Speaker 1: Hi, Welcome to Science Stuff, a production of iHeartRadio. My
Speaker 1: name is Jorge cham and today we're asking the question
Speaker 1: are we living in a simulation? Are you and I
Speaker 1: real people? Or are we characters in a fake video
Speaker 1: game put on by an advanced alien civilization. Believe it
Speaker 1: or not, this is a possibility that is actually being
Speaker 1: considered and discussed by really smart philosophers and scientists. We're
Speaker 1: going to talk to the man who first proposed this
Speaker 1: philosophical argument, and we'll talk to a quantum information scientist
Speaker 1: who thinks he knows how to tell if we're living
Speaker 1: in a computer or not. So whether you're simulated or real,
Speaker 1: join us as we break the code and answer the
Speaker 1: question are we living in a simulation?
Speaker 2: Hi?
Speaker 1: Everyone, Okay, we're going to do something different today, and
Speaker 1: that is we're going to give you a choice. In
Speaker 1: this episode, there's an argument that none of this and
Speaker 1: none of us us are real. But as Morphius said
Speaker 1: in the Matrix movies, not everyone is ready to hear
Speaker 1: the truth. So we're going to offer you a red
Speaker 1: pill and a blue pill. If you take the red pill,
Speaker 1: you will hear the argument for the idea that we're
Speaker 1: living in a simulation, and if you're convinced, as many
Speaker 1: smart people are, it's going to turn your world upside down.
Speaker 1: But if you take the blue pill, then you'll hear
Speaker 1: the argument against the idea we're all living in a simulation,
Speaker 1: and you can go back to the life you've been living,
Speaker 1: even if it's all a lie. And then later on
Speaker 1: we're going to offer you a third pill, a purple pill,
Speaker 1: but that's going to come later. So here's your choice
Speaker 1: for now. To take the red pill, skip to the
Speaker 1: next chapter and hopefully your podcast player recognizes chapter markers,
Speaker 1: or just keep listening and you'll hear why some scholars
Speaker 1: think we're living inside a computer. Or to take the
Speaker 1: blue pill and be reassured you're a real person. Kip
Speaker 1: ahead two chapters. We go to after the first ad
Speaker 1: break at about the middle of the episode, and you'll
Speaker 1: jump straight to the argument against the idea we're living
Speaker 1: in a simulation. All right, pause the episode if you
Speaker 1: have to. I'll give you a second to make your choice,
Speaker 1: And here we go the red pill, Why we are
Speaker 1: probably living in a simulation. One of the first mentions
Speaker 1: of this idea is in a nineteen sixty four science
Speaker 1: fiction novel called Simulacron three. In the book, a man
Speaker 1: named Douglas Hall helps create a computer simulation of a
Speaker 1: city filled with simulated people who think they are real
Speaker 1: people as a platform to do marketing research. But when
Speaker 1: strange events happen to him and his coworkers, he starts
Speaker 1: to realize that he is living in a computer simulation.
Speaker 1: He's a computer program and the simulation he was working
Speaker 1: on is a simulation inside of another simulation. But the
Speaker 1: reason this idea has been so talked about in recent
Speaker 1: years is due to a man named Nick Bostrom. Doctor
Speaker 1: Boston is a philosopher and former professor at Oxford University
Speaker 1: who published the paper in the Philosophical Quarterly in two
Speaker 1: thousand and three titled Are We Living in a Computer Simulation?
Speaker 1: In which he presented his argument that the most rational
Speaker 1: thing for humans to do is to assume that we
Speaker 1: are living in a simulation created by an advanced species
Speaker 1: of humans or aliens. The argument is so persuasive that
Speaker 1: it's been hotly debated for the last twenty years. Of
Speaker 1: this argument, Neil Degrassi Tyson, the famous astrophysicist, said, quote,
Speaker 1: I wish I had a good argument against that, but
Speaker 1: I do not end quote, even he is partially convinced. Okay,
Speaker 1: so what is this argument? To find out, I went
Speaker 1: straight to the source and talked to doctor Nick Bostrom.
Speaker 1: Thank you doctor Boston for joining us here today could
Speaker 1: be with George. Can you please tell us who you
Speaker 1: are and what do you do.
Speaker 2: I'm a Nick Bostrom, I'm a philosopher. Have been thinking
Speaker 2: for a long time about the future of technology AI
Speaker 2: in particular, and the implications for the big picture situation
Speaker 2: for humanity.
Speaker 1: So for those of us that are not familiar, what
Speaker 1: is the simulation?
Speaker 2: Well, in the context of the simulation argument, which I
Speaker 2: published back in two thousand and one, a simulation refers
Speaker 2: to a detailed computer simulation run by some technologically advanced civilization,
Speaker 2: which includes brains, simulations of brains simulated at the sufficient
Speaker 2: level of detail that these simulated brains are conscious and
Speaker 2: have experiences similar to the experiences that we have. It's
Speaker 2: a computer program, Yeah, an implementation of a computer program. Okay,
Speaker 2: here's the scenario. Imagine a computer the size of a planet,
Speaker 2: and this giant computer is running a computer program that's
Speaker 2: simulating a virtual world in which you, you, me, and
Speaker 2: everyone you know is not real, which is part of
Speaker 2: the simulation. So you don't really have a brain. Your
Speaker 2: brain is just code being simulated inside the program. And
Speaker 2: this program is being run by a super advanced civilization,
Speaker 2: which could be humans in the future, or it could
Speaker 2: be aliens. Yes, it's a wild scenario. So what could
Speaker 2: possibly make us think it's true? Now you've famously said
Speaker 2: that there's an argument to be made that we are
Speaker 2: currently living in a simulation. What is that argument? The
Speaker 2: simulation argument argues that one of three possibilities is true.
Speaker 2: The first possibility is that almost all civilizations at our
Speaker 2: current stage of technological development go extinct before they reach
Speaker 2: technological maturity. The second possibility is that out of all
Speaker 2: civilizations throughout the universe or the multiverse that do reach
Speaker 2: technolgical maturity, a strong convergence in that they all basically
Speaker 2: all of them lose interest in creating ancestors simulations.
Speaker 1: All right, The argument for the idea that we're living
Speaker 1: in a simulation comes down to three possibilities about the universe.
Speaker 1: The first possibility is that most civilizations in the universe
Speaker 1: snuff themselves out before they become the kind of super
Speaker 1: advanced species that can create these massive simulations. This would
Speaker 1: imply that there are no advanced civilizations in the universe
Speaker 1: and there never will be, because none of them ever
Speaker 1: make it that far. Maybe they wipe themselves out with
Speaker 1: nuclear war or environmental disaster, or maybe they deplete all
Speaker 1: their resources, or maybe bad luck just catches up to
Speaker 1: them and an asteroid or a comet eventually kills them.
Speaker 1: The second possibility is that there are civilizations that do
Speaker 1: become super advanced, to the point where they have nearly
Speaker 1: infinite resources, and they could make these massive planet sized similations,
Speaker 1: but for some reason they don't. Maybe they'll think it's
Speaker 1: a waste of time, or they find it morally objectionable
Speaker 1: to create sentient beings. And then there's a third possibility.
Speaker 2: And then the third remaining possibility is suppose it's not
Speaker 2: the case that almost all civilizations fail to reach technolgical maturity,
Speaker 2: so that means that like some significant fraction of them
Speaker 2: get through. Then let's suppose that at least some non
Speaker 2: trivial fraction of these civilizations that do become technolgically mature
Speaker 2: are still interested in using some non negligible fraction of
Speaker 2: the resources for this purpose of creating simulations. You can
Speaker 2: then show that there would be many, many more people
Speaker 2: like us living inside simulations than that would be people
Speaker 2: like us living in the original history. Because even using
Speaker 2: a small fraction of the resources of a technolically advanced civilization,
Speaker 2: you could run millions and millions and millions simulations of
Speaker 2: all of human history. Then it would be the case
Speaker 2: that most people like us would be in simulations, the
Speaker 2: overwhelming majority.
Speaker 1: Okay, here's the core of the argument. It's basically a
Speaker 1: betting argument. If the other two possibilities are not true,
Speaker 1: meaning that there are advanced civilizations out there and at
Speaker 1: least some of them think it's cool to create massive,
Speaker 1: planet sized computer simulations, then the odds are that we
Speaker 1: are in one of those simulations. That is because these
Speaker 1: advance civilizations, doctor Boston argues wouldn't just create one simulation,
Speaker 1: they would create millions of them.
Speaker 2: Just like when.
Speaker 1: Millions of kids here on Earth play say Minecraft, each
Speaker 1: kid is creating a world with thousands or millions of
Speaker 1: artificial beings in it, And so the argument goes, in
Speaker 1: the whole universe there would be many more simulated beings
Speaker 1: than real ones. So if you're a conscious being, meaning
Speaker 1: some kind of entity that thinks they're real. Then the
Speaker 1: odds that you are real are small.
Speaker 2: So what that that means is, if you're the first
Speaker 2: two alternatives, you have to accept the third one. And
Speaker 2: then I argue that conditional that we should think we
Speaker 2: are probably one of the simulated ones rather than one
Speaker 2: of the exceptional non simulated ones. That we are almost
Speaker 2: certainly living inside a computer simulation created by some technolically
Speaker 2: advanced civilization.
Speaker 1: So that is the main argument for the idea that
Speaker 1: we're living in a simulation. It's a logical argument and
Speaker 1: it's a betting argument. There are three possibilities. The first
Speaker 1: two are not true, the third one must be true,
Speaker 1: and that one says that there are advance civilizations out
Speaker 1: there that are simulating millions and millions of virtual lives,
Speaker 1: which means to us that you are one of them.
Speaker 1: Is really high. Like if there are a million real
Speaker 1: people out there, but there are trillions of simulated people
Speaker 1: who think they are real, then the most likely thing
Speaker 1: is that you are one of the simulated ones. Now,
Speaker 1: as you can imagine, there are several big assumptions here.
Speaker 1: The first one is that we could ever have the
Speaker 1: technology to make these planet size relations of billions of brains.
Speaker 1: And the second is that anyone would want to do this.
Speaker 1: Here's how doctor Boston talks about the first assumption.
Speaker 2: So a key premise here, which is that a technolgical
Speaker 2: matricivilization would have enough computing power to run gazillions of
Speaker 2: these simulations. Now, we currently don't have the ability to
Speaker 2: create these simulations because we don't have that technological wherewithal yet,
Speaker 2: but a technolgical mature civilization would have this capability. In fact,
Speaker 2: you could say that even just using the resources of
Speaker 2: a single planet, using only computational architectures that we already know,
Speaker 2: would be possible. For one minute, they could run like
Speaker 2: millions of simulations of all of the brains that have
Speaker 2: existed throughout human history. If you can roughly estimate the
Speaker 2: processing power of the human brain, you can count the
Speaker 2: number of synopsies, the frequency with which they fire, et cetera,
Speaker 2: and you still get the conclusion that, even if they
Speaker 2: are only very slowly interested in this application, the number
Speaker 2: of simulations one of these interested technologically matri civilization could
Speaker 2: run over the course of its lifespan would be in
Speaker 2: the trillions and trillions and trillions.
Speaker 1: Okay, what doctor Boston is saying here is that if
Speaker 1: a civilization is really advanced, and we're talking super futuristic
Speaker 1: humans or aliens that have figured out things like fusion
Speaker 1: energy and can build spaceships, mind asteroids, and conquer other planets,
Speaker 1: then simulating a few billion or a few trillion human
Speaker 1: brains would be easy for them. And you can sort
Speaker 1: of see that even now, we have a huge amount
Speaker 1: of computing power and we can simulate ais that can
Speaker 1: solve most problems humans can.
Speaker 2: And in this argument, you don't need.
Speaker 1: All civilizations to reach this advanced point. If only a
Speaker 1: few do, say one in one hundred or one in
Speaker 1: a thousand, then that would be enough to simulate trillions
Speaker 1: of fake people and outnumber the real ones. And the
Speaker 1: second biggest emgine is why would anyone do this? Do
Speaker 1: you see humanity making these simulations? Is there evidence right
Speaker 1: now that we would make these if.
Speaker 2: We were given the ability right now? If somehow some
Speaker 2: scientists figured out how to just create vastly more powerful computers,
Speaker 2: and if we had the ability to program them appropriately,
Speaker 2: a lot of people would do it for all kinds
Speaker 2: of reasons, like historical researchers would find it interesting to
Speaker 2: run counterfactual runs of history. Game developers might have a
Speaker 2: game setting where there are like real historical people. You
Speaker 2: might want to visit an earlier era. You can't build
Speaker 2: a time machine, so the second best you could do
Speaker 2: would be to create a detailed simulation of this epoch
Speaker 2: in the past, and then you could sort of visited
Speaker 2: as a as a tourist. That might be many other
Speaker 2: reasons as well, or for no reason, just for you know,
Speaker 2: for the heck of it. So right now, yeah, we
Speaker 2: would be running a lot of simulations if it was
Speaker 2: cheap enough to do it easily.
Speaker 1: Doctor Boston's point is that there are lots of reasons
Speaker 1: to create such a massive simulation. It could be like
Speaker 1: a video game, for that advanced revilization, or for research
Speaker 1: or curiosity. And you don't need all futuristic civilizations to
Speaker 1: do it. You just need one or two.
Speaker 2: Now, we don't know that much about technogically mature civilizations,
Speaker 2: so maybe there is this strong convergence, like they all
Speaker 2: realize that it's like morally bad to do this, and
Speaker 2: they all converge on the right ethic. But this second alternative,
Speaker 2: it's hard to rule it out completely. But even if
Speaker 2: most civilizations, say would somehow converge that they would not
Speaker 2: run any of these simulations, like wouldn't one in a thousand,
Speaker 2: one in a million somewhere in the universe do it,
Speaker 2: then that would be not to generate enough of these
Speaker 2: simulations that most people like us would be in the
Speaker 2: simulations now.
Speaker 1: In doctor Boston's original paper, he envisioned future humans running
Speaker 1: a simulation of the past, meaning we think we're in
Speaker 1: the year twenty twenty five right now, but really we're
Speaker 1: in a computer running in the year ten thousand or
Speaker 1: one hundred thousand that is built by one of our descendants.
Speaker 1: But the argument in general also works with aliens.
Speaker 2: Yeah, you could mutter a technodically mature civilization. One type
Speaker 2: of simulation they could do would be simulations of people
Speaker 2: like their ancestors or variations thereof Maybe they would simulate
Speaker 2: people like us. You could also run simulations of potential aliens. Right,
Speaker 2: you don't only have to simulate people you thought inhabited
Speaker 2: your planet before, but you could. So all of those
Speaker 2: are possible, and there would be this population of different
Speaker 2: simulations and simulated creatures of potentially many different kinds like
Speaker 2: the idea of Earth could be simulated and fake. Yeah, yeah,
Speaker 2: that could be the case.
Speaker 1: Yeah. Now what is your personal opinion? Do you think
Speaker 1: that we are living in simulation? Or is your judge
Speaker 1: just to think about these possibilities.
Speaker 2: So I tend to pond on I've often asked, what,
Speaker 2: like the probability is. I tend to like refrain from
Speaker 2: giving a precise num. I do think it's a serious hypothesis.
Speaker 2: I would assign it significant credence, but I haven't given
Speaker 2: a particular specific number. And the simulation argument in and
Speaker 2: of itself doesn't tell us that. It only tells us
Speaker 2: that at least one of these three alternatives is true.
Speaker 2: So if you wanted to conclude that the third alternative
Speaker 2: is true, that is that we are in a simulation,
Speaker 2: you wouldn't have to bring in some additional evidence to
Speaker 2: rule out the other two. All right.
Speaker 1: So that is the red pill, the argument that we
Speaker 1: are living in a simulation, and it's compelling because it's
Speaker 1: hard to rule out all other possibilities, or is it.
Speaker 1: When we come back, we'll take the blue pill and
Speaker 1: talk to a quantum scientist who's going to make the
Speaker 1: case that we are not living in a simulation. And
Speaker 1: then at the end, I'll offer you a third option
Speaker 1: that gets even crazier. So stay with us. You're listening
Speaker 1: to sign stuff. Welcome back the Bluepill. Here's the argument
Speaker 1: for why we are probably not living inside a simulation.
Speaker 1: If you skip ahead, here's the proposed scenario. You and
Speaker 1: I and all eight billion people on the planet right
Speaker 1: now are not real.
Speaker 2: We are all.
Speaker 1: Simulated beings living inside a computer program running on a
Speaker 1: planet sized computer built by a super advanced future human
Speaker 1: or alien civilization. And believe it or not, there is
Speaker 1: a very compelling argument that this is true. But to
Speaker 1: give us the counter argument that we are not living
Speaker 1: in a simulation, I reached out to a couple of
Speaker 1: quantum scientists who wrote a paper titled Probability and Consequences
Speaker 1: of Living Inside a Computer Simulation, in which they argue
Speaker 1: that we are probably not simulated. The authors, Alexander Bibou
Speaker 1: and Guiz brazaar we're working on quantum cryptography when they
Speaker 1: realize that quantum mechanics pretty much throws a big French
Speaker 1: into the whole simulation argument. So here's my conversation with
Speaker 1: the main author of that paper, doctor Alexander Bibo. All right,
Speaker 1: doctor Bibo, thank you so much for joining us.
Speaker 3: It's my pleasure.
Speaker 1: The first thing I want to check is this is
Speaker 1: you right, I'm talking to the real you, not a simulation.
Speaker 2: As far as I know.
Speaker 1: Well, we're talking today about this question of whether we're
Speaker 1: living in a simulation. This is a pretty wild idea,
Speaker 1: because you know, I go through my everyday life and
Speaker 1: feels like I'm in a real place. It feels like
Speaker 1: I'm in actual reality. You wrote a paper arguing against
Speaker 1: this idea. Yeah, now, please spend the next ten minutes
Speaker 1: trying to convince me we are not in a simulation.
Speaker 3: The big thing that in Bostrom's paper and what people
Speaker 3: have this argument discount is the fact that you don't
Speaker 3: need to only simulate the brains of the people living
Speaker 3: in the simulations, but you need to simulate their whole world.
Speaker 3: For instance, this idea that you could build a bunch
Speaker 3: of brains with just a small amount of matter optimize
Speaker 3: according to all the laws of physics, the number of
Speaker 3: brains that could simulate is really really high. That initially like,
Speaker 3: it's very much in favor of their being more simulated beings. Okay,
Speaker 3: but building all this world around these simulated beings will
Speaker 3: require that same level of power, and physics can get
Speaker 3: very complicated, especially quantum physics can be very complicated to simulate.
Speaker 3: So it ends up canceling out, and it ends up
Speaker 3: not being such an argument in favor of there being
Speaker 3: so many more simulated beings. Mathematically speaking, okay, the first
Speaker 3: argument against the idea that we're living in a simulation
Speaker 3: is the fact that it's really hard to make a
Speaker 3: simulation of reality. According to doctor Bibo, you not only.
Speaker 1: Have to simulate a human brain, which is the most
Speaker 1: complex arrangement of matter we know about, but you also
Speaker 1: have to simulate the physical world around that brain, and
Speaker 1: it's especially hard if you make your simulation accurate to
Speaker 1: the level of quantum physics. So whereas before you might
Speaker 1: say that it would be very easy for an advanced
Speaker 1: alien or humans flization to simulate trillions of sentient beings.
Speaker 2: And therefore make it more likely that we are.
Speaker 1: Simulated beings, doctor People argues, it's not that easy.
Speaker 3: It's very hard computationally speaking, to simulate whole worlds, okay,
Speaker 3: especially cold worlds in which there is quantum physics. Okay,
Speaker 3: because quantum computations are inefficient.
Speaker 1: Like if someone were to make a video game and
Speaker 1: we're in that video game, most of their computer, most
Speaker 1: of their PlayStation thirteen would have to be spent running
Speaker 1: quantum physics on.
Speaker 3: It, exactly, exactly, especially if inside the video game they
Speaker 3: don't know they're in a video game and they're starting
Speaker 3: to be curious about their world and they're trying to
Speaker 3: perform like quantum physics experiments, like these scientists are at
Speaker 3: work trying to verify that quantum mechanics is being respected
Speaker 3: as some of our quantum scientists are. It would require
Speaker 3: all the computing power of their advanced PlayStation and the
Speaker 3: game would slow down to a crawl. This is the argument.
Speaker 1: So that's one of the arguments against the idea that
Speaker 1: we are living in a simulation. It's very hard to
Speaker 1: simulate quantum physics. You either need a quantum computer, which
Speaker 1: are really hard to make, or you end up spending
Speaker 1: most of your computing power calculating all of the different
Speaker 1: probabilities that happen all at once in quantum systems. And
Speaker 1: if you want to know more about this, check out
Speaker 1: our episode on quantum computers. Now some people have argued,
Speaker 1: including doctor Bostram himself that a simulated reality doesn't need
Speaker 1: to simulate quantum physics, at least not all the time.
Speaker 1: They could use something called procedural generation. Here's how doctor
Speaker 1: Bostrom describes it.
Speaker 2: In these simulations, you would need a simulation of the
Speaker 2: environment to generate the experiences that these simulated brains have,
Speaker 2: but you wouldn't have to simulate the environment in perfect detail.
Speaker 2: You would only need to simulate the aspects of the
Speaker 2: environment that the simulated brains person eve at a given
Speaker 2: point in time. So it's not the case that every
Speaker 2: single atom in the desk in front of you would
Speaker 2: be simulated continuously, let alone the quarks and stuff. Right.
Speaker 2: I think that that would add massive demands on how
Speaker 2: much computing power it would take, and it would soon
Speaker 2: become infeasible even with like really advanced technology. But all
Speaker 2: that would be required is that the surface appearances of
Speaker 2: your desk are simulated sufficiently that it looks to you
Speaker 2: fully realistic.
Speaker 1: Right.
Speaker 2: And then let's say some physicists in a lab like
Speaker 2: took an electron microscope and looked at a piece of
Speaker 2: your desk, right that they could see potentially individual molecules, right,
Speaker 2: than atoms. So at that point more detail would have
Speaker 2: to be filled in in the simulation, but only in
Speaker 2: the particular piece that they were looking at, so it
Speaker 2: would be sort of procedurally generated.
Speaker 1: This is what's done in a lot of video games today,
Speaker 1: like Minecraft or the Legend of Zelda, where a character
Speaker 1: is free to walk around a huge virtual environment. The
Speaker 1: computer doesn't need to simulate the entire world, just the
Speaker 1: parts that the character sees, and just at the level
Speaker 1: that matters to them. So if a mountain is far away,
Speaker 1: you don't need to simulate every atom or quantum particle
Speaker 1: of that mountain. You can just simulate it as a
Speaker 1: big block or even the table in front of you
Speaker 1: to tap it or put your hand on it. You
Speaker 1: don't actually have to simulate it at the atomic level.
Speaker 1: This would make it easier to simulate a whole reality,
Speaker 1: and therefore make it more likely we are in a simulation,
Speaker 1: But as doctor Bibaut counter argues, it has its limits, and.
Speaker 3: The people who argue for this high probability that we
Speaker 3: are in a simulation, we don't need such higher rate
Speaker 3: of input in order for it to feel real. You know,
Speaker 3: you can play a video game which is fully immersive
Speaker 3: with not much better technology than what we have now.
Speaker 3: You could have like a screen which shows you something
Speaker 3: which to your eyes is indistinguishable for reality. This is true,
Speaker 3: but in order for that world to be coherent and
Speaker 3: for it to like show no inconsistencies in the laws
Speaker 3: of physics everywhere, it has a very very high cost.
Speaker 1: Like right now in our reality. In our world, there
Speaker 1: are physicists running the Large Hadron Collider in Geneva. They
Speaker 1: have atomic microscopes looking down at Adams. If someone is
Speaker 1: simulating our reality, they would also have to simulate like
Speaker 1: every physicist poking around at the atomic level.
Speaker 3: Yeah, exactly, all this stuff in a completely coherent way,
Speaker 3: in a way that no one would find contradictions in
Speaker 3: and all that stuff. Yeah, that would be crazy to do.
Speaker 3: I'm not saying it's impossible. What I'm saying maybe one
Speaker 3: day we will do this, but we will not be
Speaker 3: able to do it on such a scale that we're
Speaker 3: able to drive the number of simulated consciousness higher than
Speaker 3: what there is in reality as far as I can talk.
Speaker 2: Okay, Now, the second argument against the idea we're in
Speaker 2: a simulation is that while a futuristic civilization might be
Speaker 2: interested in simulating reality. They may not be that interested.
Speaker 2: It might not be that much fun for anyone.
Speaker 3: When you have advanced computer the second factor that remains
Speaker 3: is how much of it do you spend on these
Speaker 3: simulations versus on other things?
Speaker 2: What do you mean?
Speaker 3: What I mean is that even if you have these
Speaker 3: advanced computers and someone somewhere like is running all that stuff,
Speaker 3: you need to run other things too, presumably right, and
Speaker 3: you're not just using your computers for simulating brains right now?
Speaker 3: What proportion of all the computing power in the world
Speaker 3: is used to simulate brains? A very small amount. Everything
Speaker 3: else is used to show ads again whatever, for like blockchain,
Speaker 3: or for for a bunch of other purposes. We use
Speaker 3: computing power for everything else. What proportion of all the
Speaker 3: computing power that you do have in your real civilization
Speaker 3: do you use to simulate a world which is indistinguishable
Speaker 3: from reality. So let's say even if your simulation was
Speaker 3: perfectly efficient, then it only used one quantum bit in
Speaker 3: the simulation, which is impossible. But let's say you could
Speaker 3: you spend more computing power on other things, more computing
Speaker 3: power on cryptography than on simulations, for instance. Okay, you
Speaker 3: would still have fewer simulated people than real people.
Speaker 1: So if it was easy and everybody was trying to
Speaker 1: play God in their home computers, then the number of
Speaker 1: simulated realities is huge. Yeah, and we're very likely to
Speaker 1: live in a simulation. But you're saying no, it's a
Speaker 1: really hard and b from what we know over the
Speaker 1: world around us, not everyone is playing PlayStation at the
Speaker 1: same time.
Speaker 3: And sometimes even if we had a very advanced civilization,
Speaker 3: you would not necessarily play games in which the other
Speaker 3: characters are conscious. And see a world that looks like this,
Speaker 3: you might still prefer to play like Super Mario two,
Speaker 3: you know, which, like the Little Turtle guys are clearly
Speaker 3: not conscious.
Speaker 1: The aliens prefer retro games. Maybe all right, that was
Speaker 1: the blue pill. When we come back, we're going to
Speaker 1: ask our two experts how we might settle this debate.
Speaker 1: Could we ever tell if we are living in a simulation?
Speaker 1: And then at the end, I'm going to offer you
Speaker 1: a purple pill, which I have to warn you might
Speaker 1: blow your mind, whether it's simulated or not.
Speaker 2: So stay with us. We'll be right back.
Speaker 1: And we're back, all right, Whether you took the red
Speaker 1: pill or the blue pill, or maybe both. You might
Speaker 1: be wondering if we could ever tell that we are
Speaker 1: living in a simulation, How can we know if we're
Speaker 1: living in the matrix. I asked both our experts this question,
Speaker 1: and this is what they said, Could we ever tell
Speaker 1: if we were one of those simulated consciousness?
Speaker 2: So that would depend on the simulation. So if the
Speaker 2: simulators wanted to reveal this curtly to do that, you
Speaker 2: could imagine like a window popping up in front of
Speaker 2: your visual field saying here, you're in a simulation. Click
Speaker 2: here for more information. Right, that would be a pretty
Speaker 2: conclusive proof. Short of that, I think there are indicators
Speaker 2: that the closer we get to technological maturity, the less
Speaker 2: likely the first alternative becomes. Right, Like, if we look
Speaker 2: like we're almost there, then it doesn't seem the case
Speaker 2: that almost all civilizations that our current level will go
Speaker 2: extinct before reaching technogical maturity. I see, And if we
Speaker 2: at that point remain interested in creating ancestors simulations ourselves,
Speaker 2: just like we right now run a lot of computer
Speaker 2: grames and three D virtual realities and scientific simulations for
Speaker 2: all kinds of purposes. Right, if that remains the case
Speaker 2: as we get really close to being able to do
Speaker 2: this ourselves. That would really start to roll out the
Speaker 2: first two alternatives, and it would then force us to
Speaker 2: infer that we are almost certainly simulated ourselves.
Speaker 1: Let's say we were looking for evidence that we are
Speaker 1: not or that we are living in simulations. What are
Speaker 1: some of the things we could be looking out for.
Speaker 3: One of the things I do mention in the paper
Speaker 3: is that if you're looking for violations of these laws
Speaker 3: of physics, they could be very subtle. They could just
Speaker 3: be errors in quantum correlations. So some of the experiments
Speaker 3: we perform to understand how quantum mechanics work, they could
Speaker 3: have noise that we're not able to explain. And same
Speaker 3: thing when we're doing quantum cryptography. In quantum cryptography, your
Speaker 3: piece to p people at the end, they're exchanging information
Speaker 3: on something which is a quantum channel. And if there
Speaker 3: is noise in this experiment in this communication, usually you say, oh,
Speaker 3: the noise is there because someone is puying on the information.
Speaker 3: Someone is trying to intercept part of these photons to
Speaker 3: get information out of them. If this was happening, if
Speaker 3: you do see noise and no one can explain away,
Speaker 3: this could be an indication, for instance, that we are
Speaker 3: in a simulation and that these correlations in physics are
Speaker 3: violated because there is either a bug in the simulation
Speaker 3: or they're using part of this information to look into
Speaker 3: what's happening in our world.
Speaker 1: I see, like, if we test the lots of physics
Speaker 1: and we find errors or weird things happening, then that
Speaker 1: might be a clue.
Speaker 2: That we're in a simulation.
Speaker 3: Yeah, I believe so.
Speaker 2: But do they have to be at the quantum level?
Speaker 3: This is probably where they would happen, because it's much
Speaker 3: harder to get quantum computations correctly without noise than it
Speaker 3: is that anything else to happen. You cannot observe it
Speaker 3: without disturbing it. In that sense, if the laws of
Speaker 3: physics are truly quantum, and we have good reason to
Speaker 3: believe that they are, then even from outside the simulation,
Speaker 3: trying to observe them in that way could disturb them
Speaker 3: in a way which we could measure.
Speaker 1: Okay, So to tell if we are in a simulation,
Speaker 1: you can do one of two things. You can look
Speaker 1: at the world around us and see how it affects
Speaker 1: the philosophical argument. For example, if it looks like our
Speaker 1: civilization is about to crash and burn, then maybe that's
Speaker 1: common and there aren't any advanced civilizations out there. Or
Speaker 1: if we find that playing video games or running realistic
Speaker 1: simulations is not a high priority for us, then maybe
Speaker 1: it's not for any civilizations out there either. The other
Speaker 1: thing you can do to tell if we're in a
Speaker 1: simulation is you can look for glitches in the matrix.
Speaker 1: If you run quantum experiments and find that things don't
Speaker 1: quite add up, then that may be a sign that
Speaker 1: we are simulated. Or as doctor Bobo said, you could
Speaker 1: try to break the simulation. You could overtax it, maybe
Speaker 1: by doing a lot of quantum experiments or running your
Speaker 1: own simulations within the simulation, although that could be dangerous.
Speaker 1: So poking at the loss of physics is one way
Speaker 1: to test whether we're in a box or not.
Speaker 3: There are other ways, which could be trying to make
Speaker 3: our own simulation, so trying to keep acquiring technology and
Speaker 3: increasing our computational power and trying to make our own
Speaker 3: simulated worlds. If we use too much, I mean, we
Speaker 3: could be slowing down their simulation and they could be
Speaker 3: tempted to turn it off or to do something about it.
Speaker 3: Which maybe is not so smart if we think we
Speaker 3: are in a simulation.
Speaker 1: So yeah, if we are in a simulation, maybe we
Speaker 1: don't want to do anything that might make whoever is
Speaker 1: running the simulation stop because it may not matter. Here's
Speaker 1: the last question I asked, doctor Buster. Do you think
Speaker 1: there's a difference between a simulated reality and a real reality?
Speaker 2: Well, that depends that on the simulation. I think that
Speaker 2: could be very close. If the simulators wanted to make
Speaker 2: it as accurate as possible, I think that could make
Speaker 2: it pretty accurate. And if ever there were like some
Speaker 2: glitch or some anomaly, then they could sort of edit
Speaker 2: the memories of whoever detected that or sort of patch
Speaker 2: things up. You imagine these simulators as being super intolent.
Speaker 2: One of the things that could do with our advanced
Speaker 2: technology would be to make themselves smarter.
Speaker 1: Well, I really appreciate your time here, and it's been
Speaker 1: a real experience to talk with you, hopefully not a
Speaker 1: simulated one.
Speaker 2: The experience is real now, the implementation of it is
Speaker 2: more hidden in a shroud of uncertainty.
Speaker 1: I guess all right. The last thing I'm going to
Speaker 1: do is offer you a purple pill. This is an
Speaker 1: idea that might be even crazier than the idea that
Speaker 1: we're all living in a simulation put on by some
Speaker 1: alien civilization out there in space, an idea that came
Speaker 1: up when I was talking to doctor Bubo about how
Speaker 1: he got interested in the idea of a simulated universe.
Speaker 3: So basically I was working on seeing physics as a
Speaker 3: potentially computation no thing, saying like, okay, like could physics
Speaker 3: at its most base level be a computation?
Speaker 2: What do you mean physics being a computation?
Speaker 3: So saying that if you're trying to understand the laws
Speaker 3: of physics, a good way to understand it is from
Speaker 3: the perspective of what is the informational content of physics
Speaker 3: and what we perceive as time evolution of systems. How
Speaker 3: could this represent a type of computation? You would say
Speaker 3: that at some point this would mean that on the
Speaker 3: most microscopic level, space and time are discrete.
Speaker 1: And I think you're saying that maybe the laws of
Speaker 1: physics are just a program.
Speaker 3: Yeah, any physical system, because it's state changes with time,
Speaker 3: and it's taking like an input state, doing something and
Speaker 3: getting an output state at the end, it's performing a computation.
Speaker 3: So in some sense, the laws of physics as a
Speaker 3: whole could also do that.
Speaker 1: Maybe, like the laws of physics were a program, but
Speaker 1: they weren't running in a computer. They were just running
Speaker 1: on the.
Speaker 3: Universe exactly exactly. The universe is kind of like a
Speaker 3: natural computer that just happens to be there.
Speaker 1: In other words, the real actual universe itself could be
Speaker 1: a simulation, which means the answer to the question are
Speaker 1: we living in a simulation could be yes, but it's
Speaker 1: a simulation that is being run by no one. As
Speaker 1: Neo famously said in The Matrix WHOA. Thanks for joining us,
Speaker 1: see you next Wednesday. You've been listening to Science Stuff
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