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brian queen Ann you most recent book until the end of time. You call Bertrand Russell, the debate we had about god in nineteen, forty eight, he says quote so far- scientific evidence goes. The universe has crawl by slow stages to somewhat pitiful result. On this earth is going to crawl by still more pitiful stages. To condition of universal death. If this is to be taken as evidence of purpose, I can only say that the purposes won the day.

Not appeal to me. I see no reason, therefore, to believe in any sort of god as quite depressing statement As you say, this is a bleak outlook on our universe and the emergence of human consciousness. So let me ask what is the more hopeful perspective taken? The story,

I think the more hopeful perspective is to more fully understand what was driving bertrand Russell to this perspective and then to see it within a broader context and really that's in some sense. What what my book until the end of the time is all about, but in brief I would say that there's a lot of truth to it. Bertrand Russell was saying there when you look at the second law of thermodynamics, which is the underlying scientific idea. That's driving this notion that everything is going to wither. Decay fall apart, yet that's true. Second law of thermodynamics establishes that disorder entropy in aggregate is always on the rise, and that is indeed interpreted bull as disintegration, destruction, overs,

the long timescales? But my view is when you recognize how special that makes us that we are these exquisitely ordered configurations of particles that have only will last for a blink of an eye in cosmo logical time. Like terms the fao, there were here, and we can do what we do to me. That's just really something inspires gratitude, and wonder and and a sense of of deep purpose by virtue of being these unique collections of entities that happened to run eyes up, look around and try to figure out where we are and what the heck we do with our time. So it's not that I would disagree with Bertrand Russell in terms of the basic physics and the basic, unfolding by thing, is really a matter of the slant that you take on what it means for us, so maybe we'll skipper on a bed, but

yes, the biggest possible question than you said purpose. So what's the matter of it. All, then, is Is there a meaning to life, though we can take from this? That, from this brief emerges, have come? What city that arises from simple things and then goes into an he death at it? once again return to simple things. As the march of the second law thermodynamics goes on, I think there is, but I dont think its universal answer, and so I think, throughout the ages there has been a key if quest for some fine, oh way of articulating meaning and purpose, whether it's god, whether it's love when there is complete ship a minute. Many people put forward devoid of taken this question on, and there is no one right answer when you recognize deeply that the universe doesn't care. There is nothing out.

arr. That is the final answers not as though we need a more powerful telescope and somehow we can look deeply into the universe. All will become clear in fact, deeper. We ve looked but literally metaphorically, into the eu first hand into the structure of reality. The morgue become clear that we are just a momentary byproduct of law. Was the physics that dont have any emotional content they don't have any intrinsic sense of meaning or purpose. And when you recognise that you realise that searching for the universal for this kind of a question is a fool's errand. Every individual has the capacity to make their own meaning to set their own purpose, and that's not some platitude, thou,

is what we are, because there is no fundamental answer: it's what you make of it and, however much that may sound like a hallmark card. This really is the deep lesson of of physics and signs more generally, over the past few hundred years, where there's some level where you can jack say we say that whatever got going on here is caught a peculiar kind of special. In an interview complexity and may be given begin. To measure it in like come up with metrics, where What I would have gone on earth these like up interesting, hierarchical complexities that form more more sophisticated, illogical system that seems kind of unique. When you look at the entirety, universe, open, the the observable part, though we can see with our tools I mean, so I have to ask, as you describe me,

once again showing her wrote the book, what is life based on a few lectures he gave in that you, forty four. So let me ask the fundamental question here: what is, life. This particular thing we've got going on here. This pocket of complexity that emerged from such simple things get tough question. I asked that question even to Richard dawkins once and I already have my preconceived notion, which he pretty much confirmed, which is, if one could give an answer to that question that allowed. You sort of draw a line in the sand between the not living and the living. Then perhaps we would have the insight that we hear and four and try to say what is so special about life. But the fact of the matter is it's a continuum. A continuum from the things that we would typically call common living inanimate to the things that we obviously call animate and full of the currents of life,

Somewhere in there, it is a question of the complexity of the structure, the ability of the structure to tee in raw material from the environment and process it through a metabolism that allows these structure to extract energy and to release entropy to the wider environment somewhere in those collections of biological processes is the necessity or the nest. Sorry, ingredients and prostitutes for life? But drawing line in the sand is not something that were able to do, but I would agree with you it's deeply peculiar it may in

be unique, but it may not? It could be that the universe is such that under fairly typical conditions, a star, that's a well ordered source of low entropy energy, as with the sun, is together with a planet being bathed by that low entropy energy. Together with a surface, it has enough of the wrong constituents that we recognize your fairly commonplace result of supernova explosions, where star are spews forth the result of the nuclear furnace. That is the core of a star. It could be that all you need are those fairly commonplace conditions and may be. Life naturally forms the james web space. Telescope right has gone up, hopefully

The and one of the one of the goals of that mission is to look at atmospheres, ran distant planet. Some perhaps come to some sense of how special or not life or leave life. As we know, it is in the universe. which part of the story of life a stick to earth for second, do thing is is the hardest if you are like a a betting man which part is the hardest to, it happen. Is it the origin of life again I drawing the line of work, as you say, the line between a rock and rabbit that part is. It are complex organisms like multi sally organisms. Is at the core going out of the ocean where the fish somehow figured out how to crawl around Is it then the asshole sapiens as we like to think of ourselves, ass, special

well an intelligent, or is it somewhere in between? As you also talk about again and very hard to know, at which point this consciousness yeah emerge like if you, if you are to sort of took us, a survey made bets about other earth like planet in the universe. Where do you think they get stuck the most while I would certainly see if we're going to go all the way to conscious beings like ourselves. I would put it at the onset of consciousness, which again I think is a continuum. I don't think it is something that you can do the line in the sand, but there

the obvious circumstances are obvious creatures such as ourselves, where we do recognize a certain kind of self reflective, conscious awareness and if we think about what it would require for a system of living beings to acquire consciousness, I think that's probably the hardest part because look take earth, and recognise that weren't. For you know some singular event. Sixty five million years ago, were this large rock slammed into planet earth and wipes out the dinosaurs, maybe the dinosaurs would still rule the planet and they may well have not developed the kind of conscious awareness that we have so far. billions of years on this planet, there was life that didn't have the kind of conscious awareness that we have.

It was an accidental event in astrophysical history that allowed a mammalian species like us to ultimately be the end product and so yeah I could imagine, is a lot of life out there, but perhaps none of its wondering some meaning of life or trying to make sense of it just going about its business of survival, which of course, is the dominant activity that life on this planet has practised we're a rare exception to that, and I really appreciate that you lean into some of these unanswerable questions from me today, but the so you think about consciousness, not as like a fake shift the binary zero one you think of it continuum that human somehow are may be some of the most conscious beings on earth so serious. So I'm happy

the dispute that yes or no well in hand it's a very hard argument. People imagine that rocks probably will stay quiet on the matter may be not right for the moment there waiting for their opportunity, but but but I I agree that, Look even when you and I look at each other- I am not fully convinced that you're a conscious being right away. I think that you are onto me emma. Your behavior is such that that's it an explanation but what's going on but of course were on the position of all me having direct fairness of her own conscious being and therefore when it comes to other crops you're in the world. We in a similar state of ignorance regarding, what's actually happening inside of their head if they have a head, and so it's hard to know how singular we are, but I would say, based on the best available dead and the best explanations we can make add. There is something special about us. I dont think

that there are fish walkin around and you know coming up with. You know existential ism I know that there are. You know, dogs walkin around who developed and understanding the general theory relativity. They may maybe were wrong, but that seems the best explanation. What do you think is more special intelligence or cautiousness? I think consciousness, and I think that there is a deep connection between these ideas are distinct but they're deeply connected. But look I mean to me and to of course many philosophers actually coined a name for this. The hard problem of conscious that your david chalmers and others as a physicist, I look out the world and I see its particles governed by physical or we can aim that you have got electrons. We got corps, that come in various flavors and so forth. We have a list of ingredients that science has revealed and we have this too laws that seemingly

the govern, those ingredients and, and nowhere in there is even a hint that, when you put those particle together in the right way, an inner world should turn on and is not only that, there's no hint it's insane. I mean it's ridiculous. How could it be that a thoughtless, passionless emotionless particle when group, together with compatriots somehow, can yield something so deeply flawed. And to the nature of the ingredients themselves. So so answering that question I think, is among the deepest most difficult questions that we face, I think it is in fact a really hard problem, or is it possible

you mention new book that is just psycho, almost like a side of fag as an emergent thing, that's like as nice as, like a nice little feature yeah. Well, I mean when people use the phrase hard, problem in they mean, in a somewhat technical sense that it's trying to explain something that seems fundamentally unavailable to third party objective. Analysis right, I'm the only one that can get inside my head and I I tell you a lot about what's happening inside my head. Right now is reflected in what I'm saying, and you can try to deduce things about. What's going on and stop me but you don't have access to it in the way that I do, and so it seems like a fundamentally different kind of problem. From the ones that we have successfully dealt with in the course of centuries and size. Where we look at the motion of the moon, Everybody can look, everybody can measure it. We look at the properties of hydrogen,

when you shine, lasers on everybody, can look at the data and understand it, and so it seems like a fundamentally different. In that sense, it seems like it is hard relative to the others, but I do think ultimately that the explanation will be as you recount. I think that a hundred years from now- or maybe a thousand it's hard to predict the timescale for developments, but I think we'll get to a place where will look back and kind of smile at those folks in the twentieth century and before twenty percent, and before the thought consciousness was so incredibly mysterious when three out of it as a it's just a thing that happens when particles come together. An end, however mysterious that feels right now. I think, for instance, when we start to build conscious systems

things that you are more familiar with, and I am only start to build these artificial systems and an assessment report to us and feeling sad we are anxious. Yeah, there's a world going on inside here. I think the mystery of consciousness will just begin to evaporate, was foresaw beautifully, put, and I agree, Will you completely just the way you said it ill begin to evaporate? I have built the quite a few robots and have had I'm do emotion, emotional type things as media that what you're saying this kind of mischief consciousness starts, evaporate that the

kind of need to truly understand to solve the hard problem of consciousness like disappears because well I don't really care if I understand or can solve the hard problem of consciousness. That thing sure, as heck looks conscious now. I feel like that way. When I interact with a dog, I don't need to solve the problem of cautiousness to to be able to interact, And a richly in enjoy the experience with this other living being icy same thing with other humans are need to fully understand and that there are some aspects Maybe this is a little bit too engineering focused, but there's some aspect in which he feels that consciousness is just the nice trick to help us communicate with each other. It sounds ridiculous to say, but server the ability to experience the world is very you

for in a subject, the sense is very useful, so put yourself in our world and to build described. The experience to others could be just justice social only emerge the animals, this sort if permanent ban was, might experience cautiousness in some more primitive way, but this kind of rich subjective experience that we think about us humans, I think, is probably deeply couple like language and poetry their residence, with my view as well, I mean there's a scientist. Maybe you spoke a term michael graziano from Winston yeah. He am he's developed ideas of consciousness. That look. I don't think they solve on, but I think they do illuminated in an interesting way were basically, we are not aware, all the underlying physical chemical processes that make our brains and our inner worlds, tick, the way they do and because of

dissociation between sensation and the physics of it in the camp, very often the biology of it. It feels like Our minds enter into worlds are just unfettered like floating somewhere in the gray matter inside of our heads and the way I do think that is like look. You know if thumb, if, if, if you were in a dark room right and an eye glow in the dark painter, my fingers. So all you saw my finger dancing around. There is something mysterious how how could those the fingers be doing that and then you turn a light rose. Others disarm underlying it and that's the deep physical connection explains it all and I think that's what we're missing the deep physical connection between what, happening appear and what is responsible for it in a physical, chemical, biological way and so to me, that at least gives me some understanding of why consciousness feel so mysterious, because we are surprised,

sing, all of the underlying science that ultimately is responsible for it and one day we will reveal that more fully. I think that will help us tether this experience to something quite tangible in the world. I wonder if the mystery is an important component of enjoying something so once once, we know how this thing works Maybe we. will no longer enjoy like this conversation will seek other source of enjoyment, but. there's. This is again for managing our perspective. I wonder if the mystery is is an important component. Well yeah this. Have you ever seen, there's this beautiful interview that richard feynman, Did your great nobel laureate physicist responsible for life our understanding of quantum mechanics want to feel the and so forth, and he was in it.

Rotation within interviewer, where he noted that some people feel like once the mystery is gone once science explain something it. The beauty goes away now. You know the wonder if it goes away and he was emphasizing in his. responses, I now that's not the right way of thinking about but when I look at a rose says yeah, I can still deeply enjoy the aroma, the collar the texture is. But what I can do that you and if you're, not a physicist. I can look more deeply and understand where the red cross from where the aroma comes from, where the structure comes from. He says that only augments, my wonder it only augment my experience. It doesn't flatten it or take away from it, so I didn't write, but why should I take that as a bit of a of a motto in some sense that that there is,

is a wonder that comes from a kind of ignorance out mean that in a derogatory sense, but just from not knowing so there is a wonder that comes from mystery is another kind of wonder that comes from knowing and and and and deep knowing, and I think That kind of wonder has its own special character. That, in some ways, can be more gratifying. I hope he is right. I hope you're right and by there's also a movie he he said something vulcan, like sizes and onion, or something that you can peel back. He could argue would keep peeling I mean there is also when you their understand, something there's always a sense that there is more machine to understand You never get to the bottom of the, Yeah mystery birthing is also different. Then you know

begin analogy. I say to a magician rackliff images, him it doesnt, regular nonsense. I, on my god, tat was that's ridiculous when you fight but but nature is perhaps the best magician if you want to try to make the analogy there, because when you peel things back and you understand how it is that things have collar and you have electrons dancing from one orbital to another emitting photons at very particular wavelengths that are described by these beautiful equations of quantum electra dynamics, part of which is fine and develop. It gives you a greater sense of awe when they occur. And his pull back then what happens in other circumstances where it does flattening completely yes very possible. Then saint physics, though we arrive at a theory of everything they unifies the laws of physics

The very strong understanding of the fabric of reality, even like from the votes for the big bang to do today, is possible that that understanding is only going to elevate our appreciation of this whole thing. That figure, will, but they will amity as it has so far, but the other side of it with you, which you emphasizes it's not like science, somehow reaches an end right. There are certain categories of questions that do reach an end. I think we want I will close the book on nature's ingredients in the fundamental laws. Now that we can't prove that may be, it goes on forever. Smaller and smaller, maybe they're deeper and deeper laws, but I I don't think so. I think that there's going to be a collection of ingredients and a collection of basic laws, that chapter will close but

it's one chapter now we take that knowledge and we try to understand how the world builds the structures that it does. You know from planets to people to black holes, to the possibility of their universes and every step of the way. The collection of questions that we don't the answer to only blossoms and so there's there's a deep sense of gratification from understanding certain qualities of the world, but I would say that if you take a ratio of one, We understand to the things that we know that we don't yet understand that ratio keeps getting smaller and smaller does the things that we know that we don't understand, grows larger and larger d ever hoped there We saw that theory of everything puzzle in the next, for decades but a bunch of attempts from string theory to all kinds of attempts at trying to solve quantum gravity, basically come up with a theory for quantum gravity,

there's a lot of complexity, this one for export. the validation you have to observe effects that are very difficult to measure since, build the vatican engineering challenge and then there's the gary challenge, which is like a things very difficult to connect. Tat the laws of gravity to quantum mechanics. Do you have a hope, or we obviously stuck where I have to have to have a hope, a minute in some sense, by devoting these part of my professional life toward trying to make progress on, I'm glad you used the phrase, one gravity, I'm not a great fan of fear of everything phrase because it does make other scientists feel like if they're not, working on this sort of a working mans, like you know, there's not much left you're talking about theory of everything biology is just small details. Can't figure out yeah so so it is really trying to put gravity and quantum mechanics together.

And since I was a college kid, I was deeply fascinated with gravity, and as I learn quantum mechanics, the the notion of physicists banks dumped on trying to blame. Them together. How could one not get fired up about maybe contributing something to that journey, and so we- and on this you I've been on this for thirty years and student. We we have made progress. We do, ideas you mentioned string. Theory is one possible scenario. It's not stuck string. Theory is a vibrant field of research that is making credible progress, but we have not made progress on this issue. experimental verification, validation which, as you know, it is a vital part of the story. So I would have hoped that by now we would have made contact with observation. If you would have interviewed back in the eighties, when I was, you know why

a bright eyed kid trying to make headway working eighteen hours a day and this sort of stuff opposite yet by by twenty twenty one, yeah we're going to know whether it's right or wrong will make contact I would have said look there may be certain mathematical puzzles that we've yet to work out, but we'll know enough to make contact with experiment that has not happened. On the other hand, if you'd event to me back then and asked me, will we able to talk about detail, qualities of black holes and understand them at the the level of detail that we actually, I would have said, no I dont think that we're going to be able to do that. Will we have a an exact formulation, string theory in certain circumstances? No, I don't think we're going to have that, and yet we do so. It's just to say you don't know whether progress is going to happen, but, yes, I do hold out hope that maybe before I move on to,

ever. I don't think there is an after, but I would love before. I leave this earth to to know the answer, but science and the universe. It's not about pleasing heavy hint which bore it is what it is. And so we just press onward and we'll see where it goes. So in terms of string theory, if I just look from an author's perspective currently at the theoretical physics community string theories, the theory was, as a theory has been very popular for or for a few decades, but it is recently fallen out of favor, or at least has been like. You know. It became more popular to kind of ask the question is string theory really the answer: where do you fall on this like? How do you make sense of this puzzle? Why do you think has fallen out of favor? Yes, I do. I would actually challenge the statement. That's fallen out of favor. I would say that any field of research when it's new and it

the bright shiny bicycle that no one has yet seen on that block gets going to attract attention and the news out. You're gonna cover it and students are gonna, flocked to it sure, but as a as a field mitch wars it does shed those qualities because it no longer, as now well as it was when it was first introduced thirty forty years ago, but you need to judge it by a different standard needs to judge it by. Is it Can progress on foundational issues deepening our understanding of the subject and by that measure, string theory is, is: is scoring very high, now, at the same time, we also need to judge whether it made contact with experiment as we discuss before too, and that measure were still challenged. So I would say that many strength, dearest, myself included, are are very sober about the theory.

It has the tremendous progress that it had thirty forty years ago, that hasn't gone away, but we become better equipped at assessing The long journey ahead and that something that we weren't particularly good at back, say in the eighties look when I was starting out in the field. There was a sense of physics is about to end if is about to be the bill, and all final unified theory in that will bring this chapter to a close. Now, I have to say it was more. The younger physicists, who are saying that some of them were seized, and even if they were pro string theory at the time I don't have their rolling their eyes, but they knew that was be a long long journey? I think people like you, know John schwartz, one of the founders of strength, Michael grain, no relation to a founders of the theory, edward witten,

the main people drive and the theory back then, and today I think they knew that we were for a long haul, and and that's that nature of science, quick, kids, that resolve everything few and far between- and so, if you were in for the quick solution to the big questions of the world than you would have been disappointed- and I think there were people- are disappointed and moved on and work on other subjects, if you're in in the way that Einstein was in a lifetime of investigation, to try to see we're. What the answers to these questions would be. Then I think string theory has been a rich source of of material that has kept So many people deeply engaged in moving the frontier forward. There's a few qualities about string theory, which shared weird I mean a lot of physics is weird

beautiful. So we asked the question: what do you as most beautiful by string theory? What what? What attracted me to the theory at the outset, beyond it's putting gravity and quantum mechanics together, which I think is it's true claim to fame, at least on paper. It's able to do that would attract me to theories the fact that it requires extra dimensions of space, and this was an idea that intrigues me in it in a very deep way, even before I really understood what it meant. I somehow had mean talk about sort of the emotional part of consciousness and cognitive part in some, perhaps you strange in some strange emotional way, was enamored with einstein general relativity, the idea of curved space and time. For I really knew what it meant it just spoke to me. I don't know

was to say him and then, when I subsequently learned that people had thought about more dimensions of space than we can see and how those extra dimensions would be vital to a deep understanding of the things that we do see in this world. Four five six dimensions might explain why there are certain forces in part goals and how they behave. To me. This is amazing, utterly amazing, and then, when I learned that string theory, waste. While these ideas embraced the general theory of relativity embrace quantum mechanics embraced the possibility of extra dimensions, then I was then I was hawked, and so when I was a graduate student, we just spend hours, but we, I made a couple of other graduate students for myself who had or have sort of worked really well together at oxford. In england we would we would work, these enormous numbers hours a day, trying to understand the shapes of these extra dimensions, the geometry of them. What those geometrical

shapes for the extra dimensions would imply for things that we see in the world around us and it was a it was a hettie hettie time and and that kind of excitement has sort of filter through over the decades. But I'd say that's really the the part of the theory that I think really hooked me most strongly How are we supposed to think about those extra dimensions? I was supposed to imagine actual physical reality or or is this morning, there's a mathematics Maddox that allows you to serve come up with tricks to describe the fundamental reality that we move more directly perceive no one really knows the answer of course. But if I take the most straightforward approaches, drink theory, you really are imagining that these dimensions. Are there they're real, I'm in just as you would say that the three space dimensions around us no left right back? Fourth, uptown

yet we the real they're. Here we are immersed within those dimensions. These other dimensions are as real as these, with the one difference in their shape in their size, differs from the shape and size of the dimensions that we have direct access to through through human experience, and one approach imagines that these extra dimensions are tightly coiled up, curled up crushed together. If you will into beautiful geometrical form- that's all around us, but just too small for us to detect with our eyes too small. For us to detect, even with the most powerful

and that we have. Nevertheless, according to the mathematics, the size and the shape of those extra dimensions leaves an imprint in the world that we do have access to. So one of the ways that we have hoped yet to achieve to make contact with experiment of physics is to see a signature of those extra dimensions in places like the large hadron collider in Geneva, switzerland and It hasn't happened yet doesn't mean it won't happen, but that would be a stunning moment in the history of the species, if data that we acquired in these dimensions gives us kind of incontrovertible evidence that the dimensions are not the only dimensions me how mine blowing would would that be so, though, Our children, collider you'll, be something in the moment of the particles or also additional ways potentially be a place where you can detect size

for dimensions like was a lie, go but much more accurate in principle. All of these can work. So one of the experiments that we had high hopes for, but at by high of some actually exaggerating one of the experiments that we imagined might, in the best of all circumstances, yield some

In fact, we weren't with bated breath waiting for the result. We knew it was a long shot when you slammed protons together at very high speed of the large hadron collider. If there are these extra dimensions and if they have the right form and that's a hypothesis that may not be correct, but when the protons collide, they can create debris, energetic debris that can in some sense leave our dimensions and insert itself into the other dimensions and the way you'd recognize that is there'd, be more energy before the collision. Then after the collision, because the debris would have taken energy away from the place where our detectors can detect it. So that's that's one real concrete way that you could find evidence for extra dimensions. But yet since extra dimensions of space- and

gravity is something that exists within in fact, is associated with the shape of space. Gravitational waves in principle can provide a kind of you know: tat scan of of the extra dimensions. If you had sufficient control over those processes, we dont yap or perhaps one day we will does it make. You said a little bit looking out into the future. You mention at wooden no no more prizes have been given yet related to string theory. Do you think there will be? Do you think you have to have experimental validation or can about prize be given jouncing is have been given for a long time for purely sort of theoretical contribution here it certainly as a matter of historical precedent, has been the case that those who win the prize have

established investigated illuminated a demonstrably real quality of the world, so gravitational waves. The prize was awarded after they were detected, not not the mathematics of it, but the actual detection of the hague, particle ills that idea that came from the nineteen sixties, Peter higgs and others in fact, and wasn't until twenty twelve on July. Fourth, when the announcement came that this protocol have been detected, the large hadron collider that people You did as eligible for the nobel prize. The idea was there, the math was there, but you needed to confirm. Indeed the prize ultimately was awarded time, not surprised. In fact, I would have been surprised if a noble,

prize had been awarded in the arena of string theory, because it's far too speculative right now is far too hypothetical. In fact, I am simply that it to the view that it really shouldn't be called string. Theory. It degrades the word theory because theory in signs of course means the best available explanation for the things that we serve in the world. The things that we measure in experiments about the world and string theory does not do that at least not yet really should be the string policies right, we're at an earlier stage of development and that's not the kind of thing that noble prices should be awarded for What do you think about the critics out? There appeared a wide he's from colombia to think sabine. Have his daughter.

is that a healthy thing, or should we sort of focus on serve the optimism of of these hypotheses yeah? It's actually a good way that you frame it because I'm always somewhat repelled by views of the world that start from the negative. Try to cut down in idea trotted said: that's the wrong way of thinking about things and so on. I am much more draw maybe because I am an optimist on a much more drawn to those who go out into the world with new ideas, said and done. Try to cut down one Dear, but rather presented another one that might be better

so you make the first idea may be strictly irrelevant because you ve come up with the better approach to the world. So do I think it's healthy? Look, I think, having a wide range of views and perspectives is generally a healthy thing. I think it's good to have arguments within a subject in order that you stay fred. And you stay focused on the things that matter, but in the end of the day I think it's a more vital contribution to give us something new rather than to criticise something? That's their yeah, I'm totally with you, but it could be the nature being an optimist that day and also just the. a low of engineering, is theirs, it helps nobody by criticising the the rock at that. Somebody else built just build a get, bigger, cheaper, better rocket

and this is to be how human cells, as can progress effectively. We we mention the second laughter when I never forget ask about time, and do you think of time is emergent or fundamental per hour, of course I like to think of it as emergent. I don't have a solid reason For that perspective, I have a lot of hints of reasons that some which come out of string theory in quantum gravity that perhaps be worth talking about. But what I would say is time is the most familiar quality of experience, because there's nothing that takes place that doesn't take place within an interval of time. yet at the same time, it is perhaps the most mysterious quality of the world's hurts a wonderful confluence of the firm.

Here and the deeply mysterious all in one little package. If you were to ask me what is time I don't really know, I don't think anybody does I. I can say what time gives us now's is the language for talking about change, allows us to envision the events of the universe being spread out in this temporal timeline and in that way allows you to see the path since that unfold within time. I mean time, allows us the structure and the organization to think about things in that kind of a progression. But what action is it. I don't really know- and that's so strange because we can measure it right. I mean there are laws

api tories in the world that measured this thing called time to spectacular precision. But you know, if you go up to the folks and say like what is it that you're actually measuring, I don't know that they can really articulate The kind of answer that you would expect from those who are engineering, a device that can measure something called time to that level. Precision. So it's a very curious combination. What do you make of the one way feeling of causality? I guess causality a thing. Where's that to just a human story that we put on top of this emergency number of time. I don't know My can give you my my guess, my intuition about it. I do think that at the macro skopje level, if we're talking about sort of the human experience a time, I do think it. The macro skype

level. There is a fundamental notion of causality that does emerge, from a starting point that may not have causality built in so I certainly would allow that at the deepest description, of reality when we finally have them on the table. We may not see causality directly at that fundamental level, but I do believe that we will understand had a go for that fundamental level too. a world where, at the macroscopic level there is the notion of a causes, be a notion that einstein deeply embraced in a special theory of relativity where he showed the time as qualities that we wouldn't expect based on experience you and I, if we move relative to each other clocks, tick off time at different rates are clock. it is just a means of measuring this thing called time. So this is really time that we're talking about time, for you and time for me are different if we're in relative mode.

Can he then shows in the general theory of relativity that if we are experiencing different gravity, different gravitational fields are actually more precisely different. Gravitational, angels time will elapse, rush at different rates. These are things that are astoundingly strange, that give rise to a scientific notion of time travel case. This is this is how far einstein took us. And wiping away the old understanding of time and injecting a new understanding of its quality, so said, there's so much about time counter intuitive, but I do not think there were ever to wipe away causality at the mike macro skies The the microscope mean there's so many interesting things at the macroscopic glow. They may only exists the max. Well, yes, like we do. We always talk about consciousness, that that very well could be one of u s, time travel so mean, according to einstein, any

in general, what types of travelled you think are physically universe allows but certainly allows time travel to the teacher, and I'm not talking about the silly thing that you and I are now going to the future sec muslim. A second I'm talking about really the the version that you see in hollywood in terms of its net effect, whereby an end visual can follow einstein in strategy and propelled themselves into the future in some sense more quickly? So if, if I wanted see what's happening on planet earth, one million years from now einstein toes me how to get one million years. build a ship, I gotta turn to guys who know how to build stuff. I can't do it like you building if they can go out into the universe near the speed of light and turn him

and come back. Let's say it's a six month journey and a six month journey back and einstein tells me how fast I need to travel. How close to the speed of light. I need to go so that when I step out of my ship It will now be one million years into the future on planet earth, and this is not a controversy statement read. This is not something weathers differences of opinion in the scientific. Amid a scientist who knows anything about what einstein taught us agrees with what I just said: it's it's commonplaces, bread and butter physics, and so that kind of travel to the future is absolutely allowed by the laws of physics there veneering challenges their third technological challenge close to the speed of, and there are there even biological challenges right. There g forces that you're gonna to

and to you know so, there's all sorts of stuff embedded in this, but those I will call the details and those details notwithstanding the universe allows this kind of travel to the future and if I could pause real quick, he could also, at the macro level, with biology, extend the human lifespan to do a crime of travel forward in time. If you expand how long we live yet, that's away too from a perspective of an observer, conscious, However, that is a human being, your best actually travelling for in time by allowing her to live long enough to see the thing? Yes, citizens, basic biology about travelling back and yeah, that's the m that is the natural next. Especially if you are you're doing you're going on

journeys. Is that a one, my journey, you come back and veto physics committee doesn't speak with a unified voice on this as yet, but I would say that the dominant perspective, as yet you cannot get back now. Having said that, there are proposals that serious people have written papers on regarding hypothetical ways in which you could travel to the past, and we ve seen some of these again hollywood loves to take their most sexy ideas of physics and build narratives around them. This, idea of a wormhole jody fostering contact went to a wormhole deep, space nine times, I'm there. Many other examples where these ideas that have probably never even seen, but with wormholes. There is at least a proposal of how you could take a wormhole tunnel through space time

in April, at the opening of the wormhole in such a way that the openings are no longer synchronous, they are out of sync relative to each which would mean ones ahead in one's behind, which means go through one direction. You travel to the future. If you go back, you travel to the past. Now we don't. There are wormholes the worker and I think they are possible accorded einstein, but even einstein was very quick to say just because my math allows for I think it might also mean it's real him. He famously didn't even believe in black holes. Yeah didn't believe in the big bang right and yet the big, the the black hole who issue is really been settled now we have radio telescopic photographs of the I call on m. Eighty seven was in newspapers are on the world just a couple of years ago, so such as to say that because it's in einstein's math it doesn't mean it's real, but yes, it is the case that wormholes

our allowed by einstein's equations and in principle you can imagine you're putting electric charges on the opening of the warm all allow me to touch them around in a manner that could yield this temporal asymmetry between them. tat, one of the mouse to the edge of a black hole in principle. You can do this slowing down the passage of time near that black all men. When you bring it back, it will be well out of sync. the other opening and therefore could be a significant temporal guy between one and the other. But people study this in more detail question. Could you ever keep wormhole open? Assuming it does exist? Could you ever travel through a wormhole, Would there be a requirement to some kind of exotic matter to profit open that perhaps doesn't exist.

There are many many issues that people have raised and I would say that the general sentiment is. It is unlikely that this kind of scenario is going to survive, are deeper understood. of physics when we finally have a, but that doesn't mean that the doors clothes, so maybe it's a small possibility that this good one davy recitation way to put it it will not. This kind of scenario will not survive deep understanding of physics. It's an interesting where to put it because we wonder what kind of scenarios will be created by our deeper understanding of physics may be sorry to go crazy for a second, but if you have like the pants, I got an idea that cautiousness per it's all matter, maybe traveling in that, whatever laws of physics, the cautiousness operates under some like that? In that view of the universe, we somehow are able to understand that part. Maybe

traveling is so breezy yeah. Although it does not follow the constraints of the speed of light some slight this year. So look I've I've a definite degree of some sympathy with the possibility that consciousness might be more then. What we described earlier is just a by product of my and was particle. You just made the rock happy the hague exactly you know so so it isn't. The approach that feels to me the most likely, but I I see the logic if you ve got puzzle had a mindless particles build mind, one resolution might be, the particles are not mindless. The particles have some kind of protein conscious quality. So there's there's something appealing about that. Straightforward solution to the puzzle, and if that's the case, if we do live in a pan, cyclist, world,

where there is a degree of consciousness residing in everything in the world around us, then, yes, I do think some interesting possum. Billy's might emerge where maybe there's a war if communing with physical reality in it in a deep way than we have so far. I mean we as human beings. A vital part of our existence is human to human communication contact. We live in social groups and that's what it's allowed us to get to the place. we ve gotten. Imagine that we have long missed that. There's other cautious his out there and some kind of relationship or communion with that larger conscious possibility would take us to a different place now. Do I do I buy into this yet don't I don't see any evidence for it, but to have an open mind and allow for the possibility in the future yeah I do so. That's not the case any of these. Some

for particles that at the macro level emerges some interesting stuff like cautiousness? Another thing you read about in the until the end of time book is the thing that assumes there emerged at the macro level is the feeling like here, though, There is a free. Well, I could decide to do stuff, and you have a really interesting take here, which is. no there's not a free will. Allow me to speak for you and your correct me. No there's not a free will. There is an experience of freedom jack. I really love, so where does the experience? Where does freely come from if we don't have any kind of physics based freeware gear and anne said. The idea follows naturally from all that we have been talking about. Let's make the assumption that

at all, there is in the physical universe- is stuff governed by laws we may not have those laws may may not know what the fundamental stuff is yet, but everything we know in science points in the direction that its physical stuff governed by universal laws, and that being the case or that being the assumption, then you come to a particular collection of those ingredients, call the human being and that human being has particles at our. molly governed by physical law and when you then recognise it, every thought that we have every action that we undertake is just the motion of particles when I'm thinking thoughts right now, of course, at this level of description it As the motion of particles cascading down various neurons inside my head, and so on and every site, One of those motions, collectively and individually is fully governed by these laws that

perhaps don't have yet, but we imagine one day we will. That leaves no. opportunity for any kind of freedom to break free from the constraint of physical law, and that is the end of the story said the traditional, intuitive notion of free will that, where the ultimate authors of our actions that we were the buck stops at, there is no anti seed, and that is the cause for our decided to go left or right. Choose vanilla or chocolate live or die that intuitive sensation does not have a basis and are under in the physical world, so that's the end of the free will of the traditional sort. But then your question is what about this other kind of freedom? I talk about and the other kind of freedom. If you focus on it intently, I think, is actually the true version of freedom that we feel, and that freedom is this. You look at inanimate objects in the world, rocks bottles

Water but other they have a very limited, behavioral repertoire. Why they're into organization is too course for them to do very much right. You have to Try to have a conversation with a glass of water. You send sound waves. It doesn't do much may vibrate a little bit, but the repertoire of responses are incredibly limited. The differ between us and Iraq or a bottle of water is that our inner organization, by virtue of eons of evolution by natural selection, is so refined, so spectacularly ordered that we have a huge repertoire of behaviors that are finally a tune to stimuli from the external world. You asked me a question as a stimulus and all of a sudden. These particle process is going to action, and this is the result. The sand that I am giving you so the freedom that we have is not from the control of physical law, the freedom that we have as from

constrain behaviour that is long since govern inanimate objects. We are liberated from the limit behavioral repertoire of rocks and bottles of water to have this broad spectrum of responses. Do we pick them? We do not Do we freely choose them? We do not, but yet we have them and we can marvel at those behaviors and that's the freedom that we have the com laxity in the breadth of their repertoire is is where the freedom carriages Something to be said about emergence a few No, I've looked at much about objects that I Do I love when more than anyone else, which is seller, atop gap like game of life, tat stuff?

Is there a you know from simple things, emerges beautiful complexities, and so that that repertoire is like it seems. If you have enough stuff, just beautiful complexity emerges that sure, as heck tours eyes, looks like there's cautiousness there. There's three worlders little objects in about and making decisions. I mean all of that. You could say it's aunt from a physician, but it sure heck feels like their organisms, making decisions would it what is that emerges thing is that that, within the realm of physics to understand, is it? Is it within the round of poetry. What what is that? like systems, emergencies the? What is that with that?

it'd be understood by science. So here's here's the way that I think about it. So there are clearly qualities of the world that emerge on macroscopic scale. Our sense of beauty wonder consciousness. All these kinds of qualities do I feel that they ultimately are explainable from the laws of physics I do there is nothing that is not alterable and ultimately explainable, with the laws of physics from this physical, his perspective, which is what I take. So you got the particles, you've got the laws and you have things that emerge from the choreographed motions of those particles.

But is that the best language for talking about these emergent qualities? Usually not if I was to take something even more mundane like a baseball flying through the air? If I was to describe it in terms of the courts and the electrons I'd give you this mountain of data with you know, tend to the. when he ate particles and all of their coordinates in spaces of unction atomic and this man a dead. We like, I don't know what this is and then, if you really the clever and lucky. Oh, it's a baseball just described in the in the least economical way possible. It is much more useful and insightful to talk about the baseball flying through the air. Similarly, there are things at the macroscopic level, like human experience and human emotion and human action and the sensation of free will that we under

I hardly all have, even if it itself doesn't have a basis in our understanding, the physical world, its useful to talk about things in this very human language, and so yes, it's vital to talk about things in the poetic language of human experience, but do not lose sight of the fact and some, we'll do they say it's just an emergent phenomena. Dont lose sight of the fact that emergent phenomena are emerging from this deeper understanding that comes from the reductionist, account of physical law and there's a lot of insight to come from that, such as the freedom that used that you had the freedom of will that you thought you had. It doesn't have a basis in that reductions to counsel it's not real speed, the poetry of human experience. You mention the images of the black holes. How to make you feel fear you go in there. First image came up truly amazing. a sense of I guess the feeling was both a mate.

In the end, and there is a little sense of em. Jealousy is not quite the right word, but a sense of longing yeah. I think that's a better word, because here's a subject that started with einstein back in Nineteen fifteen rights down the equations of the general theory of relativity and there there. scores of individuals over the decades, starting with people like Carl swarth child who analyze equations, see the possibility of black holes. People too, These ideas, John wheeler, all these great a visit, it still a hypothetical subject. It gets closer to reality through observations of the centre of our guy. see stars whipping around in a manner that could only really be explained by their being a.

Black hole in the center of our galaxy, but it was still indirect tax. You have a direct image that you can look at what a beautiful arc narrative arc from the theoretical to the absolutely established and that's what we hope will happen with other. is France, the string theory right? I mean wholly mathematical subject at the outset and still pretty much a wholly mathematical subject today yeah, do we long for that image We can look at and say string I mean how thrilling drilling to be part of that journey. To be part of that, that step that move things from the abstract to the concrete. Yeah said like the image at the end of the early images of dna, for example, but there is something especially so. The problem with strings is they're tiny, so it's harder to take a picture a in in in the following sense,

Think of a black hole he ever swirl of. I guess what is even though it does to go wherever light occurring to the event horizon and then there's darkness yet centre and you d, just a man, so that picture in particular. I guess if it is of a gigantic who put a cop you just I mean- is that how you finally billy's at times and ass, the sun yeah says, is both excited. And terrify amino where you the especially, I think it's exciting it first like the longer I think about it. Every time I think about it, the more terrifying it becomes, so it all starts exciting and then a ghost terrifying. Both our feelings were here feelings there. I appreciate it take terrified. Ah you, how is still beautiful? I think I can assure that their reaction, because there is a way in which when work on the subjects like all the time. I teach

I teach about black holes right the equations on the blackboard. The ideas reside in a very cognitive. I don't know mathematical portion of brain or at least for me, and it's only when you like sit down and it's quiet, you start to contemplate way, will really. This is just like a mathematical game. There, these monsters out there now not net and in a sense of I fear for my life, but it's a sense of how extraordinary is this universe, and so it is birthday our, how powerful nature house yet house how stupendously powerful nature is So there is a deep sense of humility that I think this instills

if you really allow the idea to sink in while I have to ask about the most stupendously, powerful, thing to have ever happen in our universe, which is the big bang. What's up with you bank. At the weekend I mean that would gravitational waves. The hope is, you have more, more accurate measurements of the gravitational waves. You can call back further further back in time towards a big bang do give hope to be to understand the the earliest part. They created our universe now that and the deep interior of a black hole I think the biggest mysteries are we hope the melting of quantum mechanics and gravity will reveal illuminated and yeah. What question could be more or captivating. Then why is there something

other than nothing right. Why is there a universe at all and will the theory that were developing, take us to an answered I don't know, even if we truly new at the big bang, is that's a big question his own right when we'd still be left the question? Well, ok, so you explain the process. by which a tiny nugget of our universe, a kind negative space time can undergo some kind of growth to you, the world around does, but presumably in that explanation, you're, gonna, bob mathematics and some ingredients like quantum fields or matter or energy or something where did that stuff come from. You know it. Can we get to that level explanation I dont know if it is remarkable that if you ask what happened the millionth of a second after the big bang

it's not really that controversial and hunger right even though there is a lot of argument in the field at its very heated right now, I should say regarding what is the right theory of the big bang. What is the right theory of early universe, cosmology, where I mean early much early them and of a second a lot of dissent. Alot of heated arguments about that no upon intended, yet right again but but you go like a millionth of a second after that an end were pretty firm grew. is not amazing. Right to two under and you know what happened from that point forward but to go back is- is is controversial. So there is this theory called inflationary cosmology, which I would say has been the dominant power dime sense of early nineteen eighties. So what does that mean? forty years now it's been the dominant cosmo logical paradigm, and it makes you

however curious feature. Weinstein's general theory of relativity his here of gravity. Rhinestones shows us mathematically. Gravity can not only be attractive. You know the kind of gravity that we're used to things pulled together, but it can also be repulsive, and that fact is then leveraged by people like alan guth and and andrea Linda and at the time Paul Steiner. at an android, albrecht and others to say. Okay, we had little nugget in the early universe, which was filled with the stuff that yields this repulsive gravity Well, that would have blown everything apart it because everything to swell beautiful explanation for the bang in the big bang was, and then people mathematically analyze the consequences of this idea and they make predictions for tiny temperature differences across the night sky. Principle could be measured. You send it balloons. You sent up satellites with very refer

and the monitors and they measured the temperature of the night sky and the statistical distribution of the temperature. differences agrees with mathematical predictions. I mean the maze you just We have to stand in awe of this insight, so you think a hot the theory has been established, but scientists are incredibly sceptical, bunch And some scientists, including one of the people who helped developed the theory at the outset, Paul Steinhardt and comes along and says well yeah. It's done this theories done pretty well so far, but there are aspects of this ray that are making me lose confidence. For instance, this theory seems to suggest, that there might be other universes like had. He makes sense of a theory that suggests or other universes. Or are there others you come along and say this theory seems to talk about late skills that are minuscule even by the so called plank length. This

sort of shortest length that we can imagine making sense of in theory of quantum gravity had he makes sense of that and so so they develop a list of of things that they consider to be chinks in the inflationary, cosmo, logical theories, former and they develop other ideas which they claim yield the same predictions as inflation because miles with his temperature differences across space, but dont suffer from these problems and then the imf generic cosmology folks even out or no hang on. Your theories suffers from different problems, and so the arguments gus it it's a healthy debate, talk about real debates and science Sonia ask what's up with the big bang, I don't know right now, If you were to ask me five years ago, maybe even less than three or four years ago said: look inflation, cosmology hasn't issues, but the package of explanations it provides is so potent and the issues.

That beset? It are seemingly solvable to me that Imagine it's going to in the end went out. I would still say that today, but I wouldn't say it as loudly. I wouldn't say it has confidently. I think it's worth thinking about alternate ideas, and it could be the case that the paradigm Some point shifts: does the dark matter and dark energy fit into the the shifting of the explanations for those? Yes, certainly so so dark energy has. in in the inflationary theory is kind of a big mystery. So dark energy is The observation all realisation in the last twenty years that now always universe, expanding its expanding ever more quickly? Something is still pushing things outward, and the explanation is that there is like a residual version of the repulsive gravity,

from the early universe. But it's such a strange number when you write that amount of dark energy using the relevant units in a of quantum gravity. It's a decimal point. far by like a hundred and twenty zero and one were not used to those kinds of numbers. In physics raised to a half one, I e where did to those are the kinds of fundamental numbers that emerge in our explanations of the world, and we look at this bizarre number.

decimal point all the zeros in a one. We say something's wrong there like. Where would that number have come from? And now there are people who suggest resolution to it. So it's not like we're totally in the dark on it, but those people like Paul Steinhardt, who have alternate cosmological theories, cyclic cosmologies as they call it claim that they have a more natural explanation of the dark energy that it naturally feeds into a cyclical process that is their cosmological paradigm. So yeah if the cosmology should change its conceivable. Our view of dark energy may change from deeply mysterious too deeply integrated into a different paradigm. That is possible. I think it's roger penrose that think that Measured complete through found before the big bang, too The big bang yeah is that is the big bang like a full array, you're the hard drive or is there some information that could bleed through yeah? I mean so, sir Roger

is among the most creative thinkers of the last hundred years, rightly won the nobel prize for his insight its into singularity in space time that we know to afflict our mathematical solutions of black holes in the big bang. Soforth agenda He has an enormously fertile imagination and and I mean that in the most positive sense, and so he has put forward this idea, this conformal cyclic, cosmology I think, as the the official title of I could be getting that wrong. I can't say that I've studied it. I have seen lectures on it. I don't find it convincing as yet it feels like it's being. a built to find a solution, as opposed to sort of more naturally emerging? Maybe roger would say

the wise and I don't mean to in any way cast aspersions on the work at its vital. An interesting and people are thinking about it. I dont consider it as close a competitor to say the inflationary theory as, for instance, the stuff that Paul steinhart has put forward. But again you ve got you gotta, keep an open mind on this in this business. When there's so much that we don't. You understand his while to think that information could survive up like that. Just like it is wild, Imagine that information could escape a black hole, for example, it just seems like that. By construction, these things are supposed to not bleed out anything one of the challenges and all these theories is when we talk about a singularity, has Israel sexy term. The singularity but the singularity is is in more ordinary language occurred a physical system where the mathematics breaks down

nonsensical it's like taking one divided by zero. You put that into a calculator, and it says e error right. It does not make sense, doesn't compute and so it's very hard to make definitive events about things like the big bang or about black holes until we cure Mathematical singularity is an some who claim that in certain regimes the singular areas have been cured, I don't buy enemy and think that there is consensus on these ideas. So when one talks about information sort of bleeding through the big bang, you ve really got it I am sure that the equations have no singularity targets. Sickly cosmo, you gotta make sure that the equations done many singularity that you go from say one cycles and the next now. Some of their proponents of these theories claimed that they have resolve these issues. I dont think that there is a general sense that that is the case as yet, but it could be that look. I life is so short tat

I haven't had time to deeply delve into all the mathematical intricacies of all the ideas that have been put forward. That did it never do anything else, but that that's what the issue is, of course, is just math. There may be holes there may be they may be guessed Our understanding in the way were modeling physical. That's the point, in fact, in fact, wendy serves about a job then say modeling, but you got there first and it's exactly the right point, you're at the universe here right now how do you? How do you talk about the universe with a straight face? Mathematics in the way you do. Is you you simplify you, throw away those characteristics of the universe that you don't think are vital to a full understanding, and so we're going to get to a point. People are starting to where we've got to go beyond those simplifications.

so cosmology, has for a long time model the universe in the most simplest terms, homogeneous icy tropic. It has just a few parameters that describe it: the average density of mass in energy and so forth. We have to go beyond the simplification and that will require put these things on computers. We're not can be up to do calculations there so much as asked her fist. ics, has gone beyond many simplification to now, give really detailed simulations of star systems and galaxies of worth we're going to have to do that with cosmology and people are starting to do that. Today, yeah I've seen work on simulation, most simulation measured by the largest awesome, but just like simulation of the early formation of our solar system stand other, like or cloud and just an era that the whole of it to the how earth came to be. They cowed jupiter urged

the protects us protects us there's like weird, like moons and volcano? thousand modeling. All of that, the formation of all that is fascinating, because that Naturally, the question of how this life emerge and these kinds of rocks had arrived become a rabbit bud speaking of models. There's an equation called the drake equation. Talking about life have to ask when at the highest level? First, when you look out there, How many alien civilizations do think out there lewis, zero, one or many so If you say civilization, I would remain. number way down. It could be zero. If you talk about life, I think it could be many

As you say before, I think the move from life to consciousness the kinds of beings that would build what we would recognise as a civilization That may be extraordinarily rare. I hope it's not. You know as a kid I love star trek. I I just love the idea that we will be part of some universal community where look. Experience in planner suggests. It doesn't always go so well when groups who are separated, try to come together and and live in some larger collective, but again as an optimist how amazing would it be to converse with an alien civilization in and learn what they ve figured out about physics in cosmology and and compare notes and and learn from each other and in some some wonderful way, I I love But if you ask me the likelihood of it, I would on saying it may be

oh improbable, that the conditions conspire. to allow life to move to this place of of consciousness at a might be rare. In my view, over simplified things, but just observing the power of the evolutionary process. I to believe, If guy you read and theories of how we went ah ha ha sapiens, evolved it seems like those you process, naturally leads to tears. will they be answers or creatures like that? much better than that. to me as several scary scenarios, so ok, positive scenario. Is life itself is really difficult, so that work of life is difficult. What does fighting for many reasons, because we may be able to

prove that wrong easily in the near term, by finding life elsewhere, the sky, You think he is life is easy. and there's plenty of cautious, intelligent, civilizations out there and we have not They made contact, which means, With intelligence and cautiousness comes this possibility and too destruction so with power comes great responsible and though we end up destroying ourselves. That's the sky. Areas. The positive, I guess version is that may you are being watched, serve like does a transition to where you don't want to ruin the premise villages out there, and so there's a protective layer around us. yeah, they're they're watching so where

where do you in these possible explanation to the fermi paradox? Why haven't we can't? I realize tat you land on? Well, I think the most straightforward explanation is that there aren't any Now there are many other explanation to say you can't be dogmatic about things that are just got feel, but you know one of my favorite twilight zone. Episodes of risk is one where is alien civilization. Finally comes the planet earth in and gives us this book that they really want is too to have until all that in this foreign language. They cryptography they desperately trying to decipher it as humans are going to visit. this other alien plan, and there are many back postcard that wonderful, it is worth and they they. Finally, the decipher the title is to serve man and everyone. So we held other here to service at all, makes sense, and then just as the one of the final crypt,

governs is gone onto the alien ship. His his helper runs and says I've deciphered the rest of the book to serve man. It's a cookbook unesco, Yeah is that is that is possibilities europe, you know, and and so could they be watching us and just waiting for us to get to a mature enough level. I don't what strikes me well, you know, I think, it'd be better to have this conversation after the james webb telescope. I mean I do think that if we look at the atmospheres of many planets mean there's now an estimate now that there's an order one planet per star on average so long. Now that you know the galaxy hundreds of billions of stars numbers of gallia, hundreds of billions of galaxies that we're talking about hundreds of billions of hundreds of billions of planets. How might you know, and if we start to survey some of these.

adds and one after the other half the other? We just sort of fine, no evidence for any of the biological markers it could be. Of course, maybe life takes up. A radically different form is be hard to know that, but I think you know that at least give us some insight on the life question, but I just don't see how we get in on the civilization are consciousness question without yet the direct connection, And- and it strikes me that, if consciousness is ubiquitous, save life is unwilling to grant that if consciousness is also ubiquitous, then I don't understand why they haven't been here. A wider hasn't been subsume because, presumably they should be which further ahead of us, how? Unlike could it be that we're like of all consciousness in a universe where the most advanced that be such a special place for human beings had it's hard for me to grant. That is likely

possibility. Rather, I think kind of run of the mill and there are many who are far more advanced than us and I don't think that they would. spend the energy to hide themselves. So, care enough in so as you see, that's actually what I believe There is very low, number civilizations that are far more advanced than us, but my senses, the he was there, exceptionally limited both in our direct sensory capabilities and our physics are tools of of sensing. cycle the string theory, the multiple dimensions were just not like it's like, I honestly believe that could be stuffed in front of our knows. There were just not seeing workers were too dumb to too much hubris. And he s a bunch of stuff into ignorant as the but to the fabric reality all of those things. We were young epithet yeah into

of intelligence that I guess I say is like I'm on board with all that is real possibility. But then it does strike me that, We are sufficiently able to observe the Look. We can look back to you know a fraction of the duration from here to there. Just a fraction is left that we are unable to sin so how ever young we are. We have been able to sort of pierce the universe, and it strikes me that there would be some signature, but maybe maybe that that's coming, but but the gluck. Having said that, I do look. I I I certainly note the fact that its rare that I stooped down while walking in manhattan and so to dig up some ants in the bushes on the side of the street and talk to the ants I didn't because it's just not interesting to me we're like the ants on the cause. Ballade, you go landscape thing.

I can imagine that the super advanced aliens will be like like who would ever you know, but, but I feel like we're sufficiently advanced that there should be some signal. Signature of that, but maybe it's coming. I think the deeper fundamental problem between us and the answers that would have in language start. That interest is that we don't even have a common language and so the day alien. civilizations, don't even nautical like we, humans have convinced us, or our special because without the language you ve talked about, you talk about the importance of language to intelligence, but makes you wonder like how very is that fat like club, the with like try We created of language and linguistic temper systems that are very specific to kinds of brains, and we share ideas together. Also excited. I can understand the universe cause. We came up with some notation yeah, a math. I wonder, there's some toy

the kinds of language it communicates on a different timescale, with different, very different mechanisms in the space of information that justice, not for everything, everything is lost in translation yet, and it could well be look at him. I think part of the reason I go towards the possibility of the soul intelligence is. This is certain romantic appeal to look out in the cosmos and it's just quiet and it's just eternal silence there, some there's something that appeals to me at an emotional level, that way, but yeah I mean nobody nobody knows it. Certainly it conceivable that where this a radical mismatch between the kinds of things that we are able to observe incentive to versus the kinds of structures that permits the universe, in a manner that simply were unable to defend

while we are alone, This exciting, in one of the ways is exciting- is some that is up to us to become to expand out into the universe to permeate cautiousness out into the universe, says for space aspiration comes here. Let me ask you as a somebody with a string theory, the physicists: do you think space exploration colonizing space? The visit, or an engineering problem. What would you say, yeah having is fundamentally in engineering problem if we are not trying to do things like bill wormholes the way they did the same interstellar to get to a different place for trying to travel near the speed of light, so that we would actually be able to

inverse interstellar distances. I mean without that our colonization will happen in a very, very slow rate right, but one of the beauties of of relativity is, if you do travel news feed of like you, you can actually go arbitrarily far the human lifetime, he was a how's that possible. You can't go billions of light years. All you can actually because, as you can do this blade of light the way in which space and time change allows you to go in principle arbitrarily far. That sounds very exciting, but if we put that physics side of the issue in the middle, relations based on to the side yeah these deep engineering problem. How do you, terror form other planets, in how do you go beyond our local neighbourhood say without using the ideas relativity? So I think it's all products adding- and I think the ideas yo using solar sales of

if people have developed and you're trying to take that first step to mars, I think that's a vital and valuable step to take but yeah. I think these are fundamentally engineering, town or extending the human lifespan through biology research or may be right, Do you think what it means to be a human being into information and uploading, sir, It may be, not all the full resolution of a human life, but maybe a essential things like the deal, be able to reconstruct that human beings butts? you ask about mars. Us know you find, the dream of humans. being on mars stepping foot first, but also harmonizing mars. One. That's worth us fighting for yet users. I think what we have long been not always in the best way is a species of explorers

In the literal sense of travelling from one part of the world to another or in them more metaphorical sense of china. Travel through our minds to the quantum rome were back to the big bang into the centre of black holes, citing that's fundamentally part of of the human spirit, so I do think that's a vital part of our heritage brought forward in to its next incarnation. That's who we are Do you think they'll be a day in the sure where a human is born on mars and has to learn about his or her. Human origins on earth like they'll, have to read the book yeah. I don't think it'll be a book at that stage of properties to be uploaded into the head or something or you know imprinted into the dna and then they just sort of sense it but yeah. I think, there's there's what look

the issue raised before is divided one. Is it the case that any sufficiently advanced civilization destroys itself? Is that it's sort of a a commonplace quality mean that the other potential answer to the fermi paradox of. Why aren't they here, because by the time they got to the technological development where they could travel here, they blew themselves up, they destroyed themselves and that's a you know, and you know an unfortunate, but you know not a hard to imagine, possibility based on things that have happened here on planet earth, but but putting that to the side, I think it yeah that's the big obstacle, but potential and we will resolve the engineering challenges and- and you know, as you, as you probably modify my answer from before, when you said, is it engineering or physics? It's really both right? So so we will surmount the engineering challenges and that will then make the physics

challenges relevant it'll make a relevant to figure out how to travel near this bit of vital mega relevant to learn how to manipulate the shape of of space time and so forth. So so I think it's a multi eyes age process where it is engineering, ultimately physics, and if we stick around long enough. Those the challenges I think their ultimately gunnar surmount and then the physics side figuring out how to harness energy enough to travel outside the solar system. Wishes heck of a difficult journey, but even mars itself, Maybe because I was born, the soviet union was born with the you in looking up but the stars in the dream of like the highest of human achievement is the belief to fly out there to do you not to join the stars, I really like the you're gonna mars of and not just stopping for mars, and it wasn't until

Maybe I'm misinformed, but for me personally, It was until your mosque third talk about the colonization of mars. Did I realize like week we humans can actually do that any foresaw. The importance are somebody saying that we can do these million impossible. Things is immeasurable, because the fact he he place that into my mind and into the eyes and millions of others may be hundreds of millions and billions of others, young kids. Today I mean that that's gonna, make it a reality. I for some reason the excited even though my working ally that echoes of this annex by the idea that somebody would be borne as oversight. hang on mars and to look up and

you're, able to see with a telescope earth and say that's where I came from that that idea, scale to other planets to others, sisters, yeah, that's right! exciting, a huge, exciting thing, think you're write him in the vital thing is to dream. right. I mean it sounds hackneyed, but it is so important for for young kids for the next generation to to think about the things are seemingly impossible, I mean that's what makes them possible, and this is one which is concrete enough. I mean this is it is going to happen soon in terms of actually going to mars and then the next step of establishing some presence, some semi, permanent or permanent presence. This is this is not something that's going to wait till the twenty fifth century, but this is something

it's going to happen relatively soon, so I mean it could well be in your lifetime unlikely mind, but possibly in your lifetime, that that kid will be born and and and have the experience that that you describe so yeah, it's expect actually exciting and Actually I would love to go on mars and one of their early youth what it was one way as I'm happy to really why I'm sick of theirs lays out his guard. The mars now the attitude of the you about terror, thinking about like black holes. If I actually think about going to mars and being on mars and put myself in their fully, that's terror inducing

the idea of to be in this foreign world, where you can't come back. We've made this this choice. That can't be reverse of you know at some point it may be, but but in that guys that to me carries a deep sense of terror. You know I. I feel that sense of terror, every time iraq, jack talked about this on the road is you know when you leave a place if you're honest about it, like life is short. and when you leave a place, you moved a new place and you think of all the friends may be family you're, leaving behind as you drive over the hill, that really is good. Bye, agree, something Don't think of it that way when we're moving, but that really is good I too that life to the person you were to those all people may be if it's closed, you'll see that maybe ten fifteen more times in your life, and that is it in a you're saying goodbye to all that has all. In the same way, I see it.

Way more dramatic when you flying from earth and sake. It's goodbye to Duncan doughnuts this dialogue. It's good goodbye whatever at. Why pick those been some all those things that are special to earth? It's good, bye, bye! That's that's life! I suppose more What excites me about that kind of journey? Is it's a distinct. Contemplation of your mortality. Acceptance immortality, you saying just like when you take on difficult journey its accepting. You're going to die on day and minors Well do something truly exciting, yet I may I will I'm with you and I. strong believer that deep, underneath human Innovation! Is this, this time of our own mortality. There's this wonderful book. They had a great info

to make the denial of death by earnest becker and when you, we are aware of the way in which our mortality influences our behaviors. It really does added difference. Slant. Different kind of color to the interpretation of human behaviour yeah. It is funny that that book had a big influence, me as well as era and attend management therein and I ganz. When engineer perspective, I dont know how many people that book influenced, because if I talk to you about the fear of death and doesn't seem to be the fundamental to their experience- and I dont think on the surface, fundamental to my experience, but it seems like an awfully in terms of would talk about models and string, theory and theories in terms of theories of this matter. kirk experience of human life. It seems like a

have a good theory that the fear of death is the kind of is the warm at the core yeah? Well, I mean, and the terror management theory is that you make reference to him in the this. Is a group of psychologists, social psychologist who devised these very clever experiments, real world experiments with real people where you can directly measure the hidden influence of the recognition of our own mortality, many of them as experiments where they have group of people, a group of people bay and the only difference into two groups is that group, be they somehow reminded them in some subtle? they their own mortality. Sometimes it's nothing more than interviewing them with a funeral home across the street and influences their budgets, but it sell you don't think I note and they can find measurable effects that differentiate the two groups to a high degree of statistical significance and how they receive

and to certain challenges are certain kinds of questions that shows a direct influence the remainder of their own, more time. poverty and I've read a number of these studies and they are really convincing and so yo. I would say that reason why so many people would say that yeah fear of mortality, it's not front centre, my world view yeah. I everything It must doesn't really matter too much. The reason why they're able to say that is because this thing called culture has emerged over the course of the last ten thousand years and part of the role of culture is give us a means of not thinking about our mortality all the time of not living in terror, of the inevitable end which faces us all. So it's completely understandable that that's the response, because that's what culture is, at least in part four is at least possible that the

here of death. The terror of your mortality is the creative force that created of the things around us at this humans. They show think about from an engineering perspective, This is why I lose all of my robotics colleagues is, I feel like. If you want to create intelligence, you have to so engineer in some kind of echoes of this kind of fear of arm. In that, no your fears, the czech complicate award but kind of like a scarcity scarcity of time, a scarcity of resource

Is that creates a kind of anxiety like deadlines, get you to do stuff and there's something almost fundamental to that in terms of human experience? Yeah? Well, that's an interesting thought so you're. Basically, in order to create a kind of structure that mirrors what we call conscious Yes, you better have that structure confront the same kinds of issues and terrors, that's all that we do consciousness and suffering only makes sense in the context of death. If you want, I feel like if you want to fit to human society. If you're a robot, you want and defend a human society, you better have the same kind of existential dread. The this kind of fear of mortality, otherwise you're not going to fit in,

It might be, in my view, wild, but is at least the gourd. Talking about all the theories that are at least worth consideration. I think that's a really powerful one, a deafening one is resonate with me, and definitely seems to capture something beautifully, Like real about the human condition, and I wonder its of course sucks to think that we need death, appreciate life, but that's just may be the waiters, What's interesting, this robotic artificially intelligence system understands the world an understand the second law, thermodynamic and andrew, even in our visual towns will realise that, even if its parts are really robust. Ultimately it will do so,

great I mean to the timescales, may be different, but no way when you think about it, doesn't matter once you know that you are mortal in the sense that you are not eternal the time to heal, hardly matters, because it's it's either the whole thing or not, because on the scales of eternity any finite duration, however large, is effectively zero on the scales of eternity, and so maybe be so hard for an artificial system to feel that sense of mortality because it will rise it ignores the underlying physical laws and recognised its own, find it it and the us and robots drinking beers. Looking up at the stars and just you know, having a good laugh in awe of the whole thing there. That's a pretty good weight and talking about the fear of death who started talking about the meaning of life,

and ended on the fear of death. Brightest. Just incredible com has a really really enjoyed. It has been a long time coming a huge value, work of huge, Are you writing talk? Can ever? Thank you for listening to this conversation, brine, green, green support, support this gas. We check out our sponsors in the description and now let me leave you some words from bill. bryson physics is really nothing more than a search for ultimate simplicity, but so far all we have is a kind of elegant messengers. Thank you for listening and hope to see you next time The