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 explore the nature of our reality and the future of our civilization. They include Einstein's Cosmos, Physics of the Impossible, Future of the Mind, Parallel Worlds, and his latest, The Future of Humanity: Terraforming Mars, Interstellar Travel, Immortality, and Our Destiny Beyond Earth. I think it's 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 if we're 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, support it on Patreon, or simply connect with me on Twitter @lexfridman, spelled F-R-I-D-M-A-N. 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 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 one-fifth or so of them have Earth-sized planets going around them. So just do the math. We're talking about out of 100 billion stars in the Milky Way galaxy, we're talking about billions of potential Earth-sized planets. And to believe that we're the only one is, I think, rather ridiculous-

(laughs)

... given the odds. And how many galaxies are there? Within sight of the Hubble Space Telescope, there are about 100 billion galaxies. So do the math. How many stars are there in the visible universe? 100 billion galaxies times 100 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, uh, Type 0, 1, 2, 3, 4, and 5 even of the Kardashev scale, um, 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 their I Love Lucy and their Leave It To Beaver, uh, just ordinary day-to-day transmissions that, uh, they emit. And the first thing we wanna do is to, A, decipher their language, of course, but B, 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 we rank stars. That's how we rank civilizations in outer space. So a Type I civilization is capable of harnessing planetary power. They control the weather, for example, earthquakes, volcanoes. They can modify the course of geological events, sort of like Flash Gordon or Buck Rogers.