1 You’re listening to Imaginary Worlds, a show about how we create them and why we suspend our disbelief. I’m Eric Molinsky. I start every episode by saying that, but I’m always assuming that we are taking a step back from these virtual worlds and examining their relationship to the real world. But what if the real world is an imaginary world? What if we are not real people but virtual people in a computer simulation? That’s been the premise of a gazillion science fiction stories, and many episodes of Black Mirror. But more and more scientists are beginning to wonder if it’s not science fiction. The first person to make that point in 2003 and get people’s attention was Nick Bostrom, who is a professor at Oxford. Other scientists have chimed in, like Neil DeGrasse Tyson, who has said he thinks the odds we’re living in a computer simulation are 50/50. But this idea really went viral when Elon Musk endorsed it in 2016. I’ve been following this debate for a while. I’ve noticed scientists tend to avoid the sci-fi connection because they want to be taken seriously. And sci-fi writers who explore these ideas often don’t want to be tied by down by real science. Then I came across Rizwan Virk, or Riz for short. Riz is the first person I’ve seen who has made science fiction and video games a big part of his argument as to why we’re living in a computer simulation. Riz is a video game designer and a Silicon Valley investor who’s supported game companies like Telltale, and apps like Discord, which began out as a gaming app. He also wrote a book called, “The Simulation Hypothesis.” RIZ: This is a topic I’ve been thinking about for a long time. You know, even when I was a kid, I used to play the video games on the Atari console, like a long time ago, and there would be this racing game. And I remember thinking as we went around the racetrack, you know, what about those people in the bleachers? Are they really real? Are they there after I play the game or not? And so, you know, the idea has been percolating for quite some time, but it was really a few years ago I had sold my last game company and I was visiting a startup that was making a virtual reality ping-pong game. And so I started to play the game and I was in the room with the headset on, you know, at the end of the game, it felt so realistic. The responses for when I hit the ball, uh, the fact that there was this virtual table. So the physics engine was so good that it felt so realistic that at the end of the game, I forgot that I was in virtual reality. And I tried 2 to put the controller down on the table, uh, the paddle down on the table, I thought, and I tried to lean against the table. And of course, I almost fell over and the controller fell to the ground and that's when I realized, oh, you know, someday our virtual reality is going to get so good that we will be unable to distinguish between what's really happening and what's happening in the virtual world. When you’re playing the type of game where you’re exploring a virtual world, the computer only renders what your character can see. The rest of that world is just information, ready to be activated when you show up. RIZ: The same thing with my avatar and your avatar. If we're at the same room, mine is only rendering what I can see in yours is rendering only what you can see, which is a much smaller subset of the actual virtual world, which all exists information. Computer programmers do that to save up energy and hard drive space. One of the unique aspects of Riz’s argument that we’re living in a computer simulation is that he draws the line between how computers render virtual worlds and how quantum physics works. Science was never a strong subject for me in school, but I’ve always been fascinated by quantum physics because when you zoom down into the teeny tiny world that’s smaller than a single atom – those microscopic particles are behaving in ways that feel more like science fiction. For instance, scientists can tell when they’re not observing subatomic particles, these particles are doing crazy things like being in five places at once or disappearing and reappearing. But when scientists focus their microscopes on the particles, the particles suddenly fall in line, like misbehaving students who realize the teacher is watching. I can’t explain how scientist know what’s happening with particles when they’re not observing them, but I know there is math to support this. The big mystery isn’t whether it’s happening but why. Riz has a theory. He says these particles are behaving like pixels a video game, rendering into existence only what we need to see. Maybe that’s because we are in a video game – or a virtual world. Some scientists have argued there's no way a computer could be big enough to render a simulation of our entire planet, let alone the universe. But Riz says anyone who believes that is lacking in imagination. 3 RIZ: Yeah, I think it’s a lack of imagination and, you know, it gets back to the arguments that, you know, back in, I just saw a headline in the, uh, you know, in the New York times that said, uh, from like 1901, I think it was, which wasn't that long ago. When you think about it, that said, you know, man, we'll never build a flying machine. It would take us a million years to get there. Right. And within four years or whatever, it was, somebody had built a flying machine because discovered an optimization technique. What happens in the history of computer science and engineering is that you, you discover tricks, you discover shortcuts, you discover new ways of optimization. In fact, you know, a quantum computer we estimate should be able to break cryptography that say 256 bits long, or 512 bits long. And it turns out that that is more than the number of particles in the universe. So, you could say, well, we could never break that cryptography using a computer because that's, we don't even have that many atoms in the universe turns out a quantum computer shouldn't be able to do it within a decade or so. And so, I just think it's a lack of imagination. So, who is simulating us? RIZ: Well, that's an interesting question, right? And it's one of those big $64,000 $64 million questions. There are two options. First: aliens. Maybe humans went extinct, and this is how aliens are keeping us alive for academic reasons, or they think we’re entertaining. Riz says if we go with that theory, these aliens could be on a planet that’s very different from ours. RIZ: Uh, we don't even know if it's a physical world like ours, right? And some people assume just like in your statement about, well, a computer couldn't be big enough that that physical world is just like our world. Well, we have different physics engines we use inside our games, like in the ping pong game, it was a very realistic physics engine, right. But if you go inside something like Second Life, you know, there's two ways to get to different, different places. The game you can fly, and you can teleport yourself. Well, you can't really do either of those things yet in the physical world. Maybe these aliens are blobs floating around, and they want to experience what it’s like walk on two legs. But I can’t imagine aliens would ever care that much about us to simulate us. The theory which makes more seems to me is that future humans are simulating us, and if you go outside our simulation, it’s actually the year 2625 or something. The first person to propose this theory was Nick Bostrom at Oxford. 4 RIZ: His point was either civilization will not get to the point where they can create realistic simulations. What I call the simulation point. Uh, he said, or they will get there, and they will make no simulations at all. Or the third option is true. And the third option would seem that they get there, and they make lots and lots of simulations. Therefore, there are many more simulated realities than there are physical realities. Therefore, if you exist in a reality, simple statistics, as you are more likely in a simulated reality than base reality, just because there are way more of these than these. Uh, and so that was the art sort of a, more of a philosophical argument, uh, that said basically, if any civilization ever in the universe, whatever the universe is reaches the simulation point, then you are most likely living in a simulation. So, when it would be like us simulating, like the Roman Empire, for example. That already happening with the video game series Assassin’s Creed. The premise of each game is that somebody in the future is sent back in time to live in the body of one of their ancestors so they can fight bad guys.