Episode 57: Quantum Immortality / Quantum Torment

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Unofficial, reviewed transcript. It may still contain mistakes; check the podcast when wording matters.

Speakers are labeled by first name where identified. Unidentified-speaker labels may refer to different people. Bracketed question marks indicate uncertain wording.

Transcript

[00:00:10]  Peter: Hello, Bruce, Cameo.

[00:00:12]  Bruce: Nice to talk to you.

[00:00:13]  Unidentified speaker: Hello.

[00:00:14]  Peter: I've got to say that I am really excited for this conversation, maybe a little more than usual even. Today, we're going to be talking about quantum immortality. When I first read The Beginning of Infinity, this is one of the, I would say, the things that really struck me as kind of a revelation. And, you know, this kind of relates to our religion conversation last week, where we spoke about parallels between Deutschianism and religion. This is kind of another one. At least what I got from The Beginning of Infinity, and I think it would be hard not to make this connection. I mean, it's a really simple argument in a way. A, the multiverse is real. Okay, I think we agree with that. B, death is soluble. Goes along with the principle of optimism pretty well. My conclusion, at least, is that somewhere in the multiverse, we live forever, hopefully in harmony with our loved ones.

[00:01:11]  Peter: Hopefully, I can bring back my dog, whatever. So after I read the beginning of Infinity, I told my wife about this, I told my kids about this, told my friends, my co-workers. Not very many people care.

[00:01:24]  Unidentified speaker: It's been my experience.

[00:01:27]  Peter: So they think it's weird. Sounds really weird. And I don't know. I mean, usually it will lead into a conversation about many worlds. I asked my wife the other day, I said, well, are you at all convinced? We've talked about this the last few years. I've been into this. And are you at all convinced that many worlds is a possibility? And she says, well, a little, but I don't really care. And I mean, I don't blame her. She's into her own thing, music and art. And it's just not something that she spends too much time thinking about. And most people are like that, I mean, from what I've experienced. It's hard for me to understand. This is immortality and it's real and it's physics. It's not theology. Just on the level of basic curiosity, I want to know. I mean, in the same way, I want to know where humans come from. Do we evolve from apes? I want to know about Einstein's theory of relativity.

[00:02:29]  Peter: And this is what I would consider the most positive aspect of quantum immortality. We're also going to get into some rather dark aspects of quantum immortality. Quantum torment.

[00:02:45]  Bruce: Oh, yeah.

[00:02:47]  Peter: We can discuss.

[00:02:49]  Bruce: But let's stick with the positives.

[00:02:51]  Peter: What are your thoughts, Bruce?

[00:02:53]  Bruce: Okay, so let me just say that I've hung out for a while with people who are fans of David Deutsch and try to talk with them and things like that. And a lot of the podcast ideas come from me arguing with them and I'm trying to make my case. I've asked a number of them, have you given any thought to the idea of quantum immortality? That there might actually be something like an afterlife, a Tipler, Omega Point-like thing. And every single one of them has told me, no, I've never given it any thought at all. So this is a group that believes in many worlds and loves David Deutsch's books. And they've really kind of not given this much thought. And it just isn't something that seems to ever cross their mind, that, you know, is this actually... Even Deutsch himself significantly downplays this in his first book, The Fabric of Reality. He almost seems to me like he's arguing against it.

[00:03:49]  Bruce: I'm probably reading too much in there. But at a minimum, he's very neutral on the subject, maybe even against it. And he argues that that aspect of Tipler's theory is based on the assumption that we know what they're going to choose to do with their knowledge. As I argued in the previous episode, that's not right, right? Because if we're talking many worlds, then it just has to be that it's possible that someone decides that we can solve death all the way, bring back people who were previously dead. And if you can do that, then somewhere across the multiverse, someone should do that. And so I never understood that aspect of why David Deutsch was downplaying that, or why it just doesn't seem that interesting to people. To me, that was the single most interesting part of David Deutsch's book for a variety of reasons.

[00:04:40]  Unidentified speaker: We're on the same page too.

[00:04:41]  Peter: And I've noticed that even on the Facebook group, it's been a little hard to get discussions on quantum immortality going. It's almost like an aspect compared to, I don't know, say free will or AGI or some of the other issues that seem to generate a lot of thoughts for some reason.

[00:05:06]  Bruce: Can I give you my opinion? Just a straight opinion. And I apologize to my audience since a lot of them might not like this opinion. I think it's way too close to religion. I think it's so close to religion. I think it is religion. And I think that the moment you really start taking it seriously, you're taking religion seriously. And I think that's not the way most people who are interested in these theories want to present or think of themselves. So I think it's a line that only a religious person like myself can be comfortable crossing really easily. And so to me, it becomes this really interesting scientific question. And I don't have any concerns about, oh, it feels really religious. But I think that most people who would be interested in Deutsch's Four Strands, things like that, into philosophy, into science, they probably want to present themselves as hard headed atheists and this is just across the line for that.

[00:06:03]  Bruce: So the fact that it's actually a real scientific question, I mean, it is a scientific question. Maybe it's not right, right? Maybe we're getting something wrong, but it's like a totally legitimate scientific question.

[00:06:13]  Peter: I mean, once you accept the validity of many worlds, which is, of course, its own conversation that you've had before, you know, then it just becomes a matter of, well, is death a soluble problem? Which, according to the principle of optimism, all evils come from lack of knowledge and all problems that are interesting are solvable. And certainly that would include death. I would actually, on a big picture, I would consider, think of that as maybe a pretty easy one, really.

[00:06:47]  Bruce: You know, we may need to explain this to Cameo a bit, because she wasn't in the last episode where we talked about the Omega Point. So we just listened to the Omega Point episode, and then this one came out afterwards. And so they know exactly what we're talking about. But Cameo doesn't have the advantage of that. OK, so let me let me just briefly explain. So there's this theory called the Omega Point theory. Came from a guy named Frank Tipler. Frank Tipler is, in fact, the original four strander, not David Deutsch. But Tipler is also, depending on what time period you're talking about, a religious person. And he equated the Omega Point theory with theology. And so that really turned off other potential people that might otherwise find interesting, David Deutsch being an interesting exception. He wrote a book about the Omega Point in 1994.

[00:07:37]  Bruce: David Deutsch's book Fabric of Reality comes out in 1995. No accident. He clearly had read Tipler's book and it inspired, kind of brought together, allowed him to take the other things that Deutsch had been thinking about that are the strands throughout the book. And he twines them all together at the end. And he shows, really, the four strands give us a totally new, non pessimistic scientific cosmology. So one of the things I talked about in the previous episode, Cameo, is that the normal cosmology of physics that almost every physicist you're going to come across, unless they're religious, is going to believe in is heat death. And heat death is about as pessimistic a cosmology as you could possibly imagine. It is hellishly bad, although nobody ever talks about that. I think if scientists that are atheist physicists were to really stop and think through their cosmology all the way, it would just be bad, so they don't.

[00:08:36]  Bruce: And one of the things that attracted me to Deutsch's Four Strands is his books. It was the first time I ever had the thought, oh, science isn't naturally pessimistic. That's just the way we currently look at it. There might actually be an optimistic way to look at science. And that was what I loved about the fabric of reality is that at the final chapter, he lays out, this all may mean that the correct cosmology is something more like the omega point rather than like heat death, the optimistic cosmology versus the pessimistic cosmology. Now, one of the things that comes out of that, though, is if you do have an omega point like cosmology, which basically boils down to, never mind the collapsing universe for the moment. We talked about why Tipler's theory is somewhat questionable. But just the basic idea that progress continues forever, that there's an infinite amount of progress possible, that we can keep making—Moore’s law goes on forever.

[00:09:31]  Bruce: We can continually keep finding ways to increase the speed of our computations. In such a world, it's not just that death— I mean, like most people would agree, death is just a problem to be solved, even if they haven't given it much thought. The idea that we could solve individual death and make ourselves live for very long periods of time, as long as the universe exists, which in an Omega Point cosmology, that would be forever. In heat death, it's not forever. Yes, you can solve that death in that sense, but can you solve it in a broader sense? Could you, for example, bring back everyone who died before us and bring them back to life again? Well, if you have enough computation and you've got enough knowledge, then it's just a solvable problem, right? It's just a problem that's just a matter of waiting until your computers, you understand the universe well enough, you understand physics well enough, and then you could create a simulation of the entire universe or really the entire multiverse, and you can run it and you could find every single person that ever lived in our past and that has died, and you could bring them back to life, which might be a really interesting thing to want to do, to bring these other minds that have existed

[00:10:42]  Bruce: and might even have survival value for people in the future. If you had the option to bring back Einstein, wouldn't that be a good thing, right? You've got this really unique thinker that you probably want to have part of your society, right? And that would really be true for absolutely everybody, though. Even people that died unknown, you've never heard of them, cavemen or whatever. How might they impact the search for knowledge if you brought a mind like that back from the dead and let them join a modern society, modern in this case, meaning something way into the future, way more advanced than what we have. It seems very reasonable that if it is a problem that can be solved, it will be solved, in which case it would be very natural under the laws of physics for some future, far future society to start bringing back people from the dead.

[00:11:33]  Bruce: And that's really what Peter's talking about in terms of quantum immortality. This is the optimistic side of quantum immortality. There's a downside that we have to talk about too.

[00:11:42]  Unidentified speaker: Okay.

[00:11:43]  Unidentified speaker: All right.

[00:11:43]  Cameo: Thank you for the recap.

[00:11:45]  Unidentified speaker: Okay.

[00:11:46]  Peter: Can I ask you a question about the multiverse theory relevant to this?

[00:11:54]  Bruce: Well, okay.

[00:11:54]  Peter: Wait, just to summarize. So, yes, the multiverse is real. Death is soluble. Humans of today, presumably, were at the right time in history, I would imagine, where at least somewhere in the multiverse, maybe it's just one branch, but I would imagine it'd be a lot. They're going to figure out how to download our brains onto a computer or whatever. They discover the mystery of consciousness, and we're good on the Dyson sphere, or it sounds like whatever, at least until the heat death, omega point stuff is kind of its own thing, but at least for a while we're good. But then, what about people 100 or 1,000 years ago? How I interpreted the multiverse theory when I first read about it was that everything that could possibly happen according to the laws of physics, I know that's a tautology, but I think you get what I mean, plays out in some branch of the multiverse.

[00:13:00]  Bruce: That's correct, yeah.

[00:13:01]  Peter: Which would most likely include someone in the Middle Ages figuring out relativity and quantum theory and, you know, inventing a computer and living forever.

[00:13:14]  Bruce: So there's just versions of Earth where the Enlightenment started hundreds or thousands of years earlier. Absolutely. So we should have, really, humans have been around for, I think, 2 million years, right? So Deutsch, when he talks about all problems are soluble, I wanted to do an episode where we got a panel together. Maybe we'll do that in the near future. I don't fully understand what he means by it. And Lee Cronin, he's pointed out that these things take time. Like we're in a search process. You have to have certain kinds of knowledge before other kinds of knowledge can become possible. So there is a certain amount of time or computation that must take place to be able to get to a certain advanced state of knowledge, right? You can't just say, instantaneously, it takes place. That just isn't going to happen.

[00:14:03]  Peter: Not even in a low amplitude universe, in the multiverse, it wouldn't happen that some guy like Einstein to the 10th power wouldn't have just thought of all the necessary knowledge.

[00:14:18]  Bruce: All at once.

[00:14:19]  Unidentified speaker: All at once.

[00:14:20]  Peter: So there are things that don't happen in the multiverse. I guess that's what I really wanted to get at.

[00:14:27]  Bruce: Right. So Deutsch has argued, he originally took the stance, everything that can happen happens in the multiverse, but that's really only true to whatever the actual limitations are. So he would have said limitations of laws of physics, but really there are other kinds of limitations. You can call them by the laws of physics or not. But certain types of knowledge have to happen first, take certain amount of computation. Then there's things that you don't want to have happen. So you put things in place and it would make sense that those would start to disappear out of the multiverse, those possibilities. There's a certain sense in which, yes, you can say everything that can happen happens in the multiverse as long as it's physically possible. But exactly what we mean by that is far less clear. And so in a lot of ways, that's what we're still trying to figure out is what does it mean physically possible.

[00:15:17]  Bruce: It's physically possible, has to take into consideration Lee Cronin's theories, it has to take into consideration the laws of physics, it has to take into consideration the very fact that we're trying to do error correction. So let me give you an example of this. A lot of times the multiverse has been presented as every choice you could make you made. Well, that's not really necessarily true. That's like a very simplistic understanding of the multiverse and not even necessarily a realistic one. So for example, let's take Cameo as an example. Cameo is a decent person, right? So she could in theory decide to do something really awful, just kill somebody on the way home for work just for fun or something like that. So does that mean that there's some version of Cameo in the multiverse where she did this? Well, no, right? Because that's not something that's part of her program, most likely.

[00:16:13]  Bruce: It's running in her brain. And so that would actually in some sense defy the laws of physics for her to choose to do that. You might get around that by claiming that there's this weird quantum event in her brain and it causes her to not be herself. Okay, but at this point, she's not Cameo. So we're kind of outside the bounds of the original question, right? So in a certain sense, yeah, we can imagine a version of Cameo doing something really awful. But it doesn't necessarily happen in the multiverse because there's a certain sense in which that would seem to violate the laws of physics that it could happen.

[00:16:52]  Peter: So take home point, there are what Deutsch, I think, calls Harry Potter universes. I hope I didn't make that up. Where really fantastical things happen, but not every fantastical thing happens.

[00:17:06]  Bruce: So let me explain the Harry Potter universe. It's a really weird concept. So imagine that I take a wand, and I say Wingardium Leviosa to Cameo, and I try to levitate her using that spell. Well, there is no such spell Wingardium Leviosa, right? It's denied by the laws of physics. But there is some universe out there in the multiverse where the moment I say that, some weird set of quantum events happen, and the wind comes and picks up Cameo and then drops her again. It's actually just a total coincidence. But it really seems like that spell worked. Now, if you can buy that that universe exists, then you have to buy that there's a universe where I try it again and the same coincidence happens. And then I try it again, and then the same coincidence happens. Okay, in that universe, which, by the way, Deutsch doesn't even call it universe. I don't know why, but he doesn't refuse to refer to them as universes.

[00:18:10]  Bruce: There would be a some group of people where they really think I'm a magician, because it just so happens that every single spell I cast happens to take place. That's the Harry Potter universe. It doesn't actually technically violate the laws of physics, but it's a universe in which, just due to random changes to quantum physics, that just take place naturally anyhow, there is effectively a new law of physics that Wingardium Leviosa works at least when I do it, right? [I can?] shoot lightning bolts and things like that. It's actually just total randomness. Now, obviously, that universe would be increasingly improbable. Having me do it once would be highly improbable. Having me do it twice would be exponentially improbable. And then every single time having to happen would just be exponentially, exponentially less probable. And yet, it shouldn't be that there's some place out in the multiverse where just that weird set of coincidences actually did take place.

[00:19:14]  Bruce: And that society would see the world very differently, and their world would be inexplicable, right? They would have this weird set of coincidences that seemed like universal laws, and it would be completely impossible to explain them, because they're actually just coincidences. So I think that's why Deutsch refused to call it a universe, is because those universes are inexplicable, basically. The idea of explanatory universality does not exist in those universes.

[00:19:44]  Peter: So we don't have to worry too much about universes where we decide to become serial killers or something like that, or do something completely preposterous.

[00:19:56]  Bruce: So I don't think so. But of course, we're still making assumptions, right? We don't fully understand how the human mind works. We don't know how much it uses random effects. So it's hard to answer that question. But there's no particularly good reason to believe we should have to worry about it.

[00:20:14]  Peter: I mean, there's a lot of universes, I guess, I heard someone, I hope this is right. Someone said that if you were to write out the number of universes, just write it out, just that act of writing would create so much mass that it would start another black hole and destroy the universe.

[00:20:37]  Bruce: So it's a big number.

[00:20:42]  Peter: Should we move on to quantum torment?

[00:20:45]  Bruce: So, quantum torment. So let's talk about quantum suicide maybe first, because that really helps you understand the concept of quantum immortality, the less optimistic version of it, and then ultimately quantum torment, the ultimately pessimistic version of it.

[00:21:03]  Peter: Was it Tegmark who came up with the idea of quantum suicide?

[00:21:06]  Bruce: You know, I'm a little unclear if he actually came up with it, or if he is just the first one to popularize it. I think he may have came up with it. And he doesn't believe in it, by the way, at least according to the book of his that I listened to. So it was an interesting thought experiment. Tegmark likes cool dumb stuff like this. And it makes sense. You want smart people really thinking out there beyond the edge of what makes sense, trying to push the boundaries, because that's how you push the boundaries and more things make sense.

[00:21:40]  Peter: Right. Mathematical universe hypothesis. So I do recall him saying very clearly that he does put many worlds in a different category than all the other multiverses.

[00:21:54]  Bruce: So and he should. So like, Deutsch doesn't really give credence to any of the multiverse theories except the quantum one. So, Cameo, you may not know this, but there's actually like if you look up Max Tegmark's website, there's like four different classes of multiverse. Okay. And the quantum multiverse that we talk about in this podcast is only one of them. So like another one might be that the universe is just infinite. So there's an infinite amount of matter. So it's guaranteed that if you could somehow travel faster than the speed of light, which you can't. If you were to go fly out into the universe, you would eventually find another planet where matter happens to have come together, where there's a Cameo and there's a Bruce and there's a Peter. And they're having exactly the same conversation that we're having right now. But and then it differentiates a little bit, just like a quantum multiverse would.

[00:22:46]  Bruce: So that would be like a totally different kind of multiverse that has nothing to do with quantum physics, but has a lot of the same elements to it that the quantum multiverse has.

[00:22:56]  Peter: I think that Brian Greene then expands it to about 10 different kinds. He brings in string theory and all this.

[00:23:02]  Bruce: So, yeah, so string theory makes some similar sorts of predictions. Here's the thing, though. These other types of multiverses are based on theories and cosmologies and such that aren't best in class theories. So if you do it based on string theory, string theory, as we've talked about, it's not even an empirical theory. So it just does not get to be counted as in the same category as quantum physics. Okay, this is, by the way, the argument I keep making to Sadia over her theories is certain theories that have been highly corroborated, they are different. That is what makes them different. They're so good that they make tons of predictions. They have really heavy empirical content, and we've tested the heck out of them, and we can't find counter examples to them. Right? So quantum physics is in its own little category. String theory is not the same.

[00:23:56]  Bruce: Inflation is not the same. None of these other theories that might lead to multiverses, none of them are in the same category as quantum mechanics. And then you have to think, you have to invoke a multiverse to be able to explain quantum mechanics, whereas you don't have to invoke a multiverse to say, try to explain, like, you could have inflation, but with a finite universe, for example. So there's no particular reason why it has to mean that there's a multiverse, right? So because of that, there's really only one serious multiverse in science today. That's quantum mechanics. The others are just kind of out there, interesting speculations. Does that make sense?

[00:24:39]  Peter: Oh, yeah.

[00:24:40]  Bruce: So, okay. So Tegmark, one of the things I really like about Tegmark is that he'll just explore anything. One of the things I don't like about Tegmark is that he doesn't do a great job of differentiating between wild speculations and actual good theories.

[00:24:55]  Peter: Yeah, it does occur to me that it must really confuse people who are interested in the multiverse. When you suddenly have you Google it and you'll get 10 different kinds. It's really, really in some ways, it's unfortunate that, you know, I mean, people, when I tell people about the many worlds interpretation, they think it's just something out of a Marvel movie or something.

[00:25:17]  Bruce: Right, because it is something out of a Marvel movie.

[00:25:21]  Peter: Fair enough.

[00:25:23]  Bruce: So Tegmark, like I said, I don't know if he came up with it, but either he came up with it or he popularized this idea of the quantum suicide. So using quantum mechanics, you can imagine an experiment that's something like this, where you have a gun and the gun is connected to a quantum device. The quantum device has the decay of a particle. This is the Schrödinger's cat experiment. But basically it's that experiment, but you put yourself in the box. OK, so the Schrödinger's cat, I did not say that right. I never say that right. You have a quantum event that breaks a vial of poison and it kills the cat in the box, or it doesn't kill the cat in the box. Well, because the quantum event is a superposition, and the way you explain that is through a multiverse, then we would say that the cat is in a superposition of being both alive and dead until you open the box, make an observation, and then the wave function collapses, and then the cat either becomes dead or it becomes alive.

[00:26:26]  Bruce: Well, now if you take the multiverse seriously, then what actually happens is you open the box, and then either you then split, and either you see, this is the version of you that sees the dead cat, or this is the version of you that sees the live cat, okay? And then now you're in superposition as well, okay? And based on this then, what if you put yourself in the box? What if you had a gun that goes off, it shoots you, and it's going to do that based on the superposition of a quantum particle? Then what you should, so goes the argument, what you should perceive is that if you're not in the box and you're just watching it, the gun will sometimes go off and sometimes won't. So imagine that it decays every second, and so it's basically a random event takes place every second, 50% of the time the gun goes off, 50% of the time the gun doesn't go off.

[00:27:19]  Bruce: So it goes, so a click would be not going off, a bang is going off. So it would go click, click, bang, click, bang, bang, bang, click, click, click, click, bang. And that's what you would see if you're outside the box. If you get into the box and the gun's aimed at your head, now we're assuming the gun's high enough power that you die instantly, then what you perceive is click, and the bang never happens. Because you're dead in the universe where the bang happens, so you can't perceive it. So the you that you think of yourself as can only ever perceive the click, the gun never going off. Okay, so even though that's highly improbable, that would be what you would perceive. And then Tegmark also throws in there, at some point, the odds of you having that many clicks is so low that it's much higher probability that the power in the building goes out.

[00:28:19]  Bruce: And so suddenly you'd find the power goes out and your experiment can't continue or something along those lines. Okay. Now, if you were to try this experiment, and let's say it actually worked, Tegmark later argues that maybe this is a misunderstanding of quantum mechanics. But let's say that it worked. You would then know that you lived in a multiverse.

[00:28:38]  Peter: You might as well tie it into winning the lotto or something too. Wake up a millionaire or whatever.

[00:28:46]  Bruce: Because you've killed off all the versions of yourself in all the other universes, the you that's left now has pretty good reason to believe that the multiverse is real. So it's an experiment to try to prove to yourself the existence of the multiverse. Now, nobody else is going to take you seriously because you died in all the other universes, right? And so they just saw you die, so they've got no reason to believe they live in a multiverse. And so it's an experiment that is purely subjective. Even if it's a real thing, you can only ever prove to yourself that the multiverse is real.

[00:29:25]  Peter: But can I just throw out one other thing about that is that it seems to me that what makes it nothing more than an interesting thought experiment is that there's always going to be universes where the bullet lodges in your brain and you don't die, or the machine malfunctions. It seems to me there's always going to be a lot more of those universes than the one where you wake up as a lotto winner or something. So I just want to put that out there in case that someone comes across this podcast and has actually thinking about doing it or something like that, which it probably would not be practical as a test for many worlds in real life.

[00:30:11]  Bruce: So let me actually describe what you just said a little bit more clear because it's actually a really fair point. Let's say that you did a modification of the quantum suicide experiment where you're going to reveal your lotto ticket, and if you are a loser, the gun goes off and you die. And if you're not a loser, then you've won the lotto. So you could make the claim, well, I'm going to put myself inside the box, I'm going to have the gun go off if I lost the lotto, then I'm absolutely guaranteed to perceive myself as winning the lotto, and I'm going to get to live as a millionaire for the rest of my life, and I don't care about the other universes where I no longer exist. So you might think this is a legitimate thing for you to try to do, but it's not, because the odds of winning the lotto are so low that there's a better chance that the gun doesn't go off.

[00:31:01]  Bruce: Or so this experiment, or that it just kills you slowly and painfully, or something along those lines. So because of that, this is more a thought experiment than it is probably something that anyone should want to go out and actually try.

[00:31:21]  Bruce: And I think this is one of the reasons why Tegmark doesn't really believe in the Quantum Suicide Experiment. By the way, Quantum Suicide Experiment showed up in Alan Wake, the video game. They have, when you go around playing the excellent game, when you go around playing the game, you come across televisions. On every single television you come across, there's an episode of a show going on that's a Twilight Zone parody. And so they have very quickly, in the middle of this game, you have a little mini Twilight Zone episode that you can watch. And one of them was about Quantum Suicide. I just thought that was interesting that it had become a popular enough idea that it had made it into a piece of popular media. And you've probably maybe even seen it. This is something that has shown up in other places as well. I've seen since then. So it made its way into the media.

[00:32:09]  Bruce: So hey, now we're golden. So if the Quantum Suicide Experiment were correct, which we're saying is questionable, then this raises a question. Isn't everything, isn't all of life sort of like a Quantum Suicide event? Yeah. So let's say that I'm walking across the street and I get like Stephen King, I get hit by a car, and there's a good chance I'm going to die. So in the universes where I die, I never become conscious again. And so I stay dead. But there's some small percentage chance that I'm going to recover. And so that's the universe I wake up in. So if I get hit by a car, I'm not going to merely perceive myself dying, because you can't perceive yourself dying. I'm going to perceive myself as having survived the encounter. So basically under this way of thinking, you can never actually perceive yourself dying. This is the kind of darker side of quantum immortality, where you will always perceive yourself as living long enough that all your loved ones die, and then you just keep getting older, everyone around you dies, and you never actually perceive yourself as actually dying.

[00:33:17]  Bruce: So you could take this to its kind of extreme logical conclusions. You can imagine that you just somehow always stay just barely conscious, barely yourself, and you get older and you get more wounded and more bad things happen to you. And finally, you're just in constant torment for eternity. That would be the idea of quantum torment. And it's really a terrifying thought. And even just the fact that it kind of makes sense under the theory, I had never given something like quantum torment any serious thought prior to the realization that many worlds might actually be the truth, right? And that we actually have a theory that says that it is. And then I started wondering, is quantum torment actually something I need to worry about?

[00:34:00]  Peter: One interesting thing I just learned this week is that apparently Hugh Everett was a believer, at least according to his autobiographer, was a believer in quantum torment. So he, the originator of the many worlds interpretation, did accept this as a natural conclusion of his theory. The daughter, who I think committed suicide herself, in her note said that she was going to join him in the multiverse or something.

[00:34:27]  Bruce: But that's sad.

[00:34:29]  Unidentified speaker: Yeah.

[00:34:29]  Unidentified speaker: Yeah.

[00:34:31]  Peter: I think a very troubled person, but his son is, this is a complete side tangent, but his son is an amazing musician too. You've seen that documentary, right, about him discovering his father's ideas?

[00:34:47]  Bruce: No, I have not. I've seen it as a documentary. I haven't seen it yet.

[00:34:52]  Peter: Yeah. He's a singer for a band called The Eels, which is, in my opinion, a very good band. And he's an amazing songwriter.

[00:34:59]  Unidentified speaker: The Eels are great.

[00:35:02]  Unidentified speaker: That's crazy.

[00:35:03]  Unidentified speaker: Yeah.

[00:35:04]  Peter: Oh, you like them?

[00:35:04]  Unidentified speaker: Good, good.

[00:35:05]  Peter: And yeah. And I think, you know, his father was, well, a troubled person, we'll say that, a genius, but troubled person. He grew up not really knowing anything about his father's ideas. And then this documentary is about him meeting David Deutsch is in it, and I think Max Tegmark and other famous physicists explaining his father's ideas to him. And he said that it was one of the most meaningful experiences of his life, was making this documentary.

[00:35:39]  Bruce: Everett was considered a failure, right? I mean, he went into physics, he did this paper, he got lucky that John Wheeler backed it. And then like, he wasn't really considered a good physicist after that. It seemed like crap science at the time.

[00:35:54]  Unidentified speaker: Yeah.

[00:35:55]  Bruce: Kind of just fell out of being a physicist and did other things with his life after that, if I understand correctly. So yeah, it's... So now, is quantum torment something that we should worry about? Honestly, I don't know for sure. So there is a little bit of worry in the back of my mind. But let me talk about some of the things that like Tegmark and others, we also have this paper, Should We Fear Quantum Torment, that I sent to you guys by a name that I cannot pronounce. István Aranyosi. And they've talked through, is this actually what would follow from the theory, even if we're just taking it seriously. So Tegmark points out something that actually makes a lot of sense to me, that really there's a kind of a halo that exists across the multiverse. So like, let's say that I get old and I start to turn senile. I don't disappear all at once, but I do disappear, right?

[00:36:51]  Bruce: My body may outlive my mind in a case like that. So you would actually be able to perceive yourself disappearing, because a person who is going into senility, they know that that's what's happening to them, at least in the early stages, right? So because of that, the idea that quantum immortality would apply here, or quantum torment would apply here, becomes a lot less obvious, because even the concept of a person starts to disappear as senility happens. The person might suddenly remember themselves, but they have no memory of the last five years, right? It's just complete amnesia of everything that's happened. And the dots aren't connected anymore. The memories aren't connected anymore. So you wouldn't necessarily be able to perceive quantum torment in a case like that, so [unclear: would/wouldn’t be possible on you]. By the same token, if you went out into outer space and you [jettisoned] yourself out into outer space, there's not some percentage chance you're going to live, right?

[00:37:53]  Bruce: It might as well be 100%. We can maybe talk about weird quantum events cause you to stay alive. Let me address that in just a second because it's actually an addressable case. The odds of you dying go to 100% and you're just dead, right? So you couldn't experience quantum torment in a case like that. So it doesn't even seem like... If you've seen Hitchhiker's Guide to the Galaxy where they have the infinite improbability drive where they shove people into outer space, that's actually why I'm using this as an example. And then the odds of surviving that are one in five trillion or something. And so they use the infinite improbability drive and they hit one in five trillion. And suddenly they've been saved. Right. And it's a big joke because, of course, Hitchhiker's Guide to the Galaxy is not meant to be taken seriously. There's not actually a reasonable chance that right after your spaceship explodes and you've gone to outer space that aliens are going to there come by and save you.

[00:38:56]  Unidentified speaker: Right.

[00:38:56]  Bruce: And that's the universe that you wake up in. Presumably, you're just dead as per the laws of physics in that case. So we can immediately see that there might be something wrong with the whole thinking with quantum immortality. However, these are the most extreme cases. What about a less extreme case? You're just living normal terrestrial life. You're getting older. You have a heart attack. There's some percentage chance that you wake back up again. Maybe in 90% of the universes you have a heart attack and you die. And in 10%, you wake back up again. You only perceive yourself in the 10%. You could keep playing that trick. And what you end up with is what this guy in this paper refers to as... He has names for the various other competing hypotheses. So he refers to quantum torment as the terrifying, terrifying corollary, as opposed to the comforting corollary.

[00:39:47]  Bruce: He says, OK, so the real truth is that the odds that you're going to actually be, you know, as you get older and as more bad things happen to you, the odds that you will not remember any of it, that you'll have amnesia, are much higher than the very, very low odds of having memories of it. So what you should really expect to happen in a case like this is that, yes, you may perceive yourself as living forever, but what you'll actually happen is that you'll, there'll be this big period of blank, and then suddenly you'll find yourself coming to, and you'll find yourself in a world where all your loved ones have died. That's bad. That's terrifying, maybe even. But suddenly the doctors are helping you, and you get to put yourself back into life again. By now— Who knows? Maybe the knowledge state is gone where they can reverse aging. And so even in a case like this where quantum immortality were actually being taken seriously, it doesn't necessarily follow that quantum torment would be the most probable outcome.

[00:40:51]  Bruce: And when you're trying to do this with branches across the multiverse based on probabilities, which is really just the percentage of the multiverse that that world is in, the expectation would be whatever is the highest probability. There may be some universe where there's some version of you that is in quantum torment, but that's a very improbable state. So you should expect yourself to instead find yourself in something more probable than that, which would be the comforting hypothesis. He gives several others that are slightly different from that. This probably gives at least the basic understanding of what he's trying to get to, that there's no particular reason why we should assume that the quantum torment state is more probable than some of these other states that we could imagine. So now here's the thing, though. This still strikes me as fairly terrifying, and he mentions that.

[00:41:39]  Bruce: He says, it seems like it would be better to just be able to die rather than to be forced to live in an aging body forever, even if they could have technology to try to help you. If you just couldn't perceive yourself dying, you would keep experiencing having all your loved ones die over and over again. It doesn't really seem like this would be a great state of living. And so while it isn't quantum torment, it isn't the hell of quantum torment, it still seems like it's maybe not a very good outcome. And he kind of leaves the paper like that. Does anybody read the paper differently than me? Peter, you read the paper, right?

[00:42:14]  Peter: Oh, yeah. I will say that I came away from it more convinced that this is a real concern. But, you know, I mean, the natural... It's kind of like what we were talking about before about Harry Potter universes and all that. I mean, is it really true that there's a universe where there's a caveman or a brontosaurus? I mean, you could go back. I don't know. That just doesn't seem right to me. But, you know, the basic idea, just to... Sorry if this is repetitive, but I just want to make sure we bring this home, is that we're at the end of our life, and the probability that we're going to die, it just keeps going up, but it never reaches 100%. So, you know, there's always going to be a branch of this unimaginably big multiverse where we are surviving. It seems to me the question the paper really tries to explore is this distinction between living and consciousness.

[00:43:21]  Peter: So, are we still conscious in these highly improbable events, or are we...

[00:43:29]  Bruce: Yes.

[00:43:30]  Peter: Consciousness is really what matters, I guess. I mean, you can be alive and not conscious, and it does kind of ring true that perhaps in this state of torment, we are not conscious, but maybe still alive. I mean, even that in itself, actually. Now that I say this all out loud, it sounds less probable than I was thinking five minutes ago, but I don't know.

[00:43:53]  Bruce: So, let me use the example of the pushing yourself out into outer space, okay?

[00:43:59]  Unidentified speaker: Yeah.

[00:44:00]  Bruce: So, we could argue you're going to die within seconds, right? But how long you're going to last out there in outer space is going to differ based on a series of quantum events. So, there's going to be some set of universes where it takes you two seconds to die, somewhere it takes you three seconds, somewhere it takes you four seconds, and it becomes less probable as the numbers stretch out. But there's always some universe where you perceive yourself living a bit longer. So, this is the strongest argument, steel man version of quantum torment that I can make, right? So, imagine then that just due to really weird quantum improbabilities, that you just do not die when you go out into space. And you just suffer in space, feeling like you're dying for the next billion years or until heat death is reached in a trillion years or something like that.

[00:44:58]  Bruce: You're just being tormented the whole time, okay? This is almost identical to the Boltzmann brain argument. In fact, it is the Boltzmann brain argument. And Sadia covered that well in the problem of physics episodes that we did. But the Boltzmann brain argument, you know what? Let me dive into this a little bit because I actually think this is really interesting. So we're dealing with really, really highly improbable events, okay? So there should be some universe where just by chance, atoms smash together and a copy of Peter appears in that universe, okay? There's nothing else in that universe except Peter. He's just in the void, right? And it's not just Peter's DNA. It happens to be the atoms smash together in such a way that it's a version of Peter that exactly remembers, has memories identical to the Peter I'm talking to right now, okay?

[00:45:55]  Bruce: So why doesn't Peter, at every single moment, suddenly find himself in the middle of quantum torment, in the middle of a void, right? Because there's some universe in which this is supposedly happening.

[00:46:07]  Peter: And you can think that it would be much more, at some level, that would be much more probable than the entire evolutionary history aligning just right to create my brain in this reality.

[00:46:18]  Bruce: Okay, so yes. So let me quote Penrose on this, alright? So Penrose, I found this really fascinating. I couldn't find all the quotes, so I'm going to have to go a lot off of memory. But Roger Penrose talks about the concept of entropy, okay? Now entropy is probabilistic. The current theory is probabilistic. It's one of the things that Chiara Marletto kind of criticizes about the theory and is trying to come up with a constructor theoretic version of it to solve that problem. But if you really think about it, like we say that we always move towards disorder, but there's some weird set of really improbable circumstances where like if I let a gas out into a jar, it will not stay up in the corner. Like I let it out and it's in the corner of the jar. It's going to slowly spread into a state of disorder where it's even across the jar, right? That would be just the regular second law of thermodynamics.

[00:47:18]  Bruce: But if I left that jar there forever, then just by chance, you would have some loop where all the particles go up to the corner of the jar again and then have to move back, okay? Because disorder is probabilistic, so there's always some chance that order will form just by chance, okay? So this is kind of where Penrose is starting with, is this idea that entropy is probabilistic. So he talks about, he's trying to explain how entropy relates to us. So let me see if I can find the quote here that I liked. He says, the question is, how do we keep ourselves alive throughout our normal, mainly adult lives? For that, we do not need to add to our energy content. So he points out that we often talk about how we need to eat for energy. And he's saying that's really not technically true, because our state of energy actually always stays the same. He says, however, you do need to replace the energy that we continually lose in the form of heat.

[00:48:15]  Bruce: Indeed, the more energetic that we are, the more energy we actually lose in this form. All this energy must be replaced. Heat is the most disordered form of energy that there is, i.e. it is the highest entropy form of energy. We take in energy in a low entropy form, food and oxygen, and we discard it in a high energy form, heat, carbon dioxide, etc. We do not need to gain energy from our environment since energy is conserved, but we are continually fighting against the second law of thermodynamics. Entropy is not conserved. It is increasing at all times. To keep ourselves alive, we need to keep lowering the entropy that is within ourselves. And we do this by feeding on low entropy combinations of food and atmospheric oxygen, combining them within our bodies, and then discarding the energy that we would otherwise have gained in high entropy form.

[00:49:03]  Bruce: In this way, we can keep entropy in our bodies from rising, and we can maintain and even increase our internal organization. Okay, so this is really why you need energy. It's really not that you need energy. It's that you need low entropy energy. So he kind of asked the question, where does this low entropy come from? Well, you've probably never thought of that before. You've probably always thought in terms of where does the energy come from? Oh, it comes from the sun. But what that really means is that the sun is in a low entropy state. It is in a highly improbable low entropy state. Now, so based on this, Penrose then tries to do a calculation, and he says, okay, just how improbable, if we just take entropy theory on its face, we're not using any other theory. We don't have any other theory we can reference here. What is the probability of our universe existing in the low entropy state that it's actually in?

[00:50:06]  Bruce: And he works out the math, and it turns out to be 10 to the 10th to the 123rd in 1 to 1 is the odds, right? It's a number. He says, this is an extraordinary figure. One could not possibly even write the number down in full in the ordinary [denary?] notation. It would be 1 followed by 10 to the 123rd successive zeros. Even if you were to write a zero on each separate photon, on each separate neutron in the entire universe, and we could throw in all the other particles as well for good measure, you would fall far short of writing down the figure needed. So the universe is in an incredibly improbable state, and we don't know why. It's a mystery, basically.

[00:51:01]  Peter: Now, Bruce, am I correct that he intended this as sort of a reductio ad absurdum, so it was supposed to be a thought experiment to illustrate how preposterous this is, but then some people seems like read it a little differently, like take it...

[00:51:18]  Bruce: So he's actually trying to build up to his own theory. So let me see, what was the name of his theory? Penrose, cyclic theory, the conformal cyclic cosmology theory. Now, he never actually gets there in the book I'm reading from. In this book, it's the emperor's new mind. He's trying to just prove that you can't build a computer that can think.

[00:51:40]  Peter: I'm sorry, when I said he, I meant Boltzmann. I got a little lost there.

[00:51:44]  Bruce: Oh, sorry. Okay.

[00:51:45]  Peter: That Boltzmann thought of it as more of a reductio ad absurdum.

[00:51:48]  Bruce: I think Boltzmann did. So let's work Boltzmann in here. So if the universe is in such an improbable state, Penrose points out that we don't need evolution, that the odds of the atoms smashing together into a Boltzmann brain that happens to be Peter with Peter's memories right now is far more probable, like way more probable than finding yourself in a universe that's in such a low entropy state. So based on that, and if we take that idea seriously, then we should all find ourselves in the state of quantum torment right now. Right? I mean, there shouldn't be a world where we're just living our lives. You can't explain our current experience trying to use this whole line of thought, because quantum torment should be the most common state. There's the atoms smashed together, Peter's there, he dies, then the atoms smash together, and by chance, it's the version of Peter that didn't die just before he died, so now he has to die again, and Peter lives forever in the void suffocating to death in quantum torment forever.

[00:52:53]  Bruce: Right? And this may seem like a reasonable argument based on what we're saying, but then why aren't we there now is basically what Penrose is trying to say. Right? And so there's clearly something just wrong with the whole line of thought, which is what you're saying about Boltzmann, right? He was trying to show that this is a ridiculous thing. I should probably point out, though, that the history of physicists trying to do reductio ad absurdum and then turning out to actually have made a fair point, like Einstein, he did the whole EPR paradox, and the point was to show that quantum mechanics was wrong. But today, everybody takes the EPR paradox as a serious outcome of quantum mechanics that is real, that has a real effect, precisely because we've now been able to go do the experiment, and we know it works, right? I mean, quantum mechanics actually does work, and Einstein was trying to show it was ridiculous, and it turns out it's not ridiculous, right?

[00:53:51]  Bruce: But yeah, physicists, and by the way, Schrödinger's cat was meant to show that quantum physics was ridiculous. But everybody takes it seriously today, because we don't really have an alternative explanation, so we have to take seriously the idea that a cat can be in a quantum state of dead and not dead at the same time. How you accept that and then not go on to buy many worlds, I don't know. I sat down with a physicist friend who teaches his students about the Schrödinger's cat, and will tell them the cat's in a state of being dead and alive at the same time, and yet he rejects many worlds. It's like, no, that is many worlds. You're there, right? Based on this, then, there's kind of this question of, is that really, why aren't we all just in the state of quantum torment all the time already? And if I knew the answer to that, then I would probably know the answer to do I need to worry about quantum torment?

[00:54:50]  Bruce: But I don't know the answer to that. There's clearly something more going on that just our current physics theories can't yet explain. Why are we in such a low entropy state? How did that happen? You know, it's funny, Penrose in one of the books, Shadows of the Mind, I think it was, he draws a picture of God putting the world into this really low entropy state to try to illustrate what he's trying to get at. So you've got this picture of God, like, sticking a pin into all the different possible states that the universe could be in and picking the one that happens to be our universe, and it's this little tiny point, you know, I thought that was rather humorous. So this is then kind of where we're getting to the end of what we can actually meaningfully say about quantum torment, quantum immortality. It's hard to know. In many ways, we just don't understand the theories well enough, and they may connect to other theories that we just don't have yet.

[00:55:52]  Bruce: And we're not quite sure what to make of it. Now, let me tie this now into where Peter started, because this is where the interesting twist comes in. I'm admitting my ignorance, and I'm admitting that we don't know, but just let's continue to—along the line of the thought of quantum immortality and quantum torment. Anyhow, let's accept it as true for the sake of argument. So which is more probable? Is it more probable that you will find yourself in a state of quantum torment, or is it more probable that you're going to die and wake up in the omega point, or an omega point-like cosmology? Quantum torment is such a hugely improbable state. It's exponentially growing every moment near the end of death where you should be dying. If there's anything like an omega point-like cosmology out there, it should be far more probable that you're going to wake up in the omega point.

[00:56:44]  Bruce: This is why the two concepts that we're talking about, the darker side and the lighter side of this, are actually all one thing, right? It's that in many ways, one of the best possible, most optimistic escapes from quantum torment would be omega point. That you can, in fact, see yourself dying, you die, and then the most likely scenario is that you wake up in the far future in a society that can reverse all the damage and can bring you back to life and you're going to be able to live a decent life after that. And they've got [unclear phrase] loved ones too, right?

[00:57:17]  Peter: But of course, bringing someone back to life based on their DNA is not really bringing someone back to life, right? I mean, because there's no memories.

[00:57:25]  Bruce: That's right. The way you would have to do it is you'd have to do something like Deutsch suggested, where you've got the technology to be able to simulate the entire universe or the multiverse. And then basically, in the simulation, you see when each person dies, and then you bring them into the Omega Point at that point. And so it wouldn't just be based on their DNA. That was Deutsch's version. Tipler's version was that there's only a finite number of, you know, the size of a brain. It's finite how large a brain can be, right? So there's a set bound, a C bound, or I forget what it's called, that determines how many human brains could possibly exist. So you simply instantiate all of them, and then everybody who has ever lived comes back from the dead, basically. So that's actually a lot easier than trying to simulate the entire universe. So there's more than one way you could go about this.

[00:58:19]  Bruce: It's way beyond our current knowledge or technology, but we can already see that it's at least a tractable problem, right? And with powerful enough computers and enough knowledge, in theory, you could do it.

[00:58:32]  Peter: And then if we're all universal explainers, why does it matter what our DNA says? I don't know, just something I just thought of.

[00:58:42]  Bruce: So, you know, it's interesting. There's actually maybe even a decent answer to that question. So we talked about in the last episode, Teilhard de Chardin and how he had this idea that we can take control of evolution. It's kind of the same thing. There's still a path that evolution sets out for us, that our DNA sets out for us. Who you are is largely made up by your genes at the initial state. As a universal explainer, yes, you can then make decisions that affect that. And in fact, in the end, with the right technology, which may be knowledge and technology that doesn't exist today, you can choose who you're going to be. Eventually, you'll be able to say, you know what, I don't like this aspect of myself. Let's even just say it is caused by genes. I have a genetic problem where I get too angry with my friends and I lose all my friends because of that, or I'm autistic, or just whatever you want to blame the genes for, whether that's accurate or not, I don't care at the moment.

[00:59:46]  Bruce: Eventually, the technology and the knowledge will exist where I can say, okay, I can overcome my autism. I can overcome my anger management problem. These are things that don't have to be with us forever. And at this point, whether the genes are causing it or not almost doesn't matter. Because in an ultimate sense, you could upload yourself into a computer with the right knowledge. You could then tweak your DNA as you see fit. You could do that with engineering. At some point, it doesn't not matter if the genes are causing whatever it is you don't like about yourself or not. You can make a choice to change it. So in the end, the genes can't possibly be the determining factor. However, let's say that Einstein's genes played a really big role in him being, and a lot of people think that he was like Asperger's or autistic or something, right?

[01:00:34]  Bruce: It's really hard to diagnose somebody who's dead, but there's some signs that that might have been a decent diagnosis for him. It's very likely that you need somebody who has something that we might consider a disorder to be able to think uniquely enough to come up with something like Einstein's Theory of General Relativity. In this sense, it might be a very good thing that the genes cause us to go down weird paths.

[01:01:01]  Peter: Oh, yeah.

[01:01:01]  Unidentified speaker: Oh, yeah.

[01:01:02]  Peter: The history of scientists who are probably on the autism spectrum is, I think, quite large.

[01:01:09]  Unidentified speaker: I mean, there's a lot.

[01:01:11]  Bruce: All right. That's actually... That's about all I think I know. Do you guys have anything else?

[01:01:17]  Peter: Take home point. I think maybe you'll agree with me that the optimistic version of the quantum immortality is much more plausible than the more pessimistic interpretations.

[01:01:30]  Bruce: I sure hope so.

[01:01:31]  Unidentified speaker: Okay.

[01:01:34]  Peter: Well, I'll go with that then.

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