwarf stars, you know, they're much fainter because they have less fuel and they burn it more slowly than the stars like the sun. So in order to keep yourself warm, you need to get closer to them. In the case of Proxima Centauri, you need to get 20 times closer. That's where the habitable zone is. And then when you are so close to a star, you are vulnerable to the irractions on the star of the flares.

50:07And those can remove the atmosphere of habitable planets. So it's possible that the best place is being close to a star like the sun. but obviously, you know, in the future, the sun will not stay around and we would, we could create our own nuclear energy. You know, we can use a nuclear reactor to provide all of our energy needs. Well, my favorite theory, one of my favorite theories about far -flying future civilizations is the idea that we would wait until you get really close to heat death of the universe because it's then very, very cold, which means that if you want to run computer systems, they can burn off all of their heat.

50:53As a byproduct of that, they can be kept cool, they can run more efficiently. You're now doing simulations within simulations, within simulations of you and all of your ancestors, and it's this blissed out, completely perfect world that you want to exist in, or whatever artificially recreated consciousness. you can do that much more easily when the universe is much cooler. So yes, you have an energy problem because you no longer have as much energy that you have access to, but I've seen a number of theories that talk about almost going into hibernation, super advanced civilizations going into hibernation, capturing energy or finding a way to create their own energy for as long as they need to, and then switching off, or going into standby mode, waiting for the universe to get down to a requisite cool temperature, and then switch similar to some people as they get old, they go on a diet that keeps them more healthier so they can live longer.

51:51But of course the best way to prolong the longevity of your DNA is to have a lot of kids that will have more kids, that will have more kids rather than you. And so here I come back to the idea that if we, you know, by that time, it's quite likely that whoever is around will figure out how to make baby universes. And by creating baby universes, can basically put whatever you want in those babies in terms of their qualities such that you will know that life will continue in them. Have you thought about how long the average civilization that doesn't become interstellar would exist for obviously. Well, that depends a lot on how intelligent they are.

52:42Because if you look at what we do, we spend $2 trillion every year on military budgets. We are thinking about how to kill other people or how to protect ourselves from being killed. You know, that was the truth, you know, when we were in the jungle, you know, and had to survive in zero some games. It's not true anymore. We could have worked together instead of conquering small pieces of land and being proud of that. You know, we are talking about, you know, the surface of this rock that we happen to be born on, like why is that so valuable? Why do we need to feel superior relative to other people just for superficial reasons, like the color of their skin or the ethnic origin?

53:31And this is completely ridiculous if you think about it from a perspective of intelligence, yet we spend two trillion dollars a year on that. Now imagine if we were to find a sign of a cosmic neighbor and we will tell ourselves, wait a minute, that makes no sense. Look at this other civilization, they live much longer, look at the technologies, they develop, why aren't we having a different set of priorities and and then we will remember the words of the song by John Lennon who said the imagine all the people living in peace and we would say oh yeah that's a good idea let's live in peace and let's use then we will have a surplus a two trillion dollars a year what can we do with it we can use it for space exploration and I did the calculation I did the math and with that budget, we can send a probe to every star in the Milky Way galaxy by the end of this century.

54:29Billions of probes by the end of this century, sending them. Of course, it will take them time to get there, maybe billions of years, but we can just do that. Now, imagine another civilization who reached this conclusion. They have their own John Lennon, they got their own inspiration, There are more intelligent than we are. There are not wasting resources on fighting each other and conquering a small piece of land on this rock that they were born on. Instead, they say, let's work together rather than kill each other. Let's not feel superior relative to each other. Let's thrive towards a better future.

55:04So prosperity is recognized as a priority rather than zero sum games. And imagine them sending props everywhere. And then these props make their way. And by the way, the speed of those probes that we send so far is at least 10 times smaller than the speed needed to escape from the gravitational pull of the Milky Way galaxy. So if other send probes like that, they would keep accumulating in the Milky Way galaxy over cosmic time and over billions of years. So just like plastics in the ocean. And many of those will not be functional anymore. Just imagine Voyager, billionaires for now, it will not be working, it will just paste trash.

55:50And just like plastics in the ocean is trash, but it keeps accumulating. And the same would happen with all these probes. That's what I'm talking about. Let's check out Beck Yard and see if there is a tennis ball thrown by a neighbor. Right. We have the difficulties that are faced in going into stellar, pale in insignificance in the different difficulties going into galactic. Talk to me. Can you just one thing that I was really interested by? No matter what the spacecraft is, let's say that it was seeded with a tabletop bioengineering 3D printer that can recreate human babies in a test tube or something.

56:31Can you just talk me through the journey, pick any star that you want, pick any star that you think looks like a nice piece of real estate within the Milky Way galaxy. Can you just explain what the major hurdles upon that interstellar journey would consist of? I know we've got the art cloud, we've got different things that we need to get through. Like what are the main hurdles that we need to get past? Right, so first I should say that even biology we should not dismiss it altogether because just recently there were some warms found in the Siberian Parmafrost and They were frozen and after they were rejuvenated in the laboratory they came to life 46 ,000 years after they became frozen 46 ,000 years.

57:22So one can imagine engineering biology perhaps to survive interstellar travel that that is something for the future So we don't yet know if it's possible, but it may be but then in terms of the timetable So let's imagine the kind of spacecraft we are launching right now because that's what we are doing. I mean I of course am leading very ambitious initiative called star show to launch spacecraft that the fifth of the speed of light to the nearest star, it will take 20 years, but we are not there yet, the technology is very challenging. So let's imagine chemical rockets of the type that we used.

58:02And so a chemical rocket, just like Voyager 1, Voyager 2, Pioneer 10, Pioneer 11, and New Horizons that are making their way out of the solar system. So these were launched over the past 50 years. Okay, so they are still deep inside the solar system. The solar system, by the way, the or cloud is a hundred thousand times larger than the earth's sun separation. Okay, so these spacecraft will exit will get to the outskirts of the solar system, the edge of the or cloud, which is, by the way, halfway to the nearest star, proximity, they will get there within about 10 ,000, 20 ,000 years depending on which spacecraft you are talking about.

58:46So we're talking tens of thousands of years. Okay, that will not be functional. We may be gone by then. That's another lesson that you can look for packages in your mailbox while the sender is dead. That's the advantage of that compared to the method of city to look for a phone call, to search for someone sending you a radio signal. It needs to be active. So here, you know, we might be dead by the time our packages leave the solar system, at least the ones that we send so far. And if we send something much faster in the future, it will overtake those very slow ships that sail through space. Okay, so after 10 ,000 years, we leave the solar system, we start making our way into, this is truly interstellar space at that point because we cross the midpoint separating us from the nearest star.

59:37Okay. And then to get to the nearest star, we take some more tens of thousands of years because we cross the midpoint. So we're talking tens of maybe 50 ,000 years to reach the nearest star. And that is roughly the time that he lapsed since the first humans left Africa. Okay, just think about it if we were to send a spacecraft when the first humans left Africa, it would get to the nearest star just now. And then if we continue to avoid through space, how long will it take us to go to the other side of the Milky Way Galaxy? That will take us half a billion years. So it sounds long, but it actually is not so long because the time difference between the formation of most stars and the formation of the sun is billions of years, most stars from billions of years before the sun.

1:00:40So there was enough time, even for chemical rockets, to make their way to adore step. But that's a, and at that speed we can't really exit the solar system, as you can tell, because the edge of the solar system is another factor of 10 farther away, and that would make the travel time equal to the age of the universe and you mean the edge not the edge of the soul system the edge of the galaxy you mean. Sorry then yeah the time to cross the age of the Milky Way galaxy would be longer than the age of the universe. Yes okay. And because it's 10 times bigger than the Milky Way disc that I was alluding to before going to a star on the other side of the Milky Way galaxy.

1:01:25So there is the entire hell of dark matter of the Milky Way, which is 10 times bigger, or even more 20 times bigger, than the extent of the disk of stars that are near the center of the Milky Way galaxy. So actually, if you think of galaxies, there is the luminous part, which is sort of like a light bulb in the middle, but then there is this big structure that is invisible to us of dark matter, that is 20 times bigger. What is your proposed propulsion mechanism to get to the nearest closest star at one fifth the speed of light? Oh, that is using a light sail, basically a very thin membrane. That's the concept of the Starship project.

1:02:13If this membrane in ways about a gram if it has the size of a person roughly and it's being pushed by a very powerful laser, a 100 gigawatt laser for a few minutes. It would reach a fifth of the speed of light and you can put in this light cell you can put some electronic infrastructure actually that they could record, for example, take a photograph when it comes close to the planet near Proxima Centauri and also transmit the signal to us. That is not so much of a challenge. The big challenge is generating this photon engine, the radiation that associated with the laser, such that you have a beam of light focused on the sail and pushing it.

1:03:03The sale itself can be made of materials that we already know and that it could be sufficiently tough. The main challenge is getting it to maintain a stable ride on the light beam with a very powerful laser and then communicating whatever it finds near the planet around Proxima Centaurion. And I should say that it takes a few minutes to get it to a fifth of the speed of light. Then it continues the travel like a bullet towards the destination. That will take 20 years at the fifth of the speed of light. So it's two minutes of very fast acceleration and then a coasting over 20 years before it gets to the destination.

1:03:51That's crazy. You need a lot of patience. That's all I'm saying. Well, you need a little bit of patience. You need a lot more accuracy. I think that's the main thing. Yeah, so one of the things that I was thinking about it seems to me It's probably disheartening to hear that you know there isn't going to be a human or it seems unlikely in your estimation that a Human will go to some other system that it's it's likely to be seeded by whatever whatever Well, I would not really tell by the way if you go through the numbers If we develop this technology of light sales and you get to the extreme of using all the energy intercepted by earth from sunlight, you know, and you use all that energy to create a very powerful radio beam that is pushing a giant sail this time.

1:04:42It could propel humans at an acceleration of 1G for about a year and if you accelerate at 1G for one year, you can reach the speed of light. Wow. And that is possible in principle. And we would not feel any different than being on Earth because gravity gives us an acceleration of 1G on the surface of Earth. So if you board a spacecraft that is accelerating at 1G, it would feel just like being on the surface of Earth. And the only issue is how to build the infrastructure necessary to use all the power coming from the sun on earth towards creating a giant radio beam that pushes on a light sail but in principle I did the calculation it's possible.

1:05:35Is there not a second problem which is how do you slow down? Oh for that you need a similar beam on the other end but if you just get to the speed by the way if you board such a ship and you continue accelerating at 1G for 20 years you can cross the entire universe. While the universe is aging, but because of time dilation according to Einstein's special theory of relativity, you can do it in your lifetime. So the only problem there is that you need a huge amount of power to keep accelerating for 20 years at 1G. But I thought you could go quicker than the speed of light. You cannot, well, according to what we know in physics, we cannot go faster than light.

1:06:20But you don't need to, you just need to go very close to the speed of light and then time is ticking more slowly in your spacecraft than it is elsewhere. So the universe, you know, will age by billions of years while you are aging just by a decade. And because you're getting so close to the speed of light, of course, a lot of practical problems, how to get enough power to propel you at 1G for such a long period of time also when you're moving so fast any particle of dust or any material that you collide with will generate a huge explosion on your ship. Yeah, very good. I saw a visual representation, a computer simulation of what it would be like to approach the speed of light from the front deck of a ship, and all manner of weird stuff starts happening.

1:07:11The way that light moves past you and doesn't, it's very, very bizarre. By the way, that is the best way to maintain longevity. When the universe ages by billions of years, you are just aging by decades. Just move fast. Move fast. Yeah, just move fast. And of course, then if you have a similar system elsewhere, you can slow down. The problem is you need someone else to build it. So otherwise, you will just move at that speed for a very long time. Of course, this is science. We are not, I mean, there are practical problems, but it's all allowed by the laws of physics. I don't like science fiction, because it violates the laws of physics, the storyline very often.

1:07:58Avi Loeb, ladies and gentlemen, Avi, I really appreciate your work and very excited to see what you come up with on this new paper, what you can reveal to the world once you've finally got your work done and got it passed everything. And I'm interested to see what other groups of people and colleagues you can pass off as you continue to do your research. Where should people go if they want to keep up to date with all of this stuff that you're talking about and publishing and all the rest of the day? I just wanted to comment on what you said, the footnote, that, you know, we know that we are not at the center of the universe.

1:08:29And we also know that humans came to exist only over the past few million years. So if you come to a play, a cosmic play in this case, you are not at the center of the stage and You're coming at the end of the play the play is not about you and The best way to find out what it's about is to look for other actors and ask them So that's what I'm trying to do in terms of my writings I have essays on medium dot com You can just type avi -lowbethmedium .com where you can find updates about my research. Also, I have a website at Harvard University that you can go to the professional website where you can see some links to papers and videos and interviews and other things.

1:09:17And I have no footprint whatsoever on social media because I just realized that if you want an airplane to fly faster, you reduce the friction with air. You reduce its cross -sectional area. So I reduce my friction to the best of my ability with other people who may criticize me, may want to slow me down. I simply don't have any footprint on social media. Another metaphor that I should mention in this context, there is the metaphor of the crow and the eagle. So the crow is the only bird that can sit on the eagle's back and pick the eagle's neck. And there are photographs of the crow's on the backs of the eagles.

1:10:04But the eagles do not waste any energy or effort pushing the crow's away. What they do is rise to greater heights where the oxygen level is low and the crows just drop off they're back. To me the greatest height is to do my science in the best possible way by collecting evidence, material evidence and studying it and reaching my conclusions based on what the evidence shows and once I get to those heights all the crows that are currently pecking at my neck will drop off. What a make drop. Avie, I really appreciate you. Thank you mate.