Quantum Immortality

of religion and mythology. We've touched on it from the standpoint of our our great fear of mortality and death and therefore our longing for immortality and basically every aspect of our lives. And we have also talked about it a little bit in terms of improving human longevity. And I'm sure we've talked about it a good bit in reference to Highlander, because Robert, you've been watching that movie for about thirty five years, I think since you started

it in like three second increments or something. Yeah, I'm watching it on a streaming service in five to ten minute sections. It's a race against time to see if I can finish Highlander before it's removed from this particular streaming service. You know what they call that kind of lunch break, it's the quickening. I tend to call it a squatt and gobble because you're just kind of like squatting in your in your living room, just eating as fast as possible and watching just a little bit of

Highlander and then going back to work. Now, how does the Highlander version of immortality stack up against all the normal kinds of immortality you find in mythology and religion. I think you would probably agree with me that it's not the deepest treatment of immortality and mortality in in in our collective storytelling. But it does hit on some of the main points, right, Like, oh, immortality sounds great, but then when you actually have to do it, it's kind of a pain. Um. Well, I'd say a lot

of religious visions are actually like that. They tell you, you know, a lot of religions include some version of immortality, whether it's a sort of linear survival after death of the soul, or there's a kind of eternal cycle of reincarnation or something like that. In any event, it very often is not necessarily encouraged for you to look too

closely at the details of immortality. Right, But this Highlander is essentially another version of the wandering immortal story where they're kind of stuck with it it what seems like it would be a blessing is kind of a curse. I feel like human perceptions of immortality, they tend to break down to this imagined things that would normally terminate or undergo a phase shift but magically don't have to.

So the desire to for immortality is often either a reaction to just the reality of death and mortality itself, which is very understandable. Uh, kind of defines our existence is modern humans, or it comes from a desire for a certain state of existence to continue unchanged. But it does often kind of come back to this idea of stagnation, you know. Um, Like the thing I want is really stagnation.

The thing I'm afraid of is change, um you know I and I wonder if if that's what we see in Highlander, you know, in these characters like Connor McLeod and Ramires. You know this Connor changed? Is he changed by his experience in the film? I mean certainly that the Kurgan, the villain isn't. Um. It seems like it would be more interesting if you like switched around backgrounds and had like the Goody two shoes becomes the villain and the and the the ancient villain becomes the modern hero,

that sort of transformation, but instead these are very stagnant characters. Well, it's actually part of the ancient mythological tradition of immortality that if it comes with too much change, it's actually a curse rather than a blessing. Uh. Think about Aos and Tiffannus in Greek mythology. We we've talked about them recently or where the ideas Aos, the goddess of Dawn, has this lover, this mortal human lover named Tiffanus, and

she wants him to be able to live forever. So she cries to Zeus and says, please grant him and more to Lity, and Zeus, being the jerk that he has, says, okay, done, makes Tiffanness an immortal, but doesn't grant him eternal youth. So he's gonna live forever, but he's just gonna get older and older, and that seems to be implied to

be a fate worse than death. Yeah. You know another treatment on this that I really like Richard K. Morgan in his book Altered Carbon uh, and then also in the Netflix series that just recently came out, that that is basically that first book brought to life on the screen. In this show, you have essentially immortality via digital consciousness, digitized human consciousness moved from body to body, and typically you have a very grim vision of what that would mean.

It basically means that the the worst, you know, richest decrepit individuals in society, they're just gonna grow more and more awful because they have more they have an increased lifespan in which to be awful and become jaded to their various uh um, you know, inappropriate pleasures. Yeah, we have a concept that the elderly tend to become wise in their old age. I mean, who knows if that's actually true, but well there's at least an impression along

those lines. But it seems to be premised on the knowledge that death is coming. What if wisdom is contingent on that. Yeah, it takes me back to our episode on Chinese immortality and some of these Dallas concepts of like the the elder enlightened being where you're aging is a transformation into a different state. But so many of these ideas of immortality, it's like, yeah, you get to remain young forever, uh forget without really thinking about what

that would do, how that might warp the individual. But what if there was a concept of immortality that in fact didn't imply any of these changes, right. It didn't say that you're going to make a phase transition to another kind of being. It didn't say that your soul is going to leave your body. It didn't say any of that. It was just a literal, physical, straightforward statement that everything is going to be normal. There's no magic, except you'll just happen to never die. What sounds good

is their catch, Whether or not it sounds good. This is what we want to talk about today, a physical possibility of immortality presented as a thought experiment with a lot of perhaps flawed underlying assumptions. So you're unfortunately not going to walk away from today's episode probably with the assumption that yes, all humans will live forever based on the laws of physics, but we do want to explore

that as a possibility. Yeah, nothing we're going to talk about here today is actually going to impact your life, except in the way maybe you think about your existence. Quite true, unless it does impact your life, in which case this is going to be very important. We're barely talking about quantum mechanics, and it's already tangled up it or not here, right, So we should make the transition to talking about physics, because this is going to be

a physics spaced episode talking about interpretations of quantum mechanics. Uh, and so I guess we should begin with just a little bit of the discussion of weirdness of scale sale. If you listen to this podcast, you've probably heard at least a little bit about the deep strangeness of physics at scales much bigger or smaller than the energy, mass, distance, speed, and so forth that we deal with on a day

to day basis. On, for example, vast scales, we live in a universe apparently dominated by dark matter, these gigantic gravitational anomalies that can't be seen or touched except by the way that they've been space time and hold galaxies together, and on these huge scales, the dominating physics regime, the kind of physics that makes the biggest difference is not the kind of physics that governs our everyday lives, but of Einstein's general relativity, where time is not a universal

measure and can appear to slow down or speed up from different vantage points. Where mass changes the geometry of space time itself and can warp or even trap light itself. Now shrink down to roughly human sized scales, and suddenly the laws of physics appear or to change. They don't really change, but different physical phenomena become the most salient, become the most important types of calculations to do when you're trying to figure out how things are moving and

how one physical thing is affecting another. So this normal scale, general relativity doesn't matter very much. We can throw baseballs and shoot cannons and smash watermelons and all that stuff without taking general relativity into the equation. And this scale is generally best described by Isaac Newton's classical mechanics. This is also the realm which physics is intuitive. Right at this scale, everything seems to fly and fall and push

and resist in a way that makes sense to us. Yeah, this is the This is the room in which we we have evolved to thrive exactly. That's the important point. It's kind of hard to remember this, but we should do our best to internalize the fact that this middle scale of physics, the Newtonian scale, does not actually make any more sense in an objective point of view than the other scales do. It's just the scale at which

our brains evolved. So presumably, if we happen to be evolved star sized organisms, things like general relativity would be intuitive and would make natural sense to us, and Newtonian physics would be crazy, weird stuff that goes on down there. Well, one way that I like to think about it is the explanation that you can think of classical physics as the Earth's crust and quantum physics as the underlying mantle, and then you have to keep in mind that there

are things about Earth's mantle. They only make sense if you take into account Earth's in our core. I think that's a good analogy, because if we do keep zooming down, we of course get get to what you just mentioned,

quantum mechanics, this next realm where things change. Yet again, you get too extremely small scales on the scale of elementary particles and tiny objects like atoms, protons, electrons, photons of light, and at this scale the physics regime changes so that things stop behaving in a way best described by either general relativity or classical mechanics, and they int behave according to a theory we now know as quantum

mechanics or quantum physics. And this came about because, you know, originally, say the dawn of the twentieth century, scientists were trying to figure out how things like atoms could behave as reconciled by classical mechanics. They were trying to look at things like the orbit of electrons around the nucleus of an atom and say, okay, does that work in a classical mechanics way, like the way planets orbit around a star,

And it just didn't work. So they had to figure out what's actually going on here, and eventually they came up with the theory of quantum physics, which is now predicted mainly by what is called I've been saying his name wrong my whole life. I think that the Shreddinger equation. I've been calling him Schrodinger. I've been saying Schrodinger as well. I feel like I've heard Schrodinger from everybody. Yeah, I think I've heard it, but I don't know. I think

shredd Shreddinger is shredding. It's hard to even say. I want to go Schrodinger Shreddinger. It's all because of Shreddinger. It does it sounds more wholesome than than than cats and boxes, uh, than that are neither dead nor alive, or are both dead and alive at the same time. Yeah, so, well, you'll probably hear us say it both ways in this podcast. I apologize for that, but there's gonna be just no getting around it. I guess it depends on how the

wave function collapses each time, but um so anyway. It is named after the Austrian physicist Irvin Shreddinger, and Shreddinger derived the equation in the mid nineteen twenties and ever since then it has been profoundly useful and profoundly confusing. And this is because quantum mechanics is simultaneously one of the best most predictive theories in all of science, and at the same time it clearly implies a reality that makes absolutely no intuitive sense to us mammals that evolved

to deal with classical physics on the Newtonian scale. It is bonkers and completely defies our expectations of how the world should work. And there are a bunch of different ways you could explain this, but just to pick the simplest version for now, that the Shreddinger equation can be used to predict the behavior of tiny particles like atoms

and electrons over time. So just the way that you can use Newtonian equations to predict something like the arc of a cannonball or the force of a falling boulder, you can use the Shreddinger equation to predict the behavior of tiny particles like electrons or photons. But a Newtonian cannonball is experienced by us and described by physics as a single solitary object with one starting point a single

ending point in a clear trajectory. A particle on the quantum scale does not behave that way at all, but rather, according to the shredding Ear equation, it behaves a lot like a pattern of waves in a fluid, and this means it can have what can seem like multiple contradictory properties. For example, a particle can, from our point of view, appear to have multiple different positions, velocities, or spin directions at the same time. And this range of possible simultaneous

behaviors is what's known as the wave function. The wave function is all of these potentialities that seemed to be simultaneously true about a quantum object or system, and this wave function exists in an abstract infinite dimensional space that's known as the Hilbert space. Now again, of course this makes no sense to us, but it's proven to a degree that's almost beyond dispute. Like one of the most classic proofs of the wave function behavior of quantum scale

objects is the double slit experiment. Yes, this is where we get the same. When you're out of slit, you're out of peer. Right now, that's a different situation. I don't know what you're talking about. Old beer ad slit speer sla. We've actually just been looking at old beer ads here on the podcast. There apparently was an old Miller ad that had gigantic monsters in it where they grab a truck full of miller and just chugged the truck. Yeah,

now that one's awesome. I think that was that was from from when I was a kid, or in junior high or something. I remember seeing that one, the Schlitz beer ad where they have this whole when you're out of slits, you're out of here. Uh, it's one I never actually saw, but was referenced on Mystery Science Theater three thousand. Growing up. So one of these these these many pop culture references that I have no direct experience with,

only a secondhand experience with them from watching MST. Isn't it sweet that all of these beer commercials are imprinted on your childhood? Yeah, well it's some of them were not too bad. Some of them had monsters in them. But the double slit experiment to get to get it back to quantum mechanics here, the basic idea is pretty simple. The experimenter shines a light on a barrier that has two narrow slits in it, and then the experimental studies

the interference pattern produces on a screen. So you've got like two walls in order, and the first wall that the light has to go through as the two slits, and then the back wall has a screen on it that the light can be projected on after it goes past the first wall. Right, And I should also add that this was first performed by Thomas Young in eighteen o one. Now, light has a dual nature, it's both wave like and particle like. In the experiment, light travels

through both slits and creates this interference pattern. And if you send a single photon through photon being the light particle, right, the single unit of electromagnetic energy. So you send a single photon through it still forms an interference pattern as if the single photon travels through both slits simultaneously. If you hear me laughing, it's because at this point in our notes, Robert has inserted an image from the movie Time Cop two of what actor Ron Silver, Yeah, he

played the villain. And here we have two different the villain from different time periods encountering each other and kind of looking at each other with amusement and or confusion. And I think both of these responses are are apt when contemplate and quantum mechanics. I mean, basically, though this is a simple experiment. Who observes something that should not

be at least as far as classical physics is concerned. Yeah, the the idea that at the quantum level, a single object can appear to inhabit multiple places at one time. It produces this wave of like effect when it should be more like, you know, we think on a classical level, would be like a ball thrown at something. It's one object, but it's not. And you have to wonder how can this be true? Like objects in our experience never appear to be in more than one place at one time.

A baygel does not behave like a wave pattern in which you know their peaks and troughs at different locations. Right. A bagel is just a single solid object that doesn't move unless you move it. Yeah, I think, I mean we we we mentioned time cop in passing here, and I don't think a deep scientific reading of time cop is is essential here. But this in other films do kind of get into this territory when you have the paradox, right of of the same character encountering themselves from a

different time. Um, well, anytime something that is I mean, how can that be, right, something somebody is in two places at once. Yeah, it's used in fiction because obviously it never happens on a macroscopic scale and reality. So the contradiction here is between the fact that the Shreddinger equation is obviously correct and the fact that it predicts stuff that makes no sense and we never see. And so it's led to the need for what are called

interpretations of quantum mechanics. Pretty Much everybody accepts the underlying theory of quantum mechanics. You'd be a fool not to. It's incredibly experimentally verified and very predictive, but there's a lot of disagreement about what it means and how it actually connects to our experience of reality. So, Robert, you mentioned the dead cat in the box earlier. Yes, this is going to be a feature of what's been for

a long time the leading interpretation of quantum mechanics. So you've got different interpretations that we're going to talk about two mainly today, but there have been actually a bunch of different interpretations. The two we're gonna be focusing on are the Copenhagen interpretation and what we will later discuss

as the many Worlds interpretation. But the Copenhagen interpretation was created in the nineteen twenties by the physicist Nil Spoor and Werner Heisenberg, and the Copenhagen interpretation essentially postulates a world governed by quantum mechanical probabilities, and these probabilities get decided on through a process known as wave function collapse. So you've got these multiple possibilities at the same time. That's the way of function. Uh. And then they're going

to say it collapses, So what does that mean? So imagine you've got a quantum level particle like an electron, and you're trying to figure out where is it going to be? Is the electron going to be on the right or is it going to be on the left. What the Copenhagen interpretation says is that this wave function is in a state of unresolved potential called superposition, and the electron could be on the right, and it could be on the left, and in fact it's neither one.

But it's in this state where there's a fifty percent probability of each And here's where it connects with our world of solid macroscopic objects that are in only one state in one place at a time. The Copenhagen interpretation says that the wave function collapses into only one of its potential configurations once somebody observes it. Now, this has led to a lot of people reading all kinds of crazy esoteric things about consciousness into quantum mechanics, right right, Yeah,

basically what is the role of the observer and everything? Yeah, But I think a lot of those, uh, those consciousness type ideas are based on a misinterpretation of the grounding of the Copenhagen interpretation and a misinter misunderstanding of the fact that the Copenhagen interpretation is not a sure thing

that it is an interpretation, not the theory itself. But this is again, this is where the cat comes in the idea that the cat is simultaneously dead and alive inside of this box where where random life or death is going to occur. Right, So that, yeah, this is going to be how they map it up from the quantum realm into the macroscopic world and how does our reality connect with these probability distributions on the quantum level. Uh, So,

you've got an electron. It's neither on your left nor on your right, but in a state of superposition where there is simultaneously a fifty probability of finding it on each side if you look with precision, and it just stays this way, suspended it with these possibilities until somebody observes it, meaning you use some kind of device or method to figure out exactly where that particle is. And then the once somebody does that, then it's actually only

one place it was in superposition. Then you looked at it. Now it's on your left. It's not crazy. That crazy situation to to really wrap your head around. If you sort of think of it in terms of like TV production or something. You know, if you're on one of these shows, we have to guess what's behind the curtain, and there's something behind each curtain, but only one curtain is actually gonna be opened. Oh yeah, and a kind

of solipsistic way. It's almost not hard to believe that the universe only only matters when I look at it. But yeah, So, despite the fact that many physicists have felt fine relying on this interpretation for the decade since then, I mean, one thing we should point out is that you can do all kinds of useful quantum mechanics science and and even use it for technology without knowing which interpretation is correct. And in fact, it sometimes doesn't matter

which interpretation is correct. The math of the theory works either way, right, Yeah, absolutely, But many continue to protest that the Copenhagen interpretation is nonsensical and it leads to these apparent absurdities like as as you mentioned, Robert the cat in the box, the famous Schrodinger's cat or Shreddinger's cat. Yeah, we've we've already referenced a couple of times. You should probably just lay it out for us here exactly how this experiment goes. Uh, However, you know I do have

a soft spot for cats. Yeah, let's let's get rid of cats. Don't want to kill a cat again. We people talk about killing cats way too much in science. Maybe they're anti cat. I'm going to bring in a unicorn because we've established that maybe unicorns aren't as perfect as everybody thinks they are. This particular experiment funded entirely by Tim Curry, Lord of Darkness. Full disclosure. Okay, so I've got a unicorn in a box. This box is

totally opaque and nobody can see what's happening inside. There no cameras inside. You don't know what's going on there. And there is a device inside the box that will instantaneously incinerate the unicorn if it's triggered. And the device gets triggered based on a quantum superposition event. So there's a particle that has a fifty chance of spinning clockwise and a fifty chance of spinning counterclockwise. And if when you check the particle, it's spinning clockwise, the unicorn dies,

and if it's spinning counterclockwise, the unicorn lives. But this would mean that the unicorn is both literally alive and dead at the same time inside the box until somebody looks inside the box to observe what happened. And at the moment somebody looks inside the box, then suddenly the unicorn is actually just either alive or dead, but until somebody looked, it was both. Robert, do you think that describes the universe we live in? Um? I don't think it.

It does not really describe the universe that we perceive. That's the thing. Yeah, the universe we live in is vast beyond our abilities to process it. Yeah, so yeah, it's the answer is kind of yes and no at the same time. I mean, I feel kind of despose. Again, we want to be clear that we think the universe does not need to adhere to our intuition. So just the fact that something seems unlikely to you or to me doesn't make it actually unlikely to exist in the world.

But just going on a gut level, one does has come to feel less and less right to me, And so I'm kind of disposed against the Copenhagen interpretation. I think all that means is that it doesn't necessarily feel

right to me. That doesn't mean it's not true. I feel like it lines up well with like with with with personal anxiety, you know, because it's essentially because when when you're anxious about the future, you the bad things that can happen are as real as the good things or just the mediocre things that could happen, and the bad thing is only really gone when you actually reach the point where where the particle has spun left. You know.

So there is something about about the about this particular explanation that I think does match up with some of the ways we perceive our world. Yeah, definitely lines up with some emotional realities. Maybe less so with physical objects. Definitely. Uh so, yeah, well we'll see. I mean, again, we can't rule it out. It it's still been the the interpretation that's been fa by the majority of physicists since

the advent of quantum mechanics. But like we said earlier, it's not the only way, And to get to our discussion of physical immortality, we're gonna have to explore another interpretation of quantum mechanics that arose in opposition to the

Copenhagen interpretation. We will start looking at that when we get back from a break than alright, we're back, so we're gonna start talking here about the many worlds interpretation, which I believe we've we've probably touched on on the show before, because it is one of these that spins off into very uh fantastic comic book realms, right, the idea of alternate realities, other worlds where other things have happened, essentially the Library of Babble, yes, but with a specific

physical mechanism causing it to come into existence. And so we will do our best to try to explain this here. Now, we've been talking about the Copenhagen interpretation, the idea that you've got a quantum mechanical system that's in superposition sort of both in a simple way, it's both left and right literally at the same time until you look at it, at which point it becomes just one or the other.

And so observation causes the collapse of the way of function, and it just becomes a normal physical reality, just like the kind of single, solitary reality that we're used to looking at. Here's the main difference between that and what we're about to talk about, the many worlds interpretation. In this interpretation, a particle does not exist in superposition between two possible outcomes and then collapse into one. Outcome or

the other. When we look at it instead, it exists as a wave function in this superposition where there it has multiple different qualities at the same time, it's both left and right. It's in this state as a wave and then it stays that way, and it just keeps staying that way, and that's how it works. So it's another way the bad thing that ends up not happening actually does happen, but it's in essentially another timeline. Yeah,

pretty much. So this was first proposed by the physicist to you ever at the third when he was a graduate student at Princeton in nineteen fifty seven. And it's not the core of the theory that there are multiple universes, but you cannot deny that. When you take this theory to its logical conclusion, it puts us in and a multiverse of infinite timelines, right, infinite timelines, infinite parallel universes,

each different from the last. Now, and some of these universes, it again comes right back to basically what we described in the Library of Babel, and some of these universes, the difference is going to be really slight, such as a parallel universe where everything is exactly the same, except you had a bagel for breakfast instead of cereal. Um. Then there's also one, for instance, there's a universe where

Highlander one Best Picture of the fifty nine Academy Awards. Well, now I want to take issue with you there for a second. It predicts that you could possibly have every variation on the universe that is allowed by the laws of physics. I'm not sure if the laws of physics rule out to Highlander best Picture win. Well, there's papers will have to be written about that, so we'll have we'll have to see some peer viewed papers on that

that question, Joe. Basically, the idea, though, is for each possible outcome to a given action, the world splits into copies of itself, instantaneous processes that Everett calls decohesion. But before I move forward on on the oscars, I guess a better argument would you could say that there's a version where that year the Academy awards Children of a

Lesser God one as opposed to Platoon, which actually won. Yeah. Well, I mean, so what it would actually mean is that the outcomes of these universes split every time there are different possible branches of a quantum superposition. Now, the question would be how often are differences in reality determined by

a quantum superposition going into its different possibilities. Presumably the answer to that is a lot, because I mean, quantum mechanics underlies all kinds of stuff that's happening all the time. It underlies things that are happening inside people's brains, It underlies things that are happening in physical reality and the

interactions between objects. Small random differences in how a quantum superposition event breaks off could lead to macroscopic effects down the line, and some of these effects could be rather severe. So you could have other universes which would differ in ways that alter reality on a grand scale. For instance, imagine a parallel universe with no gravity um. Some cosmologists use the theory is that handy explanation for why life

evolved in our universe at all? Their answer is simply, well, they're ac countless universes where life never evolved, and various universes in which it evolved along similar lines as ours.

It's kind of a way to get around the Copernican principle, right, the idea that Earth and and therefore earth life and the human experience should not have a privileged position in the cosmos, right, Uh yeah, I mean it's essentially that's sort of anthropic reasoning, the anthropic principle like why do we live on a planet that's capable of supporting life? The idea under that is like, well, where would you expect to live? Would you expect to live on a

planet that couldn't support life? Um? Yeah, And there are a lot of interesting questions about whether that type of reasoning is valid or not. I'm not up. I used to read about this kind of stuff, but it's been a while since I did. Well, it's it's like, how how is it possible that I'm alive and I haven't been killed by Jason Vorhees. Well, there there are multiple alternate realities where I have But where else could I be thinking about this at this point in my life

than a universe in which I have not. Now, that kind of reasoning will come up again in a big way in a minute. So we should be clear that the existence of possibly infinite parallel universes is a consequence or an implication of Everett's interpretation of quantum mechanics, not the core assumption of it. The core assumption is just the universality of the wave function. It just says the wave function is real. All of the different possibility of

the wave function are real. They actually exist, and they never collapse. But Everett believe that if you follow the logic, if you extra polate that out to the macroscopic scale that we live on, the only way to make sense of it is that bifurcating realities constantly split off from one another and exist independently. Uh. And just just a

few interesting biographical notes. Everett recounted in the nineteen seventies that the many World's interpretations sprang up one night when he was talking with a couple of Princeton classmates about the implications of quantum mechanics. It was quote after a slash or two of sherry, And that seems kind of right, right, Like, the many worlds interpretation has got to be a sherry based interpretation. It is like, not a vodka based interpretation.

Nor is it a beer induced interpretation. Yeah, it does. It does sound like the sherry is essential here. Yeah. And another thing that's essential is the simplicity of it. Right. The core selling point of the many worlds interpretation is that we've tested the mathematical reality of quantum theory. We pretty much know it's right. So what does the math say.

Despite how outlandish the physical implications of the many worlds interpretation seem, you can make a pretty strong argument that it is the simplest possible interpretation of the math of

quantum theory. If you just look at the mathematical features of the way of function and you try to take away all your intuitions about how things should work, it's the simplest possible way to make sense of it, and about it being the simplest theory Evert actually wrote in a letter to the physicist Brice de Witt in nineteen seven, quote, I do believe, however, that at this time the present theory, meaning the many worlds interpretation, is the simplest adequate interpretation.

The hidden variable theories are to me more cumbersome and artificial, while the Copenhagen interpretation is hopelessly incomplete because of its a priori reliance on classical physics, excluding in principle any deduction of classical physics quantum theory, or any adequate investigation of the measuring process, as well as a philosophic monstrosity with a reality concept for the macroscopic world and a

denial of the same for the microcosm. So that's kind of a strong argument he's saying, right, like the Copenhagen interpretation says, Oh, yeah, the macroscopic world is real, but there's something about the quantum realm that isn't as real as our world is. Yeah, it kind of relegates it to like a ghost realm. Yeah. One of the books we're going to be referring to in this episode is Max tag mark book Our Mathematical Universe, and tag Mark

writes about de Witt. He says, quote, when I later met Bryce, he told me he'd at first complained to you Everett, saying that he liked his math, but was really bothered by the gut feeling that he just didn't feel like he was constantly splitting into parallel versions of himself. He told me that Everett had responded with a question, do you feel like you're orbiting the Sun at thirty

kilometers per second? Touche? Bryce had exclaimed and conceded to fee done the spot just as classical physics predicts that we're zooming around the Sun and we won't feel it. Everett showed that collapse free quantum physics predicts that we're splitting and that we won't feel it now, despite the fact that it does seem to make sense to a lot of people now. Unfortunately, it did not catch on

in Everett's lifetime. When the Copenhagen interpretation remained dominant, and Everett was reportedly bitter about academia's rejection of his work, he left academic physics. He went to work at the Pentagon, where he was apparently involved in some Cold War nuclear strategy, and over time friends and colleagues reported that he had a lot of bitterness and negative affect and that he also struggled with alcoholism, and he eventually died pretty young. He died at the age of fifty one in nineteen

eighty two. And just as a side note about his family, one of Everett's children is actually Mark Oliver Everett, who's the singer of the rock band called Eels. Interesting, well, it makes me wonder if he has any songs about his his father. Yeah, he apparently does, as Actually I haven't listened to them. I haven't listened to a lot of Eels, but I remember I remember getting some mixed CDs when I was in high school that had some

Eels songs. Eels fans will have to chime in and let us know, Yeah, let us know what we should listen to. But anyway, since Everett's death, the many World's interpretation has gradually become much more popular. Actually, the Polish American physicist of void check Zurich, has said, quote Everett's accomplishment was to insist that quantum theory should be universal, that there should not be a division of the universe into something which is a priori classical and something which

is a priori quantum. He gave us all a ticket to use quantum theory the way we use it now to describe measurement as a whole. So essentially, it's a way of looking at quantum quantum theory and saying, no, it's all real, it all works, and it totally applies to the universe as a whole. It's not some weird special realm that we have to invoke strange types of

causation to understand. But here's the question. If it's true that the wave function is real and universal and it's reality has effects that hold sway over the macroscopic world, that the world we live in. What does this mean for us? What should it be like to be a

person living within a mini worlds universe? Yeah? Because it seems like, Okay, it's one thing to say that every time I make a choice, the timeline splits, but I still I still feel like I am an object moving along a timeline, even if even if I'm splitting, I have this singular experience unless I'm bringing in some sort of uh you know, magical, uh you know, religious idea of what my my, my consciousness is doing in other lives. Yeah, I mean we we can't have access to that, right,

And here's actually the question. Here is the really interesting question. Why don't we have access to that? Right? What is actually happening in the physical realm? If the Many World's interpretation is correct, what is actually happening that puts those in another place and keeps you separate from them? Which is essentially the same as saying why does the wave function branch into separate realities? And the answer, as best I can tell, appears to lie in a quantum physics

concept known as decoherents now. I mentioned earlier that Max Tegmark book that our mathematical universe, and he has a pretty good discussion of decoherents in his book Um. But basically, the way it works is this, as long as a quantum system in superposition remains physically isolated, all of its potential states can continue to interact with one another. But systems, of course, almost never stay isolated for long. I mean, how often would you expect a system in reality to

stay isolated from any contact with the outside. If even a single photon from the outside of the system interacts with it, then the system undergoes what's known as decoherence. We mentioned this concept earlier, which means that it's potential states can no longer interact with each other. If they can know longer interact with each other, they essentially branch off.

They become causally separate timelines, whereas before they were intertwined. So, in a basic sense, imagine you've got an isolated quantum system where you've got a particle on the left and the right at the same time in superposition. But if anything touches it, decoherence happens, and then it splits into different branches of the universe that can no longer affect one another. Thus, the wave function does not collapse. Decoherence

just prevents these branches from messing with each other anymore. Now, we teased at the beginning that this would be coming to the concept of immortality. How do you get immortality out of any of the physics concepts we've been discussing so far. Well, I know the answer to this question, and I'm still not convinced that you do. But um, But basically, and you're gonna have to pull out a thought experiment. Yeah, and you're gonna have to have a machine.

And as it seems to be this the running trend with with quantum mechanics thought experiments, it's going to somehow involve lethal violence. Yeah. One way this has been described we're about to get to something known as the quantum suicide experiment. And one way this has been described as Schreddinger's cat. From the cat's perspective, you make yourself the cat.

So several physicists, apparently beginning with two independent lines of work by Hans Morevac and Bruno Maschaal in the nineteen eighties and then later by Max tag Mark, have proposed an apparently ingenious and perhaps flawed way to test whether the mini worlds interpretation is correct, and how that would affect personal subjective consciousness. We do not recommend this method at all. You should not try it out. But here's the method that's been described. You have to build a

machine that will kill you. All Right, we're gonna take a break and when we come back, we will assemble this machine or a version of this machine than alright, we're back. So we've been discussing how the man world's interpretation would affect the subjective experience of life and death. And there has been a type of experiment proposed by some physicists to test for the reality of the many worlds interpretation by experimenting with one zone life and death

subjective experience. This is known as quantum suicide or the quantum suicide experiment. Now, Robert, you have come up with a a more a more fun version of this experiment than the usual one. The usual one involves creating some kind of gun that is designed to shoot you or not shoot you, based on a quantum event. Yeah, and this is this is max tech marks uh concept. Right, there's a there's at you said a machine gun in

the original version. Yeah. He so he's got the idea of a machine gun that that has a trigger pull that's initiated by a potential quantum superposition that could go one way or could go the other. Like, You've got a particle that could be spinning right and it could be spinning left, and it's got a fifty percent chance of being either one. And if you check it and it's spinning right, the gun fires, and if you check it and it's spinning left, the gun does not fire.

And it does this once per second. And then he says, the test is you put your head in front of the gun. Yeah, that's just I don't know, it just feels a little too too violent um for this podcast for some reason. So I thought, yeah, let's let's try something maybe a little more science fiction, a e uh in nature, a little less gun centric, and maybe a little more Dune inspired. Uh So, my apologies to to Max for for alterations here. Also, I guess, you know,

apologies to Frank Herbert as well, just in case. But this is this is how it's going to roll out. We're gonna take you through the experiment. You're gonna start with a man or a young man. This is gonna be polo trades right essentially. Yeah, you can Okay, you can essentially think of it as polo trades and uh, he's gonna sit before a machine, a non thinking machine,

mind you. This is designed to jab him in the arm with a meta cyanide poison needle, a k A M jabber based on the spin of a quad un quantum particle, so that gom jabber hits him, the jabber. It's gonna be instant death, just no no chance, okay. And it is instant. He won't even know it happened. Right. So the machine again is gonna gonna look at that quantum particle and and study its spin. If there's a clockwise spin on the quantum particle, then the gob jabber

is gonna strike. If there's a counterclockwise spin on the quantum particle, the gom jabber just buzzes, threatening lee. The young man here keeps pushing the button and the gom jabber buzzes, buzzes and buzzes, but it doesn't move. Each time he pushes the button, it buzzes, but it doesn't strike. Well, yeah, so what's happening here in this experiment? As you can tell,

the experiment has a probability based outcome. After the first button push, there's a fifty percent chance that Paul is Paul will live in a fifty percent chance that he's going to die, and then this repeats. On the second try, there is a cumulative chance that he'll live, and by the third try half of that, and it just keeps going down until probability virtually guarantees that Paul Trades has

been struck dead by the gom Jabber. But from Paul's own subjective point of view, this experiment actually might have a very different flavor assuming, and there are some assumptions underlying this, assuming that consciousness ends immediately at death. Now, of course, if consciousness survives death were obviously in a whole different ball game. But for Paul himself, there is only one option for Paul to discover. After each push

of the button, he discovers he has survived. If the gom jabber strikes and he's instantly killed, he will never be aware of it. But in a universe in which the Many World's interpretation is correct, there is no opportunity for him to be the one who dies, since his subjective experience of those branches of the wave function does

not exist. So if Paul is any thing, he can only be the version of himself that survives, and thus, if he starts performing this experiment, the only versions of him that exist to continue the experiment will be the ones that continually route his consciousness into branches of the way of function in which he survives. So he'll just keep pressing the button over and over and over again, and the only thing he'll ever experience is survival and

this will happen an infinite number of times if necessary. Yeah, now, what are the drawbacks to this experiment? Well, there are obviously theoretical objections to the validity of the experiment, reasons to think that even if the Many World's interpretation is correct, the experiment wouldn't actually work, and we can explore those

in a moment. But on top of that, there are some big problems, like you have to be willing to kill yourself, and you can never use this test to prove the Many World's interpretation to people other than yourself. It's not actually a scientific experiment because a scientific experiment needs to be able to be objectively verified, and this is experiment that, by necessity can only be subjectively verified. Even if it works as proposed, it would only be

valuable to you yourself. The vast majority of people throughout the quantum multiverse watching you perform this experiment will just witness you killing yourself on the first try, or the second try, or the third try, and so on. And each time you press the button, a greater proportion of the people watching you throughout the quantum multiverse will just be watching you kill yourself. Plus, it's a perfect waste

of a good con jabber, in my opinion. Now, assuming for a moment that the logic of this experiment is valid, and there are potentially strong reasons for thinking it's not, but just go with us for a second, it gets weirder because let's extend the reasoning beyond the confines of the experiment. Here are a few thoughts to consider in any dangerous real world situation that might lead to death.

Whether you maybe just got a blast of neutron radiation in the face, or somebody tries to drop a garbage truck on you from a great height or whatever, there is always a small chance that something will happen to prevent you from dying. Would you agree Robert with me so far? Yeah, I would say, broadly speaking, that's true. It might be a very small chance, but there's always a small chance Superman could appear and jump in front

of the bullet of the train it set. Well, okay, maybe not that, Maybe not that, because we don't want to violate the laws of physics. So there's always a small chance that without violating the laws of physics, something will happen to prevent you from dying in this scenario, right, there's always some sort of freak occurrence that could prevent

it from happening. Yes, yes, So if there's a chance of survival that's consistent with the laws of physics, there's at least some branch of the universal wave function in which that chance becomes reality. So at some level, all threats to survival are quantum threats, and thus, if on these assumptions, if the Mini World's interpretation is correct, you should always expect to continue surviving, no matter how improbable the odds, because subjectively you have no choice but to survive.

If there is anything that you are, you are the version of you that has survived, and so the vast majority of the versions of you throughout this quantum multiverse will die, but the subjective version of you will always live on in the branches of reality that break in favor of your survival. Now again, just to clarify, we're not advocating this as necessarily the truth about reality. But if you consider this this is a possibility, it is

very strange to contemplate, right, Oh yeah. And I mean the thing is, though, I always wonder what stuff like this. Are we really talking about immortality here or just a mere thought experiment variant. It's kind of kind of worthless when you really think about it. You know, well, what do you mean by that? I mean, well, simply, for one thing, it doesn't it doesn't match up with those magical ideas of of of being forever young, of of of living your life across the span of centuries, etcetera.

It's more about um narrowly, narrowly avoiding death as long as possible, and there is a there's a fixed term limit there, Yeah, exactly. I mean you could imagine that this is the quantum mechanics version of being tiffanous, right that you essentially and pretty much all universes decline as normally the laws of physics would dictate into a state where you are no longer in good health or whatever.

But things just keep preventing you subjectively from dying, right, and then in that in most universes you would keep dying, you just subjectively would never experience it because you just keep getting funneled more and more into that smaller minority of universes where you go where you go on now. According to Everett biographer Keith Lynch quote, Everett firmly believed

that his many worlds theory guaranteed him immortality. His conscious knows, he argued, is bound at each branching to follow whatever path it does not lead to death. That's interesting, and especially it's strange since Everett died so young. Yeah, yeah, and you know it, it's interesting to come back to done.

I feel like the weirdly enough that's This is exactly the sort of thing that's touched on in Frank Herbert's done, the idea that humanity should take this golden path instead of the path to stagnation, which is chosen by taking the safest route, by always making the safest small choice, instead of figuring out what is the what is the

ideal long term route? Well, does this play into the choice to take Spice in the Dune universe, Because in the Dune universe, Frank Herbert wrote that, you know, one of the main uses of spice, the stuff that's produced by the makers um, is that it prolongs life, right, it is the geriatric spice, that's true. Yeah, But but then it's also you see its use with the Spacing Guild, where the idea is of the space acent could has

their way. You know, they're just gonna always I mean, they navigate space by figuring out how what path avoids every possible catastrophe. And that's it's kind of like the quantum immortality model here, except of space travel. There's a quote to this effect from Laude deep In Frank Herbert Stone quote the vision of time is broad, but when you pass through it, time becomes a narrow door. And always he fought the temptation to choose a clear, safe course,

warning that path leads ever down into stagnation. Well. Yeah, if you look at life as um as sort of you always have to take a risk in order to do something meaningful, right. I mean, there's very rarely a thing you can do that's very powerful and meaningful that doesn't risk at least some small part of your your at least sense of safety. Right. That might just be

psychological safety. But if you you extend that to the extreme, would you become in this quantum multiverse in the many worlds interpretation, and a progressively more boring person because you're always being limited to the options of your life that are always narrowing into this window of worlds where you've taken the safer route, and the versions of you that took the more dangerous route and took risks didn't make

it as far. Yeah, you can only lead to stagnation that way, Like the only way to lead the golden path is that all other paths were platinum, right, which is kind of a depressing way to think about life. But this is a strange thing because it doesn't It doesn't even give you the opportunity. If you were to assume that the mini worlds version of quantum immortality is real, you wouldn't even have a choice in the matter, because

you could take risks. But subjectively, we know that you're not going to do that because the versions of you that did that will eventually disappear and you will have no choice but to be funneled into this the safe, stagnant existence spacing guild winds. Again. Uh so we should

definitely talk about problems and criticisms of this idea. Uh, there are a lot of reasons to think that this might not be the case, so as as we said earlier, But we just want to stress again we are not advocating the idea that you are immortal according to the laws of quantum mechanics. Correct. We cannot be anymore clear on that at that point, and even some of the original authors of this experiment that they've come to doubt it. Like Max teg Mark, the m I T physicists we've

been talking about. He proposed quantum suicide and quantum immortality as thought experiments, but he acknowledges the tenuous nature of the premises under them and actually doubts it could be a reality based on plenty of concerns he has, Like one problem is that tag Mark has these caveats to the quantum suicide experiment and says that it would only even work in theory if the determination of whether the machine kills you is truly quantum, as in depending on

a quantum particle in superposition. It wouldn't necessarily work if you were letting it depend on say a coin flip, could be purely deterministic. Also, the machine must be guaranteed to kill you on the kill setting. It couldn't. It

couldn't have a possibility of just injuring you. Also, it would need to as we mentioned earlier, if it does kill you would have to do so instantly, not gradually, because you can't have the you can't have a chance that it takes you a while to die after the quantum coin toss and uh, and you're just sitting there waiting to find out what happens, because then your consciousness could get routed into that universe. So, just from like a design standpoint, it would it sounds extremely difficult, if

not impossible, to create the right kind of technology. You certainly could make it in your garage. Because it would need to depend on the quantum. It would need to never fail, like it could absolutely. If it could malfunction, that would destroy the whole experiment, right, it at least

should have a very very small chance of malfunctioning. Now, in criticism of the general idea of quantum immortality extending beyond the quantum suicide experiment itself, but just like does this apply to reality as a whole, should we all

expect to subjectively live forever um. Even though tag Mark does seem to subscribe to the many worlds interpretation, teg Mark says that most accidents and cause common causes of death do not satisfy all three of these criteria, and plus there's a bigger problem about tag Mark talks about the fact that most life and death scenarios don't actually break down into a clear life or death binary where you've got continued consciousness on the one hand and non

continued consciousness on the other. But he says, you know, it seems to be that there is a gradual reduction of consciousness as one progresses toward death. And if this is the case, then you could have the assumptions of this violated, right if you can gradually ratchet down your level of consciousness, you know, I mean it's true, I mean we we in fact, I mean I don't sit around fearing the termination of my consciousness. I fear all the things leading up to it and surrounding it, you know,

all the consolation prizes. Yes, certainly, I mean, especially on this view, because if you take the view that there's literally nothing after death, there's nothing to fear there. Yeah, I mean exactly. But that also brings up another big problem is that we don't actually know exactly what happens to consciousness at the time of death. And I'm not saying that you have to propose, you know, religious type answers about souls and afterlife and stuff like that. Obviously

some people believe in things like that. But even if you don't believe in anything uh spiritual, supernatural, anything like that, there's still things that could happen with the subjective phenomena of consciousness other than just it blips out of existence, right, yeah, like you come back as a goat, or or there could be I mean, if consciousness is some kind of process or substance, there's a there's perhaps some some way in which it lingers or winds down slowly after death,

or is reduced to some kind of other, you know, liminal or peripheral state after death. I mean, it's we we just don't really know what happens. There's no evidence about what exactly happens there also, to be honest, we don't actually really know. If we're gonna pick nits, I don't know what it means to survive from one moment to the next as a being experiencing consciousness, except that we all generally tend to be under the impression that this is happening to us. I'm under the impression that

I'm surviving. But if we live in a universe where constantly we're branching off into different branches, you know, out of a quantum superposition and different timelines, how does the baton get past? Does that make any sense? Late? Yeah, I know. I mean this gets down to the basic naval gazing that we've engaged in before. Regarding the present moment? Am I now who I was a minute ago? Am I now who I will be a minute from now?

I mean, when you start really focusing in on that, it starts becoming it starts feeling disjointed, perhaps disjoined, it in a way that could match up with this idea of branching realities. Yeah, how does the now you pass the token of subjective experience to the you of one moment in the future. Yeah, And what happens when the baton has dropped? Right? Yeah? Exactly? So? Uh, And again

I'm not sure that presents a problem. I just say that's something that we're not certain we've really worked out yet, Right, What does it mean? For experience to exist across time, especially if that experience is branching into clones or copies of itself. Yeah yeah. When you start actually lining it up with the human experience, things are a little as certain. It's it's often easier to line it up with created things, like looking at chapters in a book or levels in

a video game. Yeah yeah. So I don't bring that up to say that it like disproves the validity of the quantum suicide or quantum immortality thought experiments, But I just want to suggest that the periphery assumptions underlying these thought experiments are not as simple as and straightforward as they seem. Not even the physics assumptions, but just the assumptions about death and life and consciousness and survival uh

as as even more doubt to throw on here. Max Tegmark himself explains that he later came to doubt the validity validity of his own quantum suicide experiment um, but for totally different reasons. He came to doubt the validity based on doubts about the concept of infinity as applied to physics, which he is in some sense skeptical about. Uh though he admits to being in the minority of physicists on this point. Now, I mentioned video games earlier and uh, and that's because I wanted to talk just

a little bit about saves scumming. What does that mean? So I was familiar with save scumming from playing a fair amount of x COM and XCOM to the most recent incarnations of the x COM video game. I've never played these, so you've got to explain to me. So x Com is basically it's aliens have invaded or are invading, and you have to fight them using a squad of soldiers.

And if you're playing just kind of like the vanilla version of the game, then each time you start playing, you get a random bunch of recruits and they level up as you a and then in each tactical mission you can lose the various men and women in your service, and the ones that survive they level up and get stronger, and you proceed through the game in an attempt to save the world, to outlast the doom counter uh and win the game. Now, the real hardcore fans like to

play um an iron Man version of this. So this is where you have only one save file and no matter what happens on a given mission. You just keep going. You just lost your best guy due to something like freak accident or a terrible shot or a terrible choice on your part. Too bad. You just have to keep playing the game until you either reach the point where you cannot win, whether where the doom counter catches up with you um or you just get to the final

encounter and you're not strong enough to beat it. But you can also do what is called saves coming and this is more in line I think with the way of a lot of people have played video games in the in the past, especially once, where you get to save as often as you want, as many times as you want, and in doing this, you simply go back to a previous save file every time something bad happens.

Oh yeah, okay, so it's kind of yeah, it's kind of like the saving function serves as like a place where you can save the timeline of the world before it branched off into its different many worlds. So it's like, oh, I just lost my best dude by having them look around this corner. I'll go back to a previous save game and I'll have him look around the other corner instead. Yeah, going between the different save files is like getting away to navigate the many worlds from above, and it leads

to a certain kind of quantum immortality. Yeah. I mean, even in a normal game, not like the one you're describing, you can't get to the final boss, say, in a version of the game where you died on the first level, like you you know, and that's all you did. You can't keep going on. You have to use a version where you survived and progress. Yeah, and uh, you know, And of course I don't want to imply that one way is better than the other when you're playing a

video game. My approaches play the video game, however, makes you happy. But you know, Richard K. Morgan also got into this little bit in Altered Carbon because you have these these uh these super rich Methuselah as they call them, the meths who who put their consciousness in different bodies, um, different sleeves as they call them, and you have characters who will end up essentially saves coming with their body. Something happens that either you got them killed or drives

them mad or makes them feel you know, too much guilt. Well, then they just revert to a previous save file. A previous version of their own consciousness, and they keep going. I mean, I wonder if some people, I wonder about psychological effects of video games that could put you in that state of mind without the ability to physically do

what you're describing with the sleeves and the bodies. I mean, is somebody who plays a whole lot of video games with save files conditioning themselves too to act like that is the way the world works, even though it is not the way the world works. Now that that's an interesting question. I mean, we've certainly discussed on the show how things like you know, language is the sequential aspects of language might impact our our experience of reality. So yeah,

why not? Maybe there's a book out there, the Mario and the Goddess, Uh, to get serious. I do think one thing that we should say before the end is I we've taken pains to try to highlight all of the reasons that you can't just trust that the quantum immortality thing is real, that the quantum suicide experiment would

actually work. Um, there are a lot of reasons to doubt it, but we just want to emphasize again for serious reasons that the idea of quantum immortality is highly speculative and relies on a lot of assumptions which could be wrong. Maybe the many worlds interpretation is wrong. Even if the many worlds interpretation is correct, many of the assumptions underlying the experiment and how consciousness and survival and

death and branching works could be wrong. So we should acknowledge that if somebody puts too much confidence in this view of the world, it could actually be dangerous. And I read a tragic story in nineteen whoever It's daughter Elizabeth, actually did commit suicide, and she reportedly left a note saying that she planned to join her father in another universe. I don't know if that means her suicide was motivated

by a belief in many worlds immortality. It might not have been, But in any case, quantum immortality wouldn't work like that. But it seems to me that it's worth clarifying that even though this is an interesting thought experiment, it's by no means a good reason to attempt suicide or to throw caution to the wind and count on many worlds consciousness funneling to save you your Your life is valuable, how it is, pursue it, how it is yeah, and we we'd like to remind you that if you

are troubled by suicidal thoughts, you are not alone. A sympathetic year is only a phone call away. In the United States, consider calling the National Suicide Prevention Hotline at one to seven, three, eight to five five, and visit suicide at Prevention Lifeline dot org for additional resources tailored toward general and specific needs such as those of youth, disaster survivors, Native Americans, veterans, loast survivors, l g B, t Q, and attempt survivors. And you'll also find a

list of international suicide hotlines at suicide dot org. If you're actually thinking about it, get in contact. It matters. All right. That's the episode and we'll be back for more in the future. But in the meantime, you can check out all past episodes of Stuff to Blow Your Mind at stuff to Blow your Mind dot com. You'll also find links out to our various social media accounts. They're huge, thanks as always to our wonderful audio producers

Alex Williams and Tary Harrison. If you would like to get in touch with us directly by email and let us know feedback on this episode, or any other or just to say hig, gain in touch, let us know what you like about the show, maybe suggest to topic for the future. You can email us at blow the Mind at how stuff works dot com for more on this and thousands of other topics. Does it how stuff works dot com the biggest