Michio Kaku: Future of Humans, Aliens, Space Travel & Physics | Lex Fridman Podcast #45

the following is a conversation with Michio Kaku he's a theoretical physicist futurist and professor at the City College of New York he's the author of many fascinating books that explored the nature of our reality and the future of our civilization they include Einsteins cosmos physics of the impossible feature of the mind parallel worlds and his latest the future of humanity terraforming Mars interstellar travel immortality and our destiny beyond earth I think is beautiful and important when a scientific mind can fearlessly explore through conversation subjects just outside of our understanding that to me is where artificial intelligence is today just outside of our understanding a place we have to reach for it for to uncover the mysteries of the human mind and build human level and superhuman level AI systems that transform our world for the better this is the artificial intelligence podcast if you enjoy it subscribe on YouTube give it five stars on iTunes supported on patreon or simply connect with me on Twitter Alex Friedman spelled Fri D M am and now here's my conversation with Michio Kaku you've mentioned that we just might make contact with aliens or at least hear from them within this century can you elaborate on your intuition behind that optimism well this is a pure speculation of course of course but given the fact that we've already identified 4,000 exoplanets orbiting other stars and we have a census of the Milky Way galaxy for the first time we know that on average every single star on average has a planet going around it and about 1/5 or so of them have earth sized planets going around them so just do the math we're talking about out of a hundred billion stars in the Milky Way galaxy we're talking about billions of potential Earth size planets and to believe that we're the only one is I think rather ridiculous given the odds and how many galaxies are there within sight of the Hubble Space Telescope there are about a hundred billion galaxies so do the math how many stars are there in the visible universe a hundred billion galaxies times a hundred billion stars per galaxy we're talking about a number beyond human imagination and to believe that we're the only ones I think is is rather ridiculous so you've talked about different types of types zero one two three four and five even of the car - of scale of the different kind of civilizations do what do you think it takes if it is indeed a ridiculous notion that we're alone in the universe what do you think it takes to reach out first to reach out through communication and connect well first of all we have to understand the level of sophistication of an alien life-form if we make contact with them I think in this century we'll probably pick up signals signals from an extraterrestrial civilization we'll pick up there I Love Lucy and their Leave It to Beaver just ordinary day-to-day transmissions that they emit and the first thing we want to do is to a decipher their language of course but be figure out at what level they are advanced on the Kardashev scale I'm a physicist we rank things by two parameters energy and information that's how we rank black holes that's how you rank stars that's how you rank civilizations in outer space so a type one civilization is capable of harnessing planetary power they control the weather for example earthquakes volcanoes they can modify the course of geologic events sort of like Flash Gordon or Buck Rogers type 2 would be stellar they play with stars entire stars they use the entire energy output of a star sort of like Star Trek the Federation of Planets have colonized the nearby stars so a type 2 would be somewhat similar to Star Trek type 3 would be galactic they roam the Galactic space lanes and type 3 would be like Star Wars a galactic civilization then one day I was giving this talk in London at the planetarium there and the little boy comes up to me and he says professor you're wrong you're wrong this type 4 and I told them look kid there are planets stars and galaxies that's it folks and he kept persisting and saying no there's time for the power of the continuum and I thought about it for a moment and I said to myself is there an extra galactic source of energy the continuum of Star Trek and the answer is yes there could be a type 4 and that's dark energy we now know that 73% of the energy of the universe is dark energy dark matter represents maybe 23 percent or so and we only represent 4% we're the oddballs and so you begin to realize that yeah they could be type 4 maybe even type 5 so type 4 you're saying being able to harness sort of like dark energy something that permeates the entire universe so be able to plug into the entire entire universe is a source of energy that's right and dark energy is the energy of the Big Bang it's why the galaxies are being pushed apart it's the energy of nothing the more nothing you have the more dark energy that's repulsive and so the acceleration of the universe is accelerating because the more you have the more you can have and that of course is by definition and exponential curve it's called a discerner expansion and that's the current state of the universe and then type 5 would that be would that be able to seek energy sources somehow outside of our universe however that idea yeah what time five will be the multiverse multiverse I'm a quantum physicist and we quantum physicists don't believe that the Big Bang happen once that would violate the Heisenberg uncertainty principle and that means that there could be multiple bangs happening all the time even as we speak today universes are being created and that fits the data the inflationary universe is a quantum theory so there's a certain finite probability that universes are being created all the time and for me this is actually rather aesthetically pleasing because you know I was raised as a presbyterian but my parents were Buddhists and there's two diametrically opposed ideas about the universe in Buddhism there's only nirvana there's no beginning there's no end there's only timelessness but in Christianity there is the instant when God said let there be light in other words an instant of creation so I've had these two mutually exclusive ideas in my head and I now realize that it's possible to Mel them into a single theory either the universe had a beginning or it didn't right wrong you see our universe had a beginning our universe had an instant where somebody might have said let there be light but there other bubble universes out there in a bubble bath of universes and that means that these universes are expanding into a dimension beyond our three-dimensional comprehension in other words is hyperspace in other words 11 dimensional hyperspace so Nirvana would be this timeless 11 dimensional hyperspace where big bangs are happening all the time so we can now combine two mutually exclusive theories of creation and Stephen Hawking for example even in his last book even said that this is an argument against the existence of God he said there is no God because there was not enough time for God to create the universe because the Big Bang happened in an instant of time therefore there was no time available for him to create the universe but he see the multiverse idea means that there was a time before time and there multiple times each bubble has its own time and so it means that there could actually be a universe before the beginning of our universe so if you think of a bubble bath when two bubbles collide well when two bubbles fission to create a baby bubble that's called the Big Bang so the Big Bang is nothing but the collision of universes or the budding of universes this is a beautiful picture of our incredibly mysterious existence so is that humbling to you exciting the idea of multiverses I don't even know how to even begin well you wrap my mind around citing for me because what I do for a living is string theory that's my day job I get paid by the city of New York to work on string theory yes and you see string theory is a multiverse theory so people say first of all what is string theory string theory simply says that all the particles we see in nature the electron the proton the quarks what have you or nothing with vibrations on a musical string on a tiny tiny little string you know D Robert Oppenheimer the creator of the atomic bomb was so frustrated in the 1950s with all these subatomic particles being created in our atom smashers that he announced he announced one day that the Nobel Prize in Physics should go to the physicist who does not discover a new particle that year well today we think they're nothing but musical notes on these tiny little vibrating strings so what is physics physics is the harmonies you can write on vibrating strings what is chemistry chemistry is the melodies you can play on these strings what is the universe the universe is a symphony of strings and then what is the mind of God that Albert Einstein's so eloquently wrote about for the last thirty years of his life the mind of God would be cosmic music resonating through eleven dimensional hyperspace so beautifully put what do you think is the mind of Einstein's God do you think there's a way that we could untangle from this from this universe of strings why are we here what is the meaning of it all well Steven Weinberg winner of the Nobel Prize once said that the more we learned about the universe the more we learned that is pointless well I don't know I don't profess to understand the great secrets of the universe however let me say two things about what the Giants of physics have said about this question Einstein believed in two types of God one was the God of the Bible the personal God the God that answers prayers walks on water as performs miracles smites the Philistines that's the personal God that he didn't believe in he believed in the God of Spinoza the God of order simplicity harmony Beauty the universe could have been ugly the universe could have been messy random but it's gorgeous you realize that on a single sheet of paper we can write down all the known laws of the universe it's amazing on one sheet of paper Einstein's equation is one-inch long string theory is a lot longer and so it's a standard model but you could put all these equations on one sheet of paper it didn't have to be that way it could have been messy and so Einstein thought of himself as a young boy entering this huge library for the first time being overwhelmed by the simplicity elegance and beauty of this library but all he could do was read the first page of the first volume well that library is the universe with all sorts of mysterious magical things that we have yet to find and then Galileo was asked about this Galileo said that the purpose of science the purpose of science is to determine how the heavens ago the purpose of religion is to determine how to go to heaven so in other words science is about natural law and religion is about ethics how to be a good person how to go to heaven as long as we keep these two things apart we're in great shape the problem occurs when people from the Natural Sciences begin to pontificate about ethics and people from religion begin to pontificate about natural law that's where we get into big trouble you think they're fundamentally distinct morality and ethics and our our idea of what is right and what is wrong that's something that's outside the reach of string theory in physics that's right if you talk to a squirrel about what is right and what is wrong yes there there's no reference frame for a squirrel and realize that aliens from out of space if they ever come visit us they'll try to talk to us like we talked to squirrels in the forest but eventually we get bored talking to the squirrels because they don't talk back to us same thing with aliens from out of space and they come down to earth they'll be curious about us to a degree but after a while they just get bored because we have nothing to offer them so our sense of right and wrong what does that mean compared to a squirrels sense of right and wrong now we of course do have an ethics that keeps civilizations in line enriches our life and makes civilization possible and I think that's a good thing but it's not mandated by a law of physics so if aliens do alien species were to make contact forgive me for staying on aliens for a bit longer do you think they're more likely to be friendly to befriend us or to destroy us well I think for the most part our they'll pretty much ignore us if you were deer in the forest who do you fear the most do fear the hunter with his gigantic 16 gauge shotgun or do you fear the guy with a briefcase and glasses well the guy with a briefcase could be a developer about to basically flatten the entire forest destroying your livelihood so instinctively you may be afraid of the hunter but actually the problem with deers in the forest is that they should fear developers in developing because developers look at deer as simply getting in the way I mean in war the world's by hto wells the aliens did not hate us if you read the book the aliens did not have evil intentions toward him Homo sapiens no we were in the way so I think we have to realize that alien civilizations made viewers quite differently than in science fiction novels however I personally believe and I cannot prove any of this I personally believe that they're probably going to be peaceful because there's nothing that they want from our world I mean what are they gonna kick us what are they gonna take us for gold no gold is a useless metal for the most part it's silver I mean is gold golden color but that only affects Homo sapiens squirrels don't care about gold and so gold is a rather useless element rare earths may be platinum-based elements rare earths for their electronics yeah maybe but other than that we have nothing to offer them I mean think about it for a moment people love Shakespeare and they love the arts and poetry but outside of the earth they mean nothing absolutely nothing I mean when I write down an equation in string theory I would hope that on the other side of the galaxy there's an alien writing down that very same equation in different notation but that alien on the other side of the galaxy Shakespeare poetry Hemingway it would be nothing to him or her or it when you think about entities that's out there extraterrestrial do you think they would naturally look something that even is recognizable to us as his life or can it would they be radically different well how did we become intelligent basically three things made us intelligent one is our eyesight stereo eyesight we have the eyes of a hunter stereo emissions will be lock-in on targets and and who is smarter predator or prey predators are smarter than prey they have their eyes at the front of their face like lions tigers wild rabbits have eyes to the side of their face why is that hunters have to zero in on the target they have to know how to ambush they have to know how to hide camouflage sneak up stealth deceit that takes a lot of intelligence rabbits all they have to do is run so that's the first criterion stereo eyesight of some sort second is the thumb the opposable thumb of some sort could be a claw or tentacle so a hand-eye coordination and eye coordination is the way we manipulate the environment and then three language because you know mama bear never tells baby bear to avoid the human hunter bears just learned by themselves they never hand on information from one generation to the next so these are the three basic ingredients of intelligence eyesight of some sort an opposable thumb or tentacle or claw of some sort and language now ask yourself a simple question how many animals have all three just us it's just us I mean the primates they have a language yeah they may get up to maybe 20 words but a baby learns a word-a-day several words a day a baby learns and a typical adult knows about almost 5,000 words while the maximum number words that you can teach a gorilla in any language including their own language is about 20 or so and so we see the difference in intelligence so when we meet aliens from outer space chances are they will have been descended from predators of some sort they'll have some way to manipulate the environment and communicate their knowledge to the next generation that's it folks so functionally that would that would be similar they would we would be able to recognize them well not necessarily because I think even with Homo sapiens we are eventually going to perhaps become part cybernetic and genetically enhanced already robots are getting smarter and smarter right now robots have the intelligence of a cockroach but in the coming years our robots will be as smart as a mouse then maybe as smart as a rabbit if we're lucky maybe as smart as a cat or a dog and by the end of the century who knows for sure our robots will be probably as smart as a monkey now at that point of course they could be dangerous you see monkeys are self-aware they know they are monkeys they may have a different agenda than us while dogs dogs are confused you see dogs think that we are a dog that we're the top dog they're the underdog that's why they whimper and follow us and lick us all the time for the top dog monkeys have no illusion at all they know who we are not monkeys and so I think that in the future we'll have to put a chip in their brain to shut them off once our robots have murderous thoughts but that's in a hundred years in 200 years the robots will be smart enough to remove that failsafe chip in their brain and then watch out at that point I think rather than compete with our robots we should merge with them we should become part cybernetic so I think we'll be beat alien life from outer space they may be genetically and and cybernetically enhanced genetically and cybernetically enhanced Wow so let's talk about that full range in the near term and 200 years from now how promising in the near term in your view is brain machine interfaces those starting to allow computers to talk directly to the brains Elon Musk is working on that with neural link and there's other companies working on this idea do you see promise there do you see hope for near-term impact well every technology has pluses and minuses already we can be core memories I have a book the future of the mine or I detail some of these breakthroughs we can now record simple memories of mice and send these memories on the Internet eventually we're going to do this with primates at Wake Forest University and also in Los Angeles and then after that we'll have a memory chip for Alzheimer's patients well test it out in alzheimerís patients because of course when Alzheimer is patients lose their memory they wander they create all sorts of havoc wandering around oblivious to their surroundings and they'll have a chip they'll push the button and memories memories will come flooding into their hippocampus and the chip telling them where they live and who they are and so a memory chip is definitely in the cards and I think this will eventually affect human civilization what is the future of the Internet the future of the Internet is brain net brain net is when we send emotions feelings sensations on the internet and we will telepathically communicate with other humans this way this is gonna affect everything look at entertainment remember the silent movies a Charlie Chaplin was very famous during the era of silent movies but when the talkies came in nobody wanted to see Charlie Chaplin anymore because he never talked in the movies and so a whole generation of actors lost their job and a new series of actors came in next we're gonna have the movies replaced by rain net because in the future people will say who wants to see a screen with images that's it sound an image that's called the movies yeah our entertainment industry this multi-billion dollar industry is based on screens with moving images and sound but what happens when emotions feelings sensations memories can be conveyed on the Internet it's going to change everything human relations will change because you'll be able to empathize and feel the suffering of other people will be able to communicate telepathically and this is this is coming you describe brain that in feature of the mind this is an interesting concept do you think so you mentioned entertainment but what kind of effect would it have on our personal relationships hopefully it will deepen it you realize that for most of human history for over 90% of human history we only knew maybe 20 a hundred people yeah that's it folks that was your tribe that was everybody you knew in the universe was only maybe 50 or a hundred with the coming of towns of course it expanded to a few thousand with the coming of the telephone all of a sudden you could reach thousands of people with a telephone and now with the internet you can reach the entire population of the planet Earth and so I think this is a normal progression and you you think that kind of sort of connection to the rest of the world and then adding sensations like being able to share telepathically emotions and so on that would just further deepen our connection to our fellow humans yes right in fact I disagree with many scientists on this question most scientists would say that technology is neutral a double-edged sword one sword one side of the sword can cut against people the other side of the sword can cut against ignorance and disease I disagree I think technology does have a moral direction look at the Internet the internet spreads knowledge awareness and that creates empowerment people act on knowledge when they begin to realize that they don't have to live that way they don't have to suffer under a dictatorship that there are other ways of living under freedom then they begin to take things take power and that spreads democracy and democracies do not war with other democracies I'm a scientist I believe in data so let's take a sheet of paper and write down every single war you had to learn since you were an elementary school every single war hundreds of kings queens emperors dictators all these wars were between kings queens emperors and dictators never between two major democracies and so I think with the spread of this technology and which would accelerate with the coming of brain net it means that well we will still have wars wars of course as politics by other means but there'll be less intense and less frequent do you have worries of longer-term existential risk from technology from AI so I think that's a wonderful vision of a future where war is a distant memory but now there's another agent there's there's there's somebody else that's able to create conflict that's able to create harm AI systems so do you have worry about such AI systems well yes that is an existential risk but again I think an existential risk not for this century I think our grandkids are gonna have to confront this question as robots gradually approach the intelligence of a dog a cat and finally that of a monkey however I think we will digitize ourselves as well not only are we gonna merge with our technology it will also digitize our personality our memories our feelings you realize who did during the Middle Ages there was something called dualism dualism meant that the soul was separate from the body when the body died the soul went to heaven that's dualism then in the 20th century neuroscience came in and said bah humbug every time we look at the brain it's just neurons that's it folks period end of story bunch of neurons firing now we're going back to dualism now we realize that we can digitize human memories feelings sensations and create a digital copy of ourselves and that's called the connectome project billions of dollars are now being spent to do not just the genome project of sequencing the genes of our body but the connectome project which is to map the entire connections of the human brain and even before then already in Silicon Valley today at this very moment you can contact Silicon Valley companies that are willing to digitize your relatives because some people want to talk to their parents there are unresolved issues with their parents and one day yes firms will digitize people and you'll be able to talk to them a reasonable facsimile we Lea we leave a digital trail our ancestors did not our ancestors were lucky if they had one line just one line in a church book saying the day they were baptized and the day they died that's it that was their entire digital memory I mean their entire digital existence summarized in just a few letters of the alphabet a whole life now we digitized everything every time you sneeze you digitized it you put it on the Internet and so I think that we are going to digitize ourselves and give us digital immortality will not only have biologic genetic immortality of some sort but also digital immortality and what are we going to do with it I think we should send it into outer space if you digitize the human brain and put it on a laser beam and shoot it to the moon you're on the moon in one second shoot it to Mars you're on Mars in 20 minutes shoot it to Pluto you're on Pluto in eight hours think about it for a moment you can have breakfast in New York and for a morning snack vacation on the moon then zap your way to Mars by noontime journey through the asteroid belt of the afternoon and they come back for dinner in New York at night all in a day's work it's at the speed of light now this means that you don't need booster rockets you don't need weightlessness problems you don't need to worry about meteorites and what's on the moon on the moon there is a mainframe that downloads your laser beams information and where does it download the information into an avatar now what does it ever try look like anything you want yeah think about it for a moment you could be Superman superwoman on the moon on Mars traveling throughout the universe at the speed of light downloading your personality into any vehicle you want now let me stick my neck out so for everything I've been saying is well within the laws of physics well within the laws of physics now let me go outside the laws of physics here we go I think this already exists I think outside the earth there could be a superhighway a laser highway of laser pointing with billions of souls of aliens zapping their way across the galaxy now let me ask you a question are we smart enough to determine whether such a thing exists or not no this could exist right outside the orbit of the planet Earth and we're too stupid in our technology to even prove it or disprove it we would need the aliens on this laser superhighway to help us out just to send us a human interpretable signal I mean it ultimately boils down to the language of communication but that's an exciting possibility that actually the sky is filled with aliens should already be here and we're just so oblivious that we're too stupid to know it see they don't have to be an alien form with with little green men they could be in any form they want in an avatar of their creation or in fact they could very well be they look like us exactly he'd never know one of us could be an alien you know in a zoo did you know that we sometimes have zookeepers that imitate animals we create a fake animal and we put it in so that the animal is not afraid of this fake animal and of course these animals brains their brain is about as big as a walnut they accept these dummies as if they were real so an alien civilization in outer space would say oh yeah human brains are so tiny we could put a dummy on their world and avatar and they never know it that would be an entertaining thing to watch from the alien perspective so you kind of implied that with it was a digital form of our being but also biologically do you think one day technology will allow individual human beings to become immortal besides just through the ability to digitize our essence yeah I think that artificial intelligence will give us the key to to genetic immortality you see in the coming decades everyone's going to have their gene sequence will have billions of genomes of old people billions of genomes of young people and what are we going to do with it we're gonna run into an AI machine which has a pattern recognition to look for the Aged genes in other words the Fountain of Youth that Emperor's kings and queens lusted a ver over the Fountain of Youth will be found by artificial intelligence artificial intelligence will identify where these aged genes are located first of all what is aging we now know what aging is aging is the build-up of errors that's all aging is the buildup of genetic errors this means that cells eventually become slower sluggish if they go into senescence and they die in fact that's why we die we die because of the build up of mistakes in our genome in our cellular activity but you've seen the future we'll be able to fix those genes with CRISPR type technologies and perhaps even live forever so let me ask you a question we're just aging take place in a car given a car where does aging take place well it's obvious the engine right a that's where you have a lot of moving parts B that's where you have combustion well where in the cell do we have combustion the mitochondria we know know where ageing takes place and if we cure many of the mistakes that build up in the mitochondria of the cell we could become immortal let me ask you if you self could become immortal would you damn straight now I think about it for a while because of course if the term it depends on how you become immortal you know there's a famous myth of Tiffany's it turns out that years ago the in the Greek mythology there was the saga of Tiffany's and Aurora Aurora was the goddess of the dawn and she fell in love with a mortal a human called Athena's and so Aurora begged big Zeus to grant her the the gift of immortality to give to her lover so Zeus took pity on Aurora and made Tiffany's immortal but you see Aurora made a mistake a huge mistake she asked for immortality but she forgot to ask for eternal youth so port Athena's got older and older and older every year decrepit a bag of bones but he could never die never done quality of life is important so I think immortality is a great idea as long as you also have immortal youth as well now I personally believe and I cannot prove this but I personally believe that our grandkids may have the option of reaching the age of 30 and then stopping they may like being age 30 is you have wisdom you have all the benefits of age and maturity and you still live forever with a healthy body our descendants may like being 30 for several centuries is there an aspect of human existence that is meaningful only because we're mortal well every waking moment we don't think about it this way but every waking moment actually we are aware of our death and our mortality think about it for a moment when you go to college you realize that you're in a period of time where soon you will reach middle age and have a career and after that you'll retire and then you'll die and so even as a youth even as a child without even thinking about it you are aware of your own death because it sets limits to your lifespan I got a graduate from high school I got a graduate from college why because you're gonna die because unless you graduate from high school unless you graduate from college you're not gonna enter old age with enough money to retire and then die and so yeah people think about it unconsciously because it affects every aspect of your being the fact that you go to high school college get married have kids miss a clock a clock ticking even without your permission it gives a sense of urgency do you do you yourself I mean there's so much excitement and passion in the way you talk about physics and we talk about technology in the future do you yourself meditate on your own mortality do you think about this clock that's ticking well I try not to because it begins to affect your behavior you begin to alter your behavior to to match your expectation of when you're gonna die so let's talk about youth and then let's talk about death okay when I interview scientists on radio I often ask them what made the difference how old were you what changed your life and they always say more or less the same thing no these are Nobel Prize winners directors of major laboratories very distinguished scientists they always say when I was 10 when I was 10 something happened it was a visit to the planetarium it was the telescope for Steven Weinberg winner of the Nobel Prize it was the chemistry kid for Heinz piggles it was a visitor to the planetarium for Isidor Rabi it was a book what the planets for Albert Einstein it was a compass something happened which gives them this existential shock because you see before the age of 10 everything is mommy and daddy mommy and dad that's your universe maja me and daddy around the age of 10 you begin to wonder what's beyond me and daddy and that's when you have this epiphany when you realize oh my god there's a universe out there a universe of discovery that sensation stays with you for the rest of your life you still remember that shock that you felt gazing at the universe and then you hit the greatest destroyer of scientists known to science the greatest destroyer of scientists known to science is junior high school we knew hit junior high school folks it's all over yeah it's all over because in junior high school people say hey stupid I mean you like that nerdy stuff and your friends shun you all of a sudden you people think you're a weirdo and scientists made boring you know Richard Feynman the Nobel Prize winner when he was a child his father would take him into the forest and the father would teach him everything about birds why do you shape the way they are their wings the coloration the shape of their beak everything about birds so one day a bully comes up to the future Nobel Prize winner and says hey dick what's the name of that bird over there well he didn't know he knew everything about that bird except his name so he said I don't know and then the bully said what's the matter dick you stupid or something and then in that instant he got it he got it he realized that for most people science is giving names to birds that's what science is you know lots of names of obscure things Hey people say you're smart you're smart you know all the names of the dinosaurs you know all the names of the plants no that's not science at all science is about principles concepts physical pictures that's what science is all about my favorite quote from Einstein is that unless you can explain a theory to a child the theory is probably worthless meaning that all great theories are not big words all great theories are simple concepts principles basic physical pictures our relativity is all about clocks meter sticks rocket ships and locomotives Newton's laws of gravity are all about balls and spinning wheels and things like that that's what physics and science is all about not memorizing things and that stays with you for the rest of your life so even in old age I've noticed that these scientists when they sit back they still remember they still remember that flush that flush of excitement they felt with that first telescope that first moment when they encountered the universe that keeps them going that keeps them going by the way I should point out that when I was 8 something happened to me as well when I was 8 years old it was in all the papers that a great scientist had just died and they put a picture of his desk on the front page that's it just a simple picture of the front page of the newspapers of his desk that desk had a book on it which was opened and the caption said more or less this is the unfinished manuscript from the greatest scientists of our time so I said to myself well why couldn't you finish it what's so hard that you can't finish it if you're a great scientist it's a homework problem right you go home you solve it or you ask your mom why couldn't he solve it so to me this was a murder mystery this was greater than any adventure story I had to know why the greatest scientists of our time couldn't finish something and then over the years I found out the guy had a name Albert Einstein and that book was the theory of everything it was unfinished well today I can read that book I can see all the dead ends and false starts that he made and I began to realize that he lost his way because he didn't have a physical picture to guide him on the 3rd try on the first try he talked about clocks and lightning bolts and meter sticks and they gave us special relativity which gave us the atomic bomb the second great picture was gravity with balls rolling on curved surfaces and they gave us the big bang creation of the universe black holes on the third try he missed it he had no picture at all to guide him in fact there's a quote I have where he said I'm still looking I'm still looking for that picture he never found it well today we think that picture is string theory the string theory can unify gravity and this mysterious thing that ice tide didn't like which is mechanics Oh couldn't couldn't quite pin down and make sense of that's right mother nature has two hands the left hand and a right hand the left hand is a theory of the small the right hand is a theory of the big the theory the small is the quantum theory the theory of atoms and quarks the theory of the big is relativity the theory of black holes big bangs the problem is the left hand does not talk to the right hand they hate each other the left hand is based on discrete particles the right hand is based on flute smooth surfaces how do you put these two things together into a single theory they hate each other the greatest minds of our time the greatest minds of our time worked on this problem and failed today the only one the only theory that has survived every challenge so far is string theory that doesn't mean string theory is correct it could very well be wrong but right now is the only game in town some people come up to me and say professor I don't believe in the string theory give me an alternative and I tell them there is none get used to it it's the best theory we got it's the only theory we have it's the only theory we have do you see you know the strings kind of inspire a view as did atoms and particles and quarks but especially strings inspire view of a universe as a kind of information processing system as a as a computer of sorts do you see the universe in this way no some people think in fact the whole universe is a computer of some sort yes and they believe that perhaps everything therefore is a simulation yes I don't think so I don't think that there is a super video game where we are nothing but puppets dancing on the screen and somebody hit the play button and here we are talking about simulations no even Newtonian mechanics says that the weather the simple weather is so complicated with trillions upon trillions of atoms that it cannot be simulated in a find out an amount of time in other words the smallest object which can describe the weather and simulate the weather is the weather itself the smallest object that can simulate a human is the human itself and if you had quantum mechanics it becomes almost impossible to simulate it with a conventional computer is quantum mechanics deals with all possible universes parallel universes a multiverse of universes and so the calculation just spirals out of control now they're at so far there's only one way where you might be able to argue that the universe is a simulation and this is still being debated by quantum physicists it turns out that if you throw the Encyclopedia into a black hole the information is not lost eventually it winds up on the surface of the black hole now the surface of the what I call is finite in fact you can calculate the maximum amount of information you can store in a black hole it's a finite number it's a calculable number believe it or not now if the universe were made out of black holes which is the maximum universe you can conceive of each universe each black hole has a finite amount of information therefore our go that uh our go the total amount of information in a universe is finite this is mind-boggling this I consider mind-boggling that all possible universes are countable and all possible universes can be summarized in a number a number you can write on a sheet of paper all possible universes and it's a finite number now is huge it's a number beyond human imagination it's a number based on what is called the Planck length but it's a number and so if a computer could ever simulate that number then it would the universe would be a simulation so theoretically because it's because the amount of information is finite there well there necessarily must be able to exist a computer it's just from an engineering perspective maybe impossible to be yes so no computer can build a universe capable of simulating the entire universe except the universe itself so that's your intuition that our universe is very efficient and so there's no shortcuts right - two reasons why I believe the universe is not a simulation first the calculational numbers are just incredible no finite the Turing machine can simulate the universe and second why would any super intelligent being simulate humans if you think about it most humans are kind of stupid I mean we do all sorts of crazy stupid things right and we call it art we call it humor we call it human civilization so why should an advanced civilization go through all that effort just to simulate Saturday Night Live well that's a funny idea it's also do you think it's possible that the act of creation cannot anticipate humans you simply set the initial conditions and set a bunch of physical laws and just for the fun of it see what happens you'll launch the thing so you're not necessarily simulating everything you're not simulating every little bit in in the same in the sense that you could predict what's going to happen but you set the initial conditions set the laws and see what kind of fun stuff happens well some in some sense that's how life got started in the 1950s Stanley did what is called the Miller experiment he put a bunch of hydrogen gas methane toxic gases with liquid and a spark in a small glass beaker and then he just walked away for a few weeks came back a few weeks later and bingo out of nothing in chaos came amino acids if he had left it there for a few years he might have gotten protein protein molecules for free that's probably how life got started as a accident and if he had left it there for perhaps a few million years DNA might have formed in that beaker and so we think that yeah DNA life all that could have been an accident if you wait long enough and remember our universe is roughly 13.8 billion years old that's plenty of time for lots of random things to happen including life itself yeah we could be just a beautiful little random moment and there could be a nearly infinite number of those in throughout the history of the universe many many creatures like us we perhaps are not the epitome of what the universe is created for her thank God let's hope not just look around yeah you're right what do you think the first human will step foot on Mars I think it's a good chance in 2030s that we will be on Mars in fact there's no physics reason why we can't do it it's an engineering problem it's a very difficult and dangerous engineering problem but it is an engineering problem and in my book future of humanity I even speculate beyond that that by the end of the century we'll probably have the first starships the first starships will not look like the enterprise at all they'll probably be small computer chips that are fired by laser beams with parachutes and like what Stephen Hawking advocated the breakthrough starshot program could send ships ship to the nearby stars traveling at 20% of speed of light reaching Alpha Centauri in about 20 years time beyond that we should have fusion power using power is in some sense one of the ultimate sources of energy but it's unstable and we don't have fusion power today now why is that first of all stars for mammals for free you get a bunch of gas large enough it becomes a star I mean you didn't have to do anything to it and it becomes a star why is fusion so difficult to put on the earth because you're not a space stars our mana poles they are pole single poles that sphere are there a spherically symmetric and it's very easy to get spherical symmetric configurations of gas to compress into a star he just happens naturally all by itself the problem is magnetism is bipolar you have a North Pole and a South Pole and it's like trying to squeeze a long balloon take a long balloon and trying to squeeze it you squeeze one side it bulges out the other side well that's the problem with fusion machines we use magnetism with the North Pole in the South Pole to squeeze gas and all sorts of anomalies and horrible configurations can take place because we're not squeezing something uniformly like in a star stars in some sense or for free fusion on the earth is very difficult but I think it's inevitable and it'll eventually gave us unlimited power from seawater so seawater will be the ultimate source of energy for the planet Earth why what's the intuition there because we'll extract hydrogen from seawater burn hydrogen in the fusion reactor to get give us unlimited energy without the meltdown without the nuclear waste why do we have meltdowns we have meltdowns because in the fission reactors every time you split the uranium atom you get nuclear waste tons of it 30 tons of nuclear waste per reactor per year and it's hot it's hot for thousands millions of years that's why we have meltdowns but you see the waste product of a fusion reactor is helium gas helium gas is actually commercially valuable you can make money selling helium gas and so the waste product of a fusion reactor is helium not nuclear waste that we find in a commercial fission plant in that controlling mastering controlling fusion allows us to converse us into a type 1 I guess civilization right yeah probably the backbone of a type one civilization will be fusion power we by the way are type zero we don't even rate on this scale we get our energy from dead plants for God's sake oil and coal but we are about a hundred years from being type one you know get a calculator in fact Carl Sagan calculated that we are about 0.7 fairly close to a 1.0 for example what is the internet the Internet is the beginning of the first type one technology to enter into our century the first planetary technology is the Internet what is the language of type 1 on the internet already English and Mandarin Chinese are the most dominant languages on the Internet and what about the culture we're seeing a type 1 Sports soccer the Olympics a type 1 music a youth culture rock and roll rap music type 1 fashion Gucci Chanel a type 1 economy the European Union NAFTA what have you so we're beginning to see the the beginnings of a type 1 culture in a type one civilization and inevitably it will spread beyond this planet so you talked about sending at 20% the speed of light on a chip into Alpha Centauri but in a slightly nearer term what do you think about the idea when we still have to send biological our biological bodies the colonization of planets colonization of Mars DC is becoming a two-planet species ever or any time soon well just remember the dinosaurs did not have a space program now and that's why they're not here today how come there are no dinosaurs in this room today because they didn't have a space program we do have a space program which means that we have an insurance policy now I don't think we should bankrupt the earth or deplete the earth to go to Mars that's too expensive and not practical but we need a settlement a settlement on Mars in case something bad happens to the planet Earth and that means we have to terraform Mars now to terraform Mars if we get raised a temperature of Mars by 6 degrees 6 degrees then the polar icecaps begin to melt releasing water vapor water vapor is the greenhouse gas it causes even more melting of the ice caps so it becomes a self-fulfilling see it feeds on itself it becomes autocatalytic and so once you hit six degrees were rising of the temperature on Mars by six degrees it takes off and we melt the polar ice caps and liquid water once again flows in the rivers the canals are the channels and the oceans of Mars Mars once had an ocean we think about the size of the United States and so that is a possibility now how do we get there how do we raise the temperature of Mars by six degrees Elon Musk would like it didn't a hydrogen warheads on the polar icecaps yes well I'm not sure about that because we don't know that much about the effects of detonating hydrogen warheads to melt the polar ice caps and who wants to glow in the dark at night reading the newspaper so I think there are other ways to do it with solar satellites you can have satellites orbiting Mars that beam sunlight onto the polar ice caps melting the polar ice caps Mars has plenty of water it's just frozen I think you paint and inspiring in a wonderful picture of the future it's I think you've inspired and educated thousands if not millions Michio it's been an honor thank you so much for talking today my pleasure you

Channel: Lex Fridman

Views: 1,633,572

Rating: 4.7848158 out of 5

Keywords:

Id: kD5yc1LQrpQ

Length: 61min 0sec (3660 seconds)

Published: Tue Oct 22 2019

Reddit Comments

[u/alexdevero]

Outline:

0:00 - Introduction

1:14 - Contact with Aliens in the 21st century

6:36 - Multiverse and Nirvana

9:46 - String Theory

11:07 - Einstein's God

15:01 - Would aliens hurt us?

17:34 - What would aliens look like?

22:13 - Brain-machine interfaces

27:35 - Existential risk from AI

30:22 - Digital immortality

34:02 - Biological immortality

37:42 - Does mortality give meaning?

43:42 - String theory

47:16 - Universe as a computer and a simulation

53:16 - First human on Mars

[u/SupportVectorMachine]

Although I respect the guy, Michio Kaku is ridiculously overexposed and opines on far too many things outside of his wheelhouse.

[u/Arminas]

Lex Fridman has such a great podcast, I was so excited when I saw Michio Kaku in my recommendations this morning

[u/akilaanxious]

Intriguing.

And everyone should heed what he's saying.

He would be the relevant generation's George Orwell and Aldous Huxley

Today, both sides of the political aisle bring up 1984

People of the future will bring up Michio Kaku.

It may seem funny now, what he's saying about predatory aliens and robots with murderous thoughts, but it comes from insight deep thinking even if dismissed for surface reasons today.