The Joe Rogan Experience - #1233 - Brian Cox

Episode Date: January 28, 2019

Professor Brian Cox is an English physicist and Professor of Particle Physics in the School of Physics and Astronomy at the University of Manchester in the UK. Tickets for Brian Cox Universal Adventures In Space & Time available at: US & CANADA: https://profbriancoxlive.com Rest of World: https://briancoxlive.co.uk

That's very cool. Three, two, one. Yeah, a guy named, well, his online Twitter, or his Instagram handle is TGT Studios, and he makes these. I actually had one made for Elon. Elon Musk loved it, too. So we made him one.

He made one with, like, this very beautiful red wood. And those are, what are those things made out of, Jamie? Some diodes or something? Nixie tubesixie tubes yeah yeah that's right the old yes yeah he has to get them from russia that's uh he has them delivered over from russia so they might have like listening devices implanted in them as well yeah so brian good to see you man great to be back yeah great to have you back so tell me about this tour that you're doing it's a it's a world tour try to keep this sucker like a fist from my face there you go how's that that perfect yeah it's a world tour starts next week in um the uk and then we go

everywhere from the south island of new zealand all the way to the arctic circle to svalbard which is north the furthest north that you can go on a commercial aircraft in the middle we're in the states for a month in a mainly may and uh yeah it's it's about cosmology and about the questions that cosmology raises so if you're interested in the science of how did the universe begin, even questions of what may have been there. Is the universe eternal? Is there such a thing as before the Big Bang? What is the future of the universe?

How does complexity emerge spontaneously in a universe? I mean, we sort of take it for granted that there's a Big Bang and it's all hot and there's just this kind of hot glow of stuff. And out of that spontaneously in 13.8 billion years you get something like the earth with the civilization and life on it so how does that do we know anything about that i mean we do i'm asking the question rhetorically we know quite a lot about it so it's really about showing the size and scale of the universe but addressing those questions i think everybody has about what is about what does it mean to be human?

This tiny little finite life that we lead in a possibly infinite universe. How do you make sense of that? Well, it's incredibly exciting to me that there's a giant audience for this. And that what Neil deGrasse Tyson had been doing and what a lot of public touring intellectuals are doing now. They're doing these giant theaters. And these people are coming out to see these shows. And we're realizing that there's – I mean, I hate to use the term market for this, but there's a demand for this. And there's a lot of people who are incredibly fascinated by this. And it's spreading information.

It's spreading knowledge. Yeah. I mean, in the UK particularly, Wembley Arena, for example. Wow. You're talking about 10,000 people, 12,000 people in these shows. And you're right. They are coming. Although, you know, they're big shows, spectacular screens and all that.

They're coming for to think. They're coming to hear about what we know about the universe and nature. And I think, you know, I think I'm not surprised people are interested because these are questions that everybody asks you know i mean just why am i here you know everybody's asking that question but i my point is that there is a framework there's a framework of knowledge there are things we know about the universe so it is true that science scientists are not going to tell you why you're here and they're not going to tell you what the meaning of life is but there is actually a a there are things you need to know if you want to start to explore those questions for yourself i mean you need to know that there are two trillion galaxies in the

observable universe you need to know that the milky way galaxy has got 200 billion stars most of those stars now we know have planetary systems. We estimate there are something like 20 billion Earth-like planets or potentially Earth-like planets in the Milky Way galaxy alone. So if you're asking questions about what is my place in the universe, you need to know those things, first of all. It's a framework within which you can think. When you get to those numbers, when you're talking about trillions and billions and all those zeros, my brain just goes numb there's this lack of comprehension that i'm well aware of like those numbers get thrown about i go oh 200 billion

i think everybody does i think every scientist that no scientist can picture that number i mean he even the small number 200 billion which is the number of stars in one galaxy. And then when you say two trillion galaxies, you know, that's, I challenge anyone to be able to picture that. But it is the reality that we've observed. We've, you know, I mean, we haven't counted all two trillion, by the way. We have a thing called the Sloan Digital Sky Survey, which maps the positions of galaxies. So you know how much of the sky you've surveyed and you know how many galaxies you've counted. And then you can spread that across the wider universe.

And you get this picture of a vast and possibly infinite universe. We know that the universe, or very strongly suspect, that the universe is much bigger than the piece we can see. So we have good reason to think that's the case. Whether it's infinite or not is another question. And then that goes to your, you know, can you picture infinity? Well, no one can picture infinity. There's a weird thing as well about, you know, we say the universe began 13.8 billion years ago.

So that's a measurement. So because we can measure the speed that all the galaxies are flying away from us, You know, we say the universe began 13.8 billion years ago. So that's a measurement. So because we can measure the speed that all the galaxies are flying away from us, essentially. And then you can run time backwards, if you like, to find out when they were all on top of each other. And so it's a quite simple measurement. And we've done that. So we say the universe began 13.8 billion years ago. But actually, all we know really was the universe was very hot and very dense at that time and we have some theories that the universe was in existence before that and perhaps

some sort of circumstantial evidence and that means that actually the universe could could have always been there eternal and then when i talk to people sometimes they get a bit some people get upset about that some people would rather it had a beginning and the idea that it might have been around forever is more frightening somehow than the fact that it began and it's it's interesting the way that people's minds work what what terrifies you the most an eternal universe or a finite universe yeah they're both incomprehensible the the eternal universe if there was an eternal universe, does that negate the theory of the Big Bang? Or does it mean that there's a constant cycle of Big Bangs and then expansion and then recompression? Yeah, it could do. So those theories are back in

vogue. Some of those theories are back in vogue again. So yes, some of them say that there's a cycling universe. So the Big Bang is an event when space gets very hot and very dense and filled with particles. And that may happen again. Some of the other theories, there's a theory called eternal inflation, which is a theory that, and it's actually the most popular theory, I think, at the moment, for what happened, but why the Big Bang is the way that it is. It's got some very special features, the Big Bang, which we could talk about. But inflation is the idea that space, space-time was around before the Big Bang,

and it was expanding extremely fast. And it was doubling in size in the most popular of these theories, every 10 to the minus 37 seconds, which is 0.00000 with 37 knots, one of a second. So it's an unimaginably fast expansion. And then the idea is that draws to a close, so it quite naturally sort of dies away and the expansion slows down. And all the energy that was taken that was causing that expansion sort of gets dumped into space and heats it up and makes particles,

and that's what we call the Big Bang. And those theories, the slight extension to those um say that that slowing down just happens in little patches so most of the universe the overwhelming majority of the universe is still inflating at that insane speed and the just little patches stop and they're big bangs so you get multiple universes a multiverse it's called the inflationary multiverse and we are in one of those bubbles and that's one of the more popular theories that's another one i mean that right now i'm aware of what you're saying i i can i can sort of visualize it in some sort of a graphic form, but it's incomprehensible. Like my mind doesn't, it doesn't have the capacity to expand the sense of distance and size to that,

that grasp. Is this because of just the way we evolved? We evolved here on earth to deal with the space that's in front of us. And now over the course of, you know, industrial civilization and education we're now grasping these concepts that are so alien to the reality the the tangible reality that we exist in every day i'm sure that's right um the the you know even very simple things like you go back to

the greeks so aristotle and there's great, very clever people. But they thought the Earth was at the center of the universe. Why? Because it feels like it's at the center of the universe. It feels like we're not moving. And that's quite a deep point, actually, in physics. It's like, why is it that we're flying around relative to the sun very fast at whatever speed it is, 18 miles a second or something like that? And the whole solar system is going around the Milky Way galaxy and and so on why is it that we don't feel it and then the greeks quite naturally said well because we're at the center of the universe they also said everything falls towards the earth

so therefore the earth must be at the center it's it's natural right and and actually it's quite a deep uh thought to understand why it doesn't feel that we're moving you have to go all the way to Einstein really for someone to take that very seriously and he well he said actually he said well this um there's a great little explanation in Stephen Hawking's brief history of time about this that the idea that you can't tell whether you're moving or not demolishes the notion of absolute space so if we think about space if i said space to you or most people i suppose you'd think the way that newton did of a big box within which things happen and that's got to be that's a natural picture of space and the universe isn't it is a thing in

which all the planets and galaxies are placed but um in in the brief history of time harking says well imagine bouncing a ball so we bounce a ball on the table now, a tennis ball. So I drop it and I catch it again. So let's say I drop it and it takes a second to bounce up. So in that second, the Earth has moved about 18 miles or so in space around the sun. So you could ask the question, did that ball return to the same place in space or not? And the answer is, you can't answer it you it does from our perspective but from the perspective of someone watching the earth go all the way around the sun

it went up i caught it again it had moved 18 miles and then from some other perspective it would have done something else so the point is you can't say this is a point in space it came back to the same place because that just depends on your perspective depends on whether you're watching the sun the earth go around the sun or whatever it is so so einstein said that means there's no such thing as absolute space which kind of follows if you think about it but that's a difficult it's it's a cool but difficult thought process right i mean that's that's essentially what's happening when you're on a plane i mean if you're throwing a ball up in the air and catching it on the plane it's happening in a much smaller scale right yeah yeah i mean you're flying at whatever 600 miles an hour

relative to the ground but it doesn't seem like it when you're sitting there yeah and einstein elevated that to a principle and said if you're moving at if you're not accelerating you're just moving at a constant speed in a plane or now i. I mean, that's essentially what we're doing now. We're moving around the sun at effectively constant speed. Then you can't tell. So there's no experiment you can do. We could look at the decay of a radioactive nucleus or some electricity and magnetism or bounce a ball, have a pendulum, whatever it is. And there's no experiment you can do to tell you whether you're moving or not.

Therefore, that concept has no meaning meaning because you can't measure it and that that's led einstein to relativity so that that's the the basis of general relativity which is our best theory of the universe now why is it that we think that the known universe is larger than we can observe? Well, one point is that it's expanding and we always see the same radiation out there. So the glow of the Big Bang. But there are some deeper reasons. um the one from the theory of inflation the the the the best way to explain the universe the properties that we see is that it's very much bigger than the piece we can see so for example we measure space to be what's called flat i don't even have to say what's called flat it is flat

so if you imagine slices of space, let's imagine slices of them at different times. So you just slice the universe and say, there's a big sheet like this table. There's a sheet of space and there's another sheet and another sheet. And it can have a geometry, right? It can be flat like a tabletop or it could be curved like a sphere or it could be curved in the opposite direction,

sort of like a saddle or a bowl. And we can measure that. And when we we measure it we see it's absolutely flat and that's a very unusual thing for it to be like um it requires because what what einstein's theory says is that the the shape of space that the curvature of space is determined by the stuff that's in it that's that's basically einstein's theory of general relativity put stuff in space and it curves it and bends it and warps it and stretches it and so on and what we find is that there's precisely the right amount of stuff in the universe to have a completely flat universe and the the explanation the most favored explanation for that is the universe is way bigger than the piece we can see. And so it's like looking at a piece of the earth.

If you look at a little one mile square of the earth, right, then it's flat, right? You have to look at big distances, kind of of order the radius of the earth, you know, bigger than one kilometer anyway or one mile to see that actually you're on a curved surface and that's one of the ideas about the the universe and why it appears to be the way that it is because it's way way bigger so we just we're just looking at a little piece and that's why it looks flat and that's one of the ideas now when you say flat like that my my brain doesn't understand this because from our perspective when you look up at the Milky Way, you see all these stars all over the place. So if you're saying flat, like how much height and what are you saying

in terms of like the way to measure it? The best way to think about it is not to think of three dimensions of space because then we can't picture it. But you can think of two, like this tabletop. And that's all right. We just forget the other one for now. And so you know what flat is on this table i mean you could define it so you could say for example that if i draw a triangle on the top of the table then all the angles add up to 180 degrees so that actually defines flat if you did that on the surface of the earth with a big triangle

then the angles wouldn't add up to 180 degrees or you could draw a circle and say what's pi so pi is the ratio of the circumference of a circle to its diameter that's only true on a flat surface it's different if the surface is curved so you can define flatness so when you but when you're saying flatness how what is the height and what is the width like if you're talking about it as if it's a table, there must be some sort of a, there's a dimension to it, correct? Oh, yeah, there's a third dimension of space. Right. But the same applies.

It's just a generalization of geometry then. So you can, the point is we can picture it in two dimensions. But you can draw, you can quite quite literally you could imagine sending light beams out and we do this measurement actually we can look at the the the most distant light we can see which is something called the cosmic microwave background radiation which is if you imagine looking out if you look at the andromeda galaxy which we can see with the naked eye here in la you can see that it's the most distant object you can see with the naked eye here in LA, you can see that. It's the most distant object you can see with the naked eye. And it's about two million light years away or so, which means the light took two million years to get to us.

So it's a long way away, but it's very big. So as you look further out into the universe to more and more distant galaxies, you're looking further back in time. Because you look at something that's a billion light years away, then the light took a billion years to get to us so you see as it was a billion years in the past and we can actually look so far out that we can see almost back to 13.8 billion years ago which is very close to the big bang so we can look to light that began its journey before there were galaxies and that's the oldest light in the universe which is by the way one of the one of the pieces of evidence when people say i don't believe in the big bang the answer is well you can see it so it's just there you can see it we have pictures of it um that light it turns out that there are sort of structures or ripples in that

light um which we can use as a ruler. So quite literally, as a ruler on the sky. And then because that light's been traveling through the universe, we can see how that ruler's been distorted as the light has traveled through space. And so we can infer whether space is flat or curved or how it warps, if you like, just from that measurement. It's a beautiful measurement. Is it possible that in the future we'll be able to see past 13.8 billion years?

Not with light. Not with light. Because the picture is that before, it actually was released 380,000 years after the Big Bang. It's a very precise number. You might say, how do you know that? Well, before that time, the universe was so hot that atoms couldn't form. So you had a soup of electrically charged particles it was just too hot for electrons to go into orbit around nuclei so the universe was opaque to light so you just couldn't it's like one almost like a big glowing star if you like and then when it was expanding it cooled past the point where the atoms could form

and at that point it becomes transparent really almost instantly in a cosmic time scale and so the light could then travel in straight lines through the universe and we can see that light so we see the light from that time but further back than that it's opaque so you can't see past that with light but you can potentially with gravitational waves which is this measurement that got the nobel prize a couple of years ago the ligo experiment here in the united states and that see it looks for ripples in the fabric of space and time and in principle if we had a big enough detector you could see the ripples from the big bang so you could you could

take an image of the big bank in gravitational waves which would be but you need an enormous sort of space-based detector that we're not going to build anytime soon now obviously this is all through equipment and technology that's been invented over the last few hundred years and perfected is it possible that things could get better and you could get some some ability to detect things even in a far more distant way yeah i mean the i mean gravitational waves are incredible i mean einstein predicted them in 1915 never thought they'd be detected because you need such a hyper you need lasers they didn't have lasers but i think ligo this experiment which is half in

near seattle in washington State and half in Louisiana. So they've got two detectors. And they're basically sort of, I don't know, three mile long laser beams that just sit and measure the sort of stretching and squashing of space as the ripples in the fabric of the universe go through. And what they've been observing are collisions of black holes. universe go through and and what they've been observing collisions of black holes so you can imagine how extreme like a colliding black holes it's an incredibly extreme event so it shakes the fabric of the universe and the ripples come across the universe and these laser beams which are just basically rulers can detect it they just sort of ring almost like you know just vibrate as the ripples go through.

In space and time, Kip Thorne got the Nobel Prize last year for this. He was one of the greatest living physicists. I once saw him describe it as a storm in time. So you've got this time storm. It's a beautiful image. So that technology is incredible. Because the change in length, I can't remember the exact number, but it's way, way, way less than the diameter of an atomic nucleus. So the change in length of the beams.

It's tiny measurement, but we can do it. So this collision of black holes, the idea that you can detect that. Yeah. Yeah. The paper, the first paper they they published there are two black holes and they were about 30 times the mass of the sun each and they're all between each other and spiraling in towards each other and they accelerated at one point they were approaching each other at one third the speed of light and they accelerated to two-thirds the speed of light in a tenth of a

second and then hit each other and the explosion the energy release was i think i'm right it was something like 50 times the energy release that the power of all the stars in the observable universe glowing and it was something like 50 times that amount of energy for a tiny fraction of a second. But it's an unimaginably violent event. And that's why our detectors can see the ripples that that makes in space and time. And we detected two or three of them now and also two neutron stars colliding. We saw that as well with it. So it's an incredible machine, which is why it got the Nobel Prize.bel prize now there's a super massive black hole at the center of every galaxy yeah yeah there's

also other black holes that aren't necessarily in the center of galaxies yeah so these little ones were little you know a few times the mass of the sun and they're from collapsed stars so they are stars at the end of their life very bigger than the sun more massive than the sun but they run out of their fuel and they start to collapse because gravity squashes them and if they're sufficiently massive then there's nothing that can stop the collapse and so they collapse as far as we know to a point right and essentially an infinitely dense point we don't really know what happens at the we don't know what happens right in the middle but they collapse to such an extent that there's a region around it where from which light can't escape and that's a so nothing can

escape and that's a black hole and what happens to them do Do they travel? Are they moving through space? Yeah, they're still stars. Right. So they're still there. They're surrounded, this region where if you fall in, it's called the event horizon. And if you go across that horizon, then you are going to the center. There's one way of thinking about it, which is quite cool, which is that the time and space sort of flip is one way of thinking about it which is quite cool which is that uh the time and space sort of flip is one way to think about it so in the same way that we are going into the future now

so so we're going to tomorrow there's nothing we can do about it we are going to tomorrow um in the same way if you fall in across the event horizon of a black hole you are going to the the singularity it's called so that's that's your future. Every line of your future points to the center of the black hole. So it's kind of the ultimate of no escape, the ultimate prison. You're going to get squashed to an infinitely dense point. But not every star becomes a black hole at the end of its life? No, because if something like the sun. We have a small star.'s quite small yeah and when it collapses there's a there's a sort of a pressure a force

if you like which is caused by the fact that electrons don't like to be very close to each other so it's called the paoli exclusion principle but essentially what happens is that so as they get squashed closer and closer together they move faster and faster to sort of get out of each other's way if you like and that makes a force which holds them up and so that creates what's called a white dwarf star so so you can have a blob of matter they're about the size of the earth but they're about the mass of the sun. And so that's for smaller stars. They end up as these white dwarf things, which are very dense objects. There's another version, which is called a neutron star,

which is the same thing, but for neutrons. And they move faster and faster. So if it's massive enough that it overwhelms the electron thing, then the electrons sort of crush into protons and turn into neutrons and the whole thing starts again and so a neutron star can be you know at least one and a half times the mass of the sun let's say but it can be about what 10 miles across so so that's an incredibly dense ball of matter held up by this the neutrons moving around it's got a fancy name it's called neutron degeneracy pressure but that's what it is but if you go even bigger then even that can't

hold it up and as far as we know then there's no known force that we know of that can hold hold the thing up if it's if it's too massive and so that's when it just almost winks out of existence if you like it collapses and collapses and collapses And that's when you get a black hole. We try to put that into perspective. The sun is a million times bigger than the earth. Yeah. And this neutron star is, would you say one and a half times the mass of the sun

but 10 miles wide? Yeah. Yeah. And there's loads of those around. They're called pulsars. So we see those all over the place. The first one that was discovered was called LGM-1 because they spin very fast.

And it was called LGM-1 because it's a very regular pulse and they thought it was Little Green Men. So they called it, kind of jokingly, Little Green Men-1. So, yeah, we've seen that there's one called the Crab Pulsar, which is in the Crab Nebula, which we saw the supernova explosion. So that's when one of these stars explodes at the end of its life and then collapses to form a neutron star. And we saw that in 1054 AD.

Wasn't there some speculation that our solar system at one point was a binary star system and that one of those stars had become a dwarf i don't know um someone had read something about that in relationship to the dense object they believe is outside the kuiper belt yeah i mean there's some evidence there's a bit of evidence that there's something out there, yeah. Because of the periodic extinctions and things on Earth, you get periodic bombardments from out in the Kuiper Belt. So yeah, I think one of the theories is that... Periodic extinctions. Well, yeah, so for example, there have been mass extinctions on Earth when a lot of the life died.

And we don't know what caused all those, but sometimes they're impacts from space that seems clear and so yeah there are theories that there's something orbiting out there which can disrupt all these objects out in the Kuiper Belt that sends loads of comets

and asteroids inwards to the inner solar system and can cause havoc and so there's some people look at those theories I mean I don't know it's one of those it is a possibility that there's something out there the speculation was that there's something out there's correct me if i'm wrong something called a galactic shelf like that it gets to a certain space and it indicates that there's something far larger out there uh yeah i mean

i think i don't know the exact about the stellar sized or mass objects out there i don't know that i mean there are some sort of suggestions there's another planet out there a big planet for example but you're right there can be there can be stuff obviously way beyond the kuiper belt and we're talking you know a light year away or something like that now it's it's interesting because it's incomprehensible, the distance, right, in our minds, how far that must be out past what we used to call Pluto. But for whatever reason, that becomes more interesting because it's in our neighborhood. Whereas if they find some distant star system and it might have a planet that's's similar to earth that doesn't seem as compelling for whatever weird reason no yeah i mean i think the the planets around alpha centauri

proxima centauri which are the closest stars it seems like there are planets around those now and i think that was interesting because we could conceive of going there right and there was this idea steven hawking actually and some others before he died had this idea called breakthrough star shot which is the idea to send a little probe out to the center of the alpha centauri system and i think in their view yuri milner as well the the you know the entrepreneur wanted to do that and uh there is i think it's something like 100 years travel time or something with with the with our current technology and they pointed out that you know we don't do that now we don't think 100 years in the future but if you go back when people were building cathedrals people used

to routinely start projects that would take 100 years to bear fruit and so we could imagine going there and that's that then becomes fascinating i think because then you've got a solar system another solar system that you could go and visit conceivably conceivably yeah i mean what kind of speed are we talking and how long would it take to get there well yeah i mean so it is i think that the idea was about 100 years to get there so it's going you know four light years or so in 100 years or whatever that is. So you would have to essentially do what they did in the Ridley Scott alien film and put people into some sort of a robot probe. It wouldn't be a crude probe.

Wouldn't be possible for a crew? Well, it is. But you'd have to freeze them? Yeah, that's always, you know, when you talk to engineers, you had Elon on, didn't you? Yes. Engineers always say, you know, physicists go, well, it's possible in principle, so over to you. You know, you do it now.

There are no laws of physics that tell us we can't do it, so we just do it. Right. But, you know, it's… That's a weird relationship between the physicists and the engineers. Yeah. Yeah. Yeah. But, yeah, in principle, you're right.

If you can send a little robot spaceship there, you can send a crewed spaceship. I'm of the opinion as time goes on and augmented and virtual reality gets better and better that it doesn't really totally make sense unless biology being affected by radiation or by the speed of travel or even by food, we can send something out there and almost be there by virtue of goggles, virtual reality goggles or something else. Yeah, you hear that. In science, at the moment, space science, we have this debate a lot actually because, of course, space probes like Curiosity that's on science at the moment space science we have this debate a lot actually because of course um space probes like curiosity that's on mars at the moment that's really cheap compared to sending people to mars and so quite often the scientists who want to find out about the world will say well we should spend it on robots we shouldn't spend it on people i think crude space exploration is in some ways,

I mean, it's clearly true at the moment that humans can do more than robots so we can explore the place better. For now. Yeah. But I think it has to be, it's about something else. I mean, it's about, and it's not only, it's about living and working off the planet,

which I think is quite a persuasive argument, actually. We've already industrialized near-Earth orbit, so it's already a multi-billion dollar industry. Communication satellites and weather satellites, GPS, whatever, we're already up there. And so learning to live and work in space is, I think, a natural extension of our civilization. Plus the fact, if you talk to elon

or jeff bezos they point out that the amount of resources available just slightly above our heads is vast and so i remember i talked to jeff bezos actually once and he he thinks really simply and he said you know for example in the asteroid belt there's enough metal i think to build a skyscraper example in the asteroid belt there's enough metal i think to build a skyscraper what is it a something like 800 stories tall and cover the earth in it right if you want now we don't want to do that but his point was that that the energy from the sun is all up there the resources are up there so you could almost imagine trying to zone the earth residential at some point in the future to protect the planet and do your heavy industry off the planet for example and these sound this sounds like science fiction

except that now spacex and blue origin those people have got reusable rockets so suddenly the economics become sensible so i think i think i think expansion is good and i think we will expand and i think we will expand outwards because there's not much room left on this planet to expand. So I think we'll do it. That's a whole different idea. It's not about gathering scientific information. It's about a

frontier and all the benefits that come from operating as a civilization on a frontier which we've lost on the Earth because there is no frontier left and so i like that idea that mars and when you talk about mars especially with elon he's right that that's the only place you can go so there is no other planet we can go to other than mars you can't go to jupiter or saturn you can't go to mercury or venus so if we want to go

somewhere and expand our civilization it has to be mars and everything's there that you need so but that that's a different thing saying you want to find out stuff you're right if we just want to find out stuff then you send robots but as far as expanding actual civilization and bringing it to another place one of the things that freaks me out is people get depressed about living in seattle i mean you're gonna live on mars i wouldn't i agree yeah it'd be a horrendous thing it's like the it'd be like the western frontier it's the frontier when people cross the states yeah an incredibly dangerous thing to do but when people cross the states they still got to wyoming and beautiful places and colorado and yeah but it was hard yeah i

wouldn't have wanted to do it but once you got there there's a river and there's trout in the river and the the meadows are green and it's it's right i mean i agree with you right i mean i'm not going to go there till there are vineyards and hotels and things but however it is true that there are people who like the challenge and what is true about mars it's interesting actually because we know something about the history of mars now quite a lot about the history of mars and it's certainly clear that there was water almost certainly oceans and rivers so and that water is almost certainly still there so i would say certainly still there well they have found large quantities of ice now right yeah so there's certainly ice there may even be pockets of liquid water below the surface somewhere.

So couple that with all the minerals and the resources that we know are there, and you have everything you need. So that's the thing about Mars. It's quite nice relative to everywhere else other than the Earth. You can't go to Venus. You just melt. It's, what is it, 400 and something degrees and 90 atmospheric pressures. So Mars is quite nice.

But I wouldn't go there. I agree with you. What's the gravity of Mars in relationship to Earth? It's, what is it, about a third, I think. Third. Right, yeah, something like that. So it would still have a significant, like, weakening effect. Like if you went to Mars and then somehow or another in the future they were able to get back to Earth,

your body would have a real problem with that, right? It would, but there is still gravity. It's a bit more than a third. I can't quite remember, but it's something like that. But yeah, so there's still gravity. So there's gravity. There's some protection from the – you'd probably want to live in the caves actually or something like that you'd because there's no magnetic field there so it's quite a high

radiation environment but not too bad it's further from the sun than we are it's not too there are places on mars that there's a very deep crater called hellas which is a big impact basin and at the bottom the the it's so deep you could fit everest in it so you put mount everest in there the summit of everest wouldn't reach the rim of the crater so it's something like i don't know what it is seven miles deep or something six miles deep so you could go there and at the bottom the the atmospheric pressure is so high that you could just about have liquid water on occasionally on the floor of that crater. And it's quite warm sometimes.

It can be 20 degrees. Really? Yeah, there, Celsius. Wow. That's better than Minnesota right now. Exactly. Minnesota's experiencing a serious cold front. That's right, yeah.

So it can be warmer than Minnesota. And so there are places where it's not horrendous on Mars. So the Martian is kind of realistic in that sense. Sort of. Bits of it. Do you watch those movies and shake your head? I like them. Do you?

I like science fiction. Right. So, yeah, I don't sit there. I grew up with Star Wars. That was when I was nine years old or something. It's funny watching it now. Yeah, I'm not having this. wars that was my when i was nine years old or something it's funny watching it now yeah i'm not having this i did i did an argument with neil degrasse tight not an argument but debate with him

about lightsabers once because i claimed that they're physically in principle they're possible um and he was trying to say that they aren't but they are would they have to loop back around because the light's not continuing to like the fact that it goes to a certain distance and pauses we don't have a mirror or something i guess yeah something would have to be the end of it right that's true so it wouldn't it'd be a different kind of light so the only point i was making is that photons particles of light can bounce off each other so we see that in really high energy experiments in particle accelerators we can collide photons together. So my point was a bit of a pedantic physicist one, because it is true that light can bounce off, it can hit light, but very, very high energy.

But when they press that button, it goes to a certain distance. Yeah, yeah. That's engineering. Right. I agree with you. I agree with you. The distance thing doesn't work. There's no mass to it right

so as you're swinging it around you wouldn't have the leverage of a long thing so why not make it really long because it wouldn't be difficult to swing around like you could stab someone with a lightsaber a mile away that's right that's just a, isn't it? Yes. Why make it so short? It's ridiculous. You have to swing. You have to be close to hitting a person with it. That's a silly design. You are picking holes correctly in the engineering part of my...

The only point I was making is the physics is that... Which I think is quite interesting is that light can bounce off light. Yes. That's the point. But there would have to be something that causes it to stop at bounce off light. Yes. So, but it would have to, there would have to be something that causes it to stop at the very end. Yeah. Yeah. Yeah. Which would be,

you're right, it'd have a mirror, but it wouldn't look cool would it, if there was a kind of thing with a mirror. Well, what drives me crazy about Star Wars is not the lightsabers, it's the lasers when they're shooting the guns. I'm like, why can I see that when I can't see bullets? This is supposed to be

way faster than a bullet. Yeah. Like, why is it easy to see this? Because it's like, you can duck. You can get out of the way of those things.

They're really slow, aren't they? They're so slow. I would be so angry. I'd be like, this is so dumb. I could go warp speed in this Millennium Falcon and travel the speed of light,

but for whatever reason these lasers are so slow that you could duck out of the way of them that's so dumb and it's not only star wars it's everything every single film does that yeah yeah why it's like it's like films like also i worked on one of these films years ago uh sunshine oh that was a great movie very very underappreciated movie. Yeah, I think so. I think it's a brilliant film. But in that, so they asked me, and Danny said, I want to do it right, so I'll do the spacecraft without any sound. So when it's traveling through space, it'll be silent.

And it looks shit. When you watch it, it's the same when you try and film astronauts, and they're in zero-g, and they always move slowly. It's like, why? You're right. You'd be able to move very fast. As fast as you want. Yeah.

But it looks silly. So there's kind of a, I suppose it's what audiences have got used to over the years. And so in the end, you have a, when the spacecraft goes fast. Apart from 2001, which didn't do it. Yeah. It was silent in 2001. which didn't do it yeah silent in 2001 well kubrick was a stickler for science and for he was apparently he would do complex mathematics in his spare time what a fascinating guy that must have been yeah i read that they just um someone just found an interview didn't they

the other day where he explained the ending of 2001 i didn't say that i saw it yesterday actually and it was it was kind of a really simple version of it he just said well the super intelligent beings take him in and put him in a zoo basically and watch him grow old and then send him back to the earth as a super being that's the that's the worst explanation at the end of 2001 I've ever heard. But it was Kubrick's. That's what Kubrick said. So he falls into the monolith. They just put him in this room, which is kind of a bad version of a French chateau or something. Watch him grow old and then send him back to the earth as a super being.

Wow. Okay. That was Kubrick's version. How strange. It's a weird genre right because sometimes people get things right like didn't hg wells predict a significant amount of scientific inventions in the future well there was his i mean it depends which one doesn't it there was a moon one wasn't there he did a journey to the moon i mean his time machine is yeah not right that i'm not gonna be able to do that really worked out yet

but yeah i think it's i i always like science fiction yeah i like arthur c clark a lot you know because i i think it is you're right it's it's a a form that you can let your imagination wander and address things without restriction. I think. Did you like the alien series? I loved it. Yeah.

I saw alien when I was, uh, when I was at school, it was 1979. Right. And we had a school film club and in the seventies, they weren't like they are now, you know?

And so the first films they put on the three films, I was 11 and it was alien apocalypse now in life of Brian. Wow. Which I, so that was my introduction to cinema wow well those are three great choices but i feel like ridley scott's original alien is probably one of the greatest horror science fiction movies of all time and one of my all-time favorite movies but i really like the newer ones as well like i like prometheus and i really like

covenant the the last one yeah prometheus i don't know i yeah it's not the best one i love it i like what they're trying to do with it the whole idea about the engineers coming back in time and that's that's why i was disappointed with it because i thought the setup the opening is brilliant and i thought this is just going to be brilliant and then i thought it just lost its way and it was a disappointment because it could have been so brilliant. Yes, I agree with you. Yeah, the beginning was fantastic. But I think Covenant was more exciting.

And, well, it's also preposterous. Like, if you went to another planet, like, the last thing you'd be doing is just breathing in the air, right? I mean, we'd have to be really careful. If there was a life on the planet, we'd have to be really careful to a not to contaminate but b not to be contaminated right yeah yeah i mean there's also i mean you know the other thing in science fiction films is gravity because you always even in alien you always just say the spaceship's got gravity again there's only 2001 right where everybody floats around yeah because all has a spinning thing right Right. The spaceship has gravity,

and then when you land, the gravity is exactly like Earth. Yeah. Perfect. Yeah. No. It's ridiculous. Yeah.

I mean, what are the odds that you would find a planet that is exact? Like, even if a planet was one and a half times the size of Earth, it would have far more gravity. Right?

And that's really common for a planet to be, like, just a little bit bigger and then we would be like everywhere we'd be walking we'd be we'd be getting crushed right i agree with you yeah well i suppose that's not the point it's about ideas isn't it science yes and you know this whole idea where you're just supposed to let it let the you know let the story play out. Well, I mean, Sunshine was, you know, the premise is silly. I mean, the premise is the sun is dying and we're going to go and fix it. So both of those things, it fails on its first line in terms of realism.

But the idea is that it's not about that. It's about the sun as a god in some ways so it's about our response to the power of nature and it's about deifying this thing and worshiping it and how ultimately you go mad if you remember the film there's pinbacker who's the first captain that went to the captain the first mission to go and restart the sun which is the mad bit but then became a religious fundamentalist essentially and then decided it's a fascinating idea that he decides that to bring meaning to his life he will become the last last man the last human and so he wants to be the last he wants the sun to die and he wants it to take humanity with it and he decides to

make that happen so he stays there waiting for the second ship and i like those ideas that you know that what's your reaction to the power of nature this happens in one of the things i do in my shows i'm not being a commercial person i've just thought of it one of the great things about cosmology is that it is terrifying in the truest sense of the word i mean we talked a bit about the size and scale of the universe and black holes colliding and those things you know it is very frightening but also the i think the the act of trying to understand our place in nature and the size and scale of the universe and our our tiny presence within it is valuable it's a it's a so that you can be terrified but also

inspired and interested and it's part of if you want to find if you want to ask questions about what it means to be human and means to be alive then i think you find the answers in confronting that reality which is that we live in a terrifyingly vast universe the powers in the universe that we cannot comprehend as you said but that that's what you've got to face because that's reality so you can't hide your head in the sand and just duck it and it sends some it can send some people crazy. I'm sure. And it is really interesting that we need that suspension of disbelief in order to sort of make a film on space.

You almost have to go, well, this isn't really how it would be, but this is how you have to make it in order to fit it into a two-hour movie. Yeah. And then the film as with sunshine becomes about you then you can have the film about something else yes because it's not really about that well did you like a event horizon yeah i did actually i thought that was ridiculous i haven't seen it for years i always wanted to ask about their their concept of propulsion that you that almost like space would be flat, you would fold space over, and you would intersect those two points,

and you would be able to travel vast distances instantaneously, right? I'm doing a terrible job of explaining, I'm sure. But is that a concept that people have actually considered? Yeah, you can, in general relativity, so Einstein's, I should say what it is, Einstein's theory of general relativity is our best theory of space and time. And so it really is, as we've talked about before, it's you imagine space and time as a sheet. Just imagine it as a thing, sort of literally a sheet surface. And all the theory says is that if you put matter and or energy into that then it curves it and distorts

it and it can stretch it and make it shrink and so it's the response of space and time to matter and energy so if you if you the the simplest version would be the the sun so you put a big spherical ball of stuff in there and it warps space and time such that the the nice straight lines something just traveling minding its own business through that warp space and time such that the the nice straight lines something just traveling minding its own business through that warp space turns into an orbit and that's why you can actually kind of see things that are behind the sun yeah okay so light bends around the sun and because it's just traveling through the curved space the earth goes around the sun because it's just rolling minding its own business through the curved space so um an example would be you might

say well how does curved space how can that give rise to something that looks like a force which is gravity so the best analogy i know of is to think of walking around on the surface of the earth so if you stand on the equator of the earth and you with your friend and you say we're going to walk due north so we're going to set off let's say we're a thousand miles apart on the equator and we're going to walk due north and what's going to happen so you walk in straight lines you don't change direction you don't do any accelerating but the straight lines are the lines of longitude on the surface of the earth so as you go further and further north you get closer and closer together and if you carry on to the pole you bump into each other but But nothing's happened.

There's no forces acting. It's just that you're moving on a curved surface. And so you get closer. And that's basically Einstein's theory of general relativity. Now, why did I start talking about that? Event horizon. The idea of folding.

Oh, yeah. So all you have to do to those folded kind of geometries is you have to try and specify how where you would put the matter and what kind of stuff you'd put there to make the geometry fold in that way and you can do it you can do it so you can you can write down that geometry it's called a warp drive geometry i think it's called it's in textbooks so you can do that to have a warp drive the question becomes what sort of stuff would you have to actually put into the real universe to make it warp in that way and um it always it usually turns out that it's the kind of stuff

that doesn't exist right but it has properties it's my sort of matter or sort of energy that has properties that do not exist in nature as far as we can tell but you can still write the geometry down in einstein's theory so if you have a significant force or mass or whatever it is if you had that stuff that doesn't exist it is a concept that yeah so the geometry exists so you can you can you can do it and you can do the calculations and you can see the calculations, and you can see the warp drive. You can construct wormholes that connect distant regions of the universe, which you could use as time machines. You can do all that in the theory,

but in nature, you'd have to have the right stuff to do it. But that stuff is not real. That seems to be the case. As far as we know. Yeah. Now, what would have to happen? real that seems to be as far as we know yeah now what would have to happen like you would have to have enough power or mass to to be able to fold those two things together like it tends to be weird stuff like um stuff that has a negative pressure or something like that so stuff that

has physical properties that are just bizarre and that no matter our energy that we know of in the universe has so that to make to make the geometry happen but it's conceivable in theory that this could exist even though it doesn't it's a it's a it's a debate ultimately um so wormholes is a good example so that would be quite literally it was talked about the surface of the earth so you fly to australia from la and you have to go quite a long way around this edge of the earth or you could tunnel straight through and get there quicker right so you can that's a worm james got a little graphic up there there it is there's a wormhole so you could go all the way around the edge or you could cut take the shortcut so the question is so you can do that in einstein's theory you can write down that geometry and and there it is so the first question is can you make it and as

we said we don't think that stuff exists right there's a second set of theoretical bits of theoretical work which if you had a wormhole then what would happen if you tried to travel through it and what seems to happen is that they become unstable the moment anything tries to go through. So you get kind of a feedback of stuff going through and through and through and through. And so it collapses. And there's a great book by Kip Thorne, actually.

We just mentioned him. He got the Nobel Prize last year for the gravitational waves. And he wrote a brilliant book. I think it's in the 80s called Black Holes time warps where he talks about the the answer is we don't fully know but most physicists think that even if they existed they would be unstable and as soon as you even try to transmit information through them send a bit of light through then there would be this sort of feedback and they'd collapse and ultimately the reason we don't really know absolutely is because you need what's called a quantum theory of gravity and we don't have one so we don't have the theoretical tools to be absolutely sure

that these things would be unstable or don't exist in nature but we strongly suspect that they don't if they did you could build a time machine so there's stephen hawking wrote a paper called the chronology protection conjecture um and conjecture is the important word so he the conjecture basically was that the laws of nature will be such that you can't have stable wormholes and you can't build time machines and if you send something through it it would destabilize it. Yeah. And if it didn't destabilize it, how would your physical body deal with the stress of that?

Well, it doesn't have to be. You can build them. That's called the tidal gravitational force. So it's the difference in gravitational pull across your body, which is one of the things that gets you if you fall into a black hole. So before you actually get to the singularity, you can get's called spaghettified it's a technical word so you get and it's just like the moons you know the tidal effects on the earth which is quite small but they still raise tides on the oceans so that can be a if you think about something like a black hole that can be a massive difference in gravitational pull from your head to your feet

and so it can stretch you out and so but you can with wormholes you you can you can write the geometry down in einstein's theory such that you could go through so so you don't have to be destroyed or anything weird happen to you would you have to have some something protecting you some force some some sort of a yeah you just literally you fall through i mean it's so so you know if they were if they would exist you just you just go through you sit in a little spaceship but you you you wouldn't there's nothing inherently in them that says that you would be ripped apart or anything like that but what are your thoughts on on alien life on life outside of this planet is there something you think about yeah i think there must be um

even in the solar system i would not be surprised if we find microbes on mars or on some of the moons of jupiter or saturn where there's liquid water like europa yeah and the reason is if you think about the reason i think that and it's a guess is because if you look at the history of life on earth then so earth formed and it was just a there was no life it was a ball of rock and almost as soon as it cooled down, we see evidence of life. So certainly 3.8 billion years ago, possibly even further back than that, we see evidence of life on Earth. So somewhere along the line, geochemistry, active geochemistry, became biochemistry on Earth.

And we have some idea that if you get gradients of temperature and acid and alkaline and the conditions that are naturally present on the surface of oceans then complex carbon chemistry spontaneously happens so we have a we know that life almost certainly we know that life began on earth i mean the other option is it came from space or something like that, but it probably didn't. It probably began on Earth. So that means that at least here, that happened. And we know that the conditions that led to the origin of life on Earth were present on Mars 3.8, 4 billion years ago.

And we know that they're present on Europa today. So I don't see that there's anything special life is just chemistry and it and the the idea that geochemistry becomes biochemistry is not fanciful because it happened here so I think that given the same conditions it would be surprising to me if the same thing didn't happen in that life begins so i i that's one of the to test that is one of the great frontiers of science now it's one of the great challenges which is why another reason we're interested in mars because we know those conditions were there we know there were what's called hydrothermal vent systems on the floors of oceans on mars 3.8 or 4 billion years

ago so it would be good to know if what i've said is right and the way we find out is to find life or evidence of past life are you aware of uh the speculation that was going around how how recent was it that occupy thing the uh the octopus eggs they there was a group of scientists that were speculating that it's you know panspermia the idea of panspermia that it's possible that octopi had come from somewhere else some frozen eggs had actually come from somewhere else and and landed on earth and these are like legitimate scientists they're contemplating not morons i don't think i've seen this the no i didn't but i mean it i think it's unlike so

panspermia doesn't have to be unlikely right i mean for example you might see in the other day we found an earth rock on the moon yes right well he's back on earth now because the polar astronauts brought it back didn't they it's four billion years old or something one of the oldest rocks ever found yeah right so so we know that material gets transferred between planets um and so it's not inconceivable that microbes could survive that journey right we know that microbes can survive in space for example so that isn't mad it's probably unlikely but it's not mad but with the octopus i hadn't heard that but the thing is that the octopus is still extremely similar biologically to us i mean the differences are

negligible yeah so it's still got the same energy system with the single atp and dna and all that stuff it's all very very similar it was something about rna and dna did you find that article i'm trying i'm looking at a different one from a different website it's about the same thing it has to do with the cambrian explosion and there are 33 authors on a paper that got published in The Progress in Biophysics and Molecular Biology that talked about this possibility. There are other people that disagree with it, though. I mean, I suppose I haven't seen it. So I think it's unlikely because the octopus is extremely similar to us.

So that suggests a common origin to me. I suppose the counter argument you could advance would be there's only one way to do life so you could say that actually given because the laws of physics and chemistry are the same everywhere so maybe it's maybe dna with is the only way to do it so that's the way it gets done which is why they're so similar to us although so alien as well yeah they're not though you know that's the thing about an octo that's why i'm surprised about it because they're not though. That's the thing about an octopus. That's why I'm surprised about it because they're not that alien. They're very similar.

Well, in their abilities. I mean, their ability to transform their outer texture and their color almost instantaneously. Oh, yeah. I mean, they have incredible camouflage abilities that really don't exist in the mammalian world. Yeah, but on a cellular level, you look at an octopus cell under a microscope

and you wouldn't be able to tell the difference between an octopus cell and a human cell. So the only way that that would make sense is if all life comes from basically the same kind of building blocks and just varies depending upon the conditions and where it takes place. I'm guessing, but yes, that must be the only way you could sustain that given that they're so similar to us because they really are biochemically is that that's the only way it can be done given the given the building block the toolkit the laws of nature

and the the elements and so on that we have in our universe we have so many different life forms on our planet but if we found anything that's remotely similar to what we have here on earth on another planet it would be such an incredible discovery like if we sat if we found a frog on the moon i mean the world would stop right i'd be very surprised but i mean if we found anything anywhere that is any in any way similar an insect on mars well this is i mean it as i said it'd be micro i think with single-celled things remember i mean you mentioned the cambrian explosion so that is that what we're doing about earth is that although life began let's say 3.8 billion years ago it wasn't until around 600

million years ago or so that or maybe at most 700 that you see any complex multicellular organisms at all so for something like three billion years it was single-celled alone and that's one of the reasons why i would guess if i had to guess i would say that microbes would be common because life began very quickly on earth and i would be surprised to find it on mars but complex life multicellular life insects plants intelligence i would guess will be very rare because it took so long on earth to get there and just slime about three billion years of slime that was it what happened how did it go from slime to giraffes? It did it very quickly once it got going. And it's one of the great unsolved mysteries in biology. One thing that is true is that we seem to be, all complex creatures seem to be, we're called eukaryotes, right?

Which is cells with a cell nucleus and all that kind of stuff. And they look like they're the merger between two simpler life forms, a bacteria and a thing called an archaea, an archaean. So it looks like somewhere in 2 billion years ago, whatever it was in some ocean, the bacteria cell got inside the archaean and survived as a symbiotic organism essentially and then somehow unbelievably managed to reproduce and replicate in that configuration and that does seem to be the origin of all complex multislay life on earth so it's called a fateful encounter hypothesis

and if that's true then it's just a bit of luck and it happened once right and that's why we're here now when you blind look consider like how many billion earth-like planets did you say exist just in our solar system alone in the galaxy 20 billion something like that so one in 10 stars so the odds of complex life out of our incredibly fortunate situation, but the odds of that occurring on any of these billions of other planets that exist? We don't know, but let's say the Earth is, let's say it was on the fortunate side. So we're talking about, give or take, four billion years, right? From the origin of life to now.

And we have a civilization now, and we've had it, our species has been around, what, a quarter of a million years or something so it's just now basically so let's say four billion is on the fortunate side let's say that it was double that or triple that on the average suddenly that's the age of the universe right that's a third of the age of the universe it took so how many of those worlds have been stable for three or four billion years? That's quite a tall order, actually. It looks like our solar system might be quite unusual in that respect. Because the planet's got to remain stable in a stable orbit. The stars got to remain stable.

The large moon helps us. The large moon stabilizes. Jupiter plays a big role. Takes the asteroids. Yeah. Sucks them in. And that, you know, there's a thing, there's a theory called the Grand Tech Theory, which is, so it's very hard to explain the evolution of our solar system. So when you do computer models of solar systems, you don't tend to get four rocky planets to close to the sun

and four big gas giants further out. And one of the current best theories, and I say this because it shows you how lucky we might be, is that Jupiter, they tend to form these big gas giants and migrate inwards towards the star. So in almost all the computer simulations, just because you've got this big gas giant orbiting all the dust around the star, they tend to drop inwards. And it looks like Jupiter did that.

So it looks like it formed and came in and came in almost to where Mars orbits today and then cleared out the region around Mars, actually, which is maybe the reason Mars is so small compared to Venus and Earth. But then Saturn was coming in as well. And in the computer models, the interaction between Jupiter and Saturn stopped Jupiter coming in before it gets to the Earth. And they both get dragged out again to where they are today. Oh, wow. And that seems to be,

it's one of the best theories for the evolution of our solar system. So what are the chances? The chances of that are so minuscule, tiny. So that's the thing, I think, about these rocky planets. In order to get a civilization on them, I think you need, I guess you need quite unusual solar systems. And that would be a guess. And you need quite unusual stability on the planet for billions of years. And that's why I think we might be quite lucky.

And how does Bode's Law work? Bode's Law is a method of detecting, if you look at the mass of a planet, you can accurately detect how much mass and the size of a neighboring planet i think it wasn't just the um the positions of the orbits i think i think right where it is yeah and uh it's one thing that is true about our solar system is that you if you get the computer simulations you can't put more planets in so if you try and put more planets in, it becomes unstable very quickly. So the mass of, like, if you measure Mars, you can accurately depict where the next planet close to it would be? It was. I mean, it was, that's what was done.

Was it 17th century or something? I can't remember. It was a long. Yeah, and it was just one of those things where you notice a pattern. Right. They were just trying to figure out what the patterns were. Yeah, so it's just a pattern, which is um you know not there's nothing to that really um other than to say that most simulations of the solar system if there if you put other planets in they tend to get thrown out by

gravitational interactions so there is a sense in which our solar system has got as much stuff in it as it could have so the planets are nicely spaced and you're right given the mass of them that depends on how close another planet can be before the interaction goes wrong and it gets thrown out into the intergalactic space or something because planets do that you know we we know that planets get thrown out of solar systems by gravitational interactions so yeah so again it points to the fact that solar systems are not are not stable over long periods of time they're not like clockwork things they're not like you know newtonian clockwork and it just goes on forever they're not like that that they evolve and planets can shift orbits and change and one that we know if you look at the surface of the

moon for example it's covered in craters and that was caused they all seem to hit about the same time and it's about 3.8 billion years ago or so and that's called the late heavy bombardment so we know that if you look at cratering rates on mars and on the moon it all seemed to happen in this not all but a big peak around that time. And that seems to be correlated with Neptune moving outwards in the solar system and into Kuiper Belt, basically, or towards the Kuiper Belt and causing all sorts of havoc. And everything comes into the inner solar system. So those things happen. But it didn't happen when life was established on the Earth.

So it's all extremely old stuff that this the shifting takes but but how long is how long has the solar system been in this particularly stable situation that's in now it's it's since about 3.8 billion years ago so if it had been unstable at any point since then then we likely wouldn't be here. Right. Do you think that it's possible, do you ever entertain the idea that it's possible that we are the only intelligent life in the known universe?

I tend to restrict myself to the galaxy. So I do think it's possible that at the moment there's one civilization in the Milky Way and that's us. And I think that's important, actually. And it goes back to what I was saying at the moment there's one civilization in the milky way and that's us and i think that's important actually and it goes back to what i was saying at the start about the astronomy and cosmology being part of the framework within which you have to think

if you're looking for meaning or you're looking for how we should behave even politically you know that has a bearing to me i mean imagine that we're the only place where there is intelligence in this galaxy and how should we behave right should we actually not withstanding the fact that we're tiny and fragile things and insignificant physically should we consider ourselves extremely valuable in that respect? Because there's nowhere else where, you know, I would go as far as to say there would be nowhere else where meaning exists in the Milky Way. Because meaning is one of those things that scientists don't talk about very much. Although Richard Feynman, one of my great heroes, did talk about it. There's a quote where he says, what is the meaning of it all?

It's a great essay called the value of science and so what is self-evidently true is that meaning exists here because it means something to us so that's kind of a an obvious statement your life means something to you and me and so meaning exists but i think it is a local and temporary phenomenon. I think it emerges, meaning emerges from configurations of atoms, which is what we are. We are simply that. We're nothing more than that. We're very, very rare configurations of atoms, I think. And so that means that we are, if you go all the way down that line of logic, we are the only island of meaning in the galaxy.

Meaning only to ourselves. Yeah. It means something to us because we're the only ones who can grasp the concept. And we are finite. We are a finite organism. We have this temporary existence while we're here. And to us, there is meaning. Yeah. And I don't know any other way to define it. Right. and to us, there is meaning. Yeah.

And that's, I don't know any other way to define it. Right. So, I'll define it like that. Yes. I don't think there's global, you know, otherwise you have to believe there's some kind of global meaning and that's a God type thing. And I don't think that's, I think it's more wonderful and more challenging to us because we have to take responsibility for, to say we should operate such that we are it in this galaxy. There's nothing else. I'm sure there are other civilizations out there in the universe, because there are two trillion galaxies.

I just can't believe this hasn't happened in other places. The question is how often does it happen and how widely spaced are the civilizations and i think they're very widely spaced and i think there may be one or two per galaxy on the average i could but that as you said that what you said it beautifully that what what else can we think right and what else do you want i mean i think what it says is you have to take responsibility for all those things as spiritual things that you think about and the emotional things you think about it you you are you are responsible for that you are that right that's whatever that is it exists in you and it will only exist for a short amount of time and so what you know make the best of it would be my view it's so unbelievably compelling though

to consider the idea that somewhere out there there's another civilization that may be even more advanced than us and this this thought of it is just so attractive it's it's it's incredible that there should there should be if If civilizations are common, or even slightly common, then there should be civilizations ahead of us. Yes. Because there's been so much time. But wouldn't you want to see what that's like? Yeah.

It's so compelling. You imagine the time scales. We've been around. As a civilization, let's say 40,000 years. I don't know how long our civilization has been around. Let's say that. The galaxy is pretty much as old as the universe. It's 13 billion years worth of time.

So the idea that there are no civilizations arose, you know, 100 million years ago, 200 million years ago, 1 billion years ago. And imagine what they'd be like if they'd survived i mean we've been we've been around we've had science for let's say since newton or copernicus 500 years at most we've had and look what we've done we've gone beyond the solar system with voyager we've walked on the moon and we're about to go to mars i would think so we're about to begin colonizing our own solar system um so we've done that in 500 years so imagine a million years right in the future so i would it's one of the arguments often used to say there aren't any civilizations out there in the galaxy it's called the fermi paradox because if you imagine a civilization that's a million years ahead of us

they should have written their presence across the sky by now. You should see them. I mean, you'll see us. If we survive a million years into the future, actually even a few thousand years into the future, we will be exploring the galaxy. We will have spacecraft that are going to other stars. We will be doing it.

So our signature will become visible, I'm sure, if we last into the medium term. Would we choose to not do that? Here's my thought on that, is uncontacted tribes. Like, do you know about the gentleman who was the missionary who visited North Sentinel Island and was killed by the natives? North Sentinel Island, which is a really unusual place because they branched off from africa 60 000 years ago and they've been living on this one small island the size of manhattan and as well as we know there's only about 39 of them left somewhere

around there and um we can't we're not supposed to contact them like people are not supposed we're supposed to like leave them alone and there are a rare tribe. When they find them in the Amazon, the uncontacted tribes, our initial instinct is back off, back off, leave them alone, leave them alone. Do you think that perhaps the universe, like if there is a civilization that's a million times more advanced than us, been around here for millions of years of life as opposed to a quarter million, why would they let us know like would they look at us dropping bombs on each other and polluting the ocean and sucking all the fish out and putting clouds into the skies of dirt and particles and why would they look at these crude

monkeys look at that they're so far beyond where they need to be before they could join the galactic civilization network or whatever it is true it's an argument that yeah there is an argument as well that technology so advanced would be difficult for us to detect i mean we tend to think of you know when you say written across the sky i suppose it's true i'm thinking of starships and things like star wars right right big energy things that you can see the signature of. But actually, maybe the civilization just becomes a nano civilization, a tiny little nano. Because that's more efficient.

It's a better way to do things. So it's possible, I suppose, that there are space probes all over the place that are so small and are so efficient and use so little energy that we just don't see them. I suppose that is possible my other thought is that where we are headed it seems to me that there's some sort of a strange symbiosis that's taking place there's a there's a strange connection that we have to electronics and ultimately to an artificial creation artificial intelligence whatever you want to call it, artificial life, something that's created by carbon-based beings, cellular beings that isn't cellular, but also acts like life, that this may be the future of life, that we are so connected to the idea of flesh and blood and bone, but maybe this is just a temporary situation until we transition or if not us transition till it surpasses us and this is the next stage of life but this stage has no need for

all the human and biological reward systems that are in place that made sure that we survive whether it's ego or fear or emotions no need for. That it will just exist and maintain its equilibrium as this new form of life. And that this is the future of life in the universe. And that we'll get there. Maybe it'll only be 100, 200 years from now. But that's what exists all throughout the cosmos. So there's no need to peacock. There's no need to show our signal in the sky and that

it just exists in this form yeah i i agree i wouldn't be surprised either yes that's the that's the counter argument to the this fermi paradox argument that i talked about well exactly as you've just said that basically you evolve to a point very rapidly where you just don't create a signature yes and you don't really get involved as you said maybe it just maintains like it has no yeah well there's no motivation right like it doesn't our motivations are so weird right we have these biological motivations to survive and you know there's motivations to conquer and to innovate and to spread our genes and to move into new territories but if you didn't have biology if you were you existed completely

from man-made materials or from materials found on earth and that this new form of life is created out of that it wouldn't have those unless you programmed them and why would you do that it is interesting isn't it to to because we don't know what consciousness is right right so it's often called the hard problem in science we don't know so it's a good question whether you can build let's say you want to build a self-replicating machine which is what you're talking about and something that can go and maybe go to the moon or mars and replicate itself and then carry on, which is a living thing, I suppose. Yes.

Does it have to have a sufficient level of intelligence that it actually is conscious? And all these things that we talked about, this word meaning that we used earlier that we all understand but can't define. Is that an emergent property that has to emerge if you've got something that's intelligent enough to replicate itself and live and, as you said, be the... I don't know the answer, but it's worth considering that this thing, this emotion, meaning, love and fear and all those things are just the things that happen when you are intelligent right i don't know the answer to that but it could possibly be and does consciousness have to have a a local origin like does it have to come from a thing like if you think about cellular communication the if you send me if you're in england and you send me a video from your phone and it reaches my phone it's getting to me through space it's going through the sky it's like literally from a device not connected by any wires or anything it's coming to me if

if there's a possibility to create some sort of global intelligence through electronics that's non-local. If one piece of it falls off, it just repairs itself or figures itself out. But it's the same consciousness existing on a global scale through some sort of an electronic network that instead of the idea that you and I have that Brian and Joe, you have your mind, I have my mind, and we exist as intelligent beings separate from each other. But instead of that, that all of it is connected and that all of it is something that we can't even conceive of because our brains are too crude, like trying to explain to, you know, Australia Py pithicus what a satellite is yeah yeah i mean yes i mean if you think about our brains um they are ultimately what are they they're just a distributed network of cells connected by neurons and i mean they're very complicated but they are a colony of things that are autonomous in a sense and they're communicating with each other so yeah i don't

i don't see why you can't scale that up in principle i mean i should just the caveat is always that we don't know about this yeah it's it's it's just not understood well i i think there's something weird it's physical though i'm damn sure it's physical i'm damn sure that there's nothing going on in my head other than what is allowed by the laws of nature as we understand them so eliminating who you mean the idea of a soul being some sort of a divine thing that's inside the housing of the body yeah i mean i i would say we can rule that out actually i've argued in the past how do you rule it out i've argued we can rule that out in the following manner so so so here's my arm right so

it's made of electrons and protons and neutrons and if i if i have a soul in there something that we don't understand but it's a different kind of energy or whatever it is that we don't have in physics at the moment it interacts with matter because i'm moving my hand around so whatever it is it's something that interacts very strongly with matter but if you look at the history of particle physics in particular which is the study of matter we spend we've spent decades making high precision measurements of how matter behaves and interacts and we look for example for a fifth force of nature so we know four forces the gravity the two nuclear forces called the weak and strong nuclear forces and electromagnetism and that's what we know exists

and we look for another one with ultra high precision and we don't see any evidence of it so i would claim that we know how matter interacts at these energies so room temperature now these energies we know how matter interacts very precisely and so if you want to suggest there's something else that interacts with matter strongly then i would say that it's ruled out i would go as far as say it is ruled out by experiment or at least this is extremely subtle and you would have to jump through a lot of hoops to come up with a theory of some stuff that we wouldn't have seen when we've observed how matter interacts that is present in our bodies and presumably you believe in the soul you want it to exist outside when you die you still want the thing to be there and you might believe in ghosts and things like that

i mean look at a ghost i mean it's a it is something that carries the imprint of you presumably it looks like you right so that means that it interacts strongly with the matter that is you because it carries a pattern if it carries a pattern it carries information if it carries information there has to be an energy source that allows that information to persist in the pattern to persist and so on so again you end up with a a theory that is postulating something it interacts with light because if you think a ghost is the soul then it's something that people see sometimes so that means it interacts with light but we know how light interacts and we've ruled out anything but the most subtle uh further interaction that we haven't seen so i would i claim and i started off as a joke this actually i wrote it in an infinite monkey cage book this radio show that

i do but it ended up when i'd written it down i thought actually that it makes sense and i read something similar actually i think um sean carroll i don't know if you've had sean yes a couple times he he's said something the same i think in the book that he wrote, The Big Picture, I think he has a similar argument, actually. So, it's occurred to him as well. It's roughly the same argument. So, if you, so, this energy that's interacting with matter, even if you're not moving at all, if you're just thinking, it's interacting with the matter that encompasses your mind or your brain

or your nerves your neurons yeah it's something in there that's interacting with matter whether you like it or not so even just a simple thought process or a dream is still something that's interacting with matter yeah well obviously because it you know you it's your will isn't it in that sense when you move it's presumably right but isn't it, in that sense? Yes. When you move, it's presumably moving. Right. But even if you're not moving, the idea like you're saying your body's interacting with matter as you're moving your arm, but even if you're not moving, if you're just thinking and you're completely still, which is not totally possible because your heart's beating

and you're breathing and all that stuff, but if somehow or another you were able to isolate just the thought, the thoughts themselves are still interacting with matter because they're interacting with the brain itself. Yeah. So there's something in there. Yeah, there's something that interacts with the physical structure of your body. And I would say there isn't. So that's… version is that the brain itself and the body the physicals of this this spiritual self you are uh merely an antenna that's tuning into the the the great consciousness of the universe but why

but then you have to answer what we know what we are made of yeah so we know how those particles behave and interact right so so why do the particles not in any way interact with that stuff because we interact we don't if that's true we don't only just interact with it we interact extremely strongly with it we're interacting with it now yeah every movement i make is the interaction between that every thought you have yeah yes well everything if i move my fingers around everything that i'm doing make is the interaction between that and matter. Right. Every thought you have. Yeah. Yes. Well, everything. If I move my fingers around, everything that I'm doing is an interaction between that stuff and me. So it's a very strong interaction with matter. But we don't see it in all our precision measurements.

The answer for that, the answer is because it's not there. The answer is Jesus, and you can't measure God. That may be an answer. But the point is, as we you can't measure god that may be an answer but the point is as we talked about earlier with absolute space yeah you can't measure it yeah it's not there right it's but for for whatever reason for people there is some incredible motivation to find a divine something or another that's there's something greater than this physical being that there's something what do you think that is like what is that compulsion we we've already sort of talked a bit about it i think it goes to the the heart of this question of what it means to be human so i would say that being human the answer right to the it's not i don't have the answer to the meaning at all but an answer would be

uh we are small finite beings right which are just clusters of atoms as we said before they're very rare but we understand roughly how they how they came to be and we have a limited amount of time not actually unfortunately but because of the laws of nature that the laws of nature forbid us to be immortal they they immortality is ruled out by the laws of physics but also actually what what's interesting about if you look at the basic physics of the universe going from the big bang to where we are today then the physics is driven by the fact that the universe began in an extremely ordered state so it was a very highly ordered system and it is tending towards a more disordered system at the moment and that's called the second law of thermodynamics and it's that basic common

sense thing that things go to shit right so basically it's a second law of thermodynamics what we strongly suspect and i would say no is that in that process of going from order to disorder complexity emerges naturally for a brief period of time so it's a natural part of the evolution of the universe that you get a period in time when there's complexity in the universe so stars and planets and galaxies and life and civilizations but they are they exist because the universe is decaying not in spite of the fact the universe is decaying so our existence in that sort of picture is necessarily finite and necessarily time limited and it is a remarkable thing that that complexity has got so far that there are things in the universe that can think and feel and explore it.

And I think that is the answer. If you want an answer to the meaning of it all, it's that. That you are part of the universe because of the way the laws of nature work. You are allowed to exist, but you're allowed to exist for a temporary or for a small amount of time in a possibly infinite universe. One of the biggest mind-blowing moments I think of my limited comprehension of what it means to be a living being was when I found out that carbon and all the stuff that makes

us has to come out of a dying star. Yeah. the stuff that makes us has to come out of a dying star yeah like that alone that there's this very strange cycle of these enormous fireballs that forge the material that makes brian cox yeah like what that that one alone that there is some strange loop of biological life that comes from stars, which is like the most elemental thing that we can observe. We see these things in the sky. We see the sun in the sky. It's this all-powerful ball of fire,

and that that is where the building blocks for a person come from. I know. And they will be from the carbon atoms in our body. You're right, they all got made in stars. Because there was none of it at the Big Bang. There's only hydrogen and helium. Tiny bit of lithium, to be precise, but nothing else. And so it was all made in stars.

And it's probably from different stars. You know, the atoms in your body, they're not all from one star that cooked it and then died there'll be a mixture of stuff from many stars in your body now and i agree with you that the what more do you want you know when i when i see people go i want more than that i want more you know there must be more to it what do you mean that the we have we have we were the ingredients in our bodies were assembled in the hearts of long dead stars over billions of years and have assembled themselves spontaneously into temporary structures that can think and feel and explore and then those structures will decay away again at some point and in the very far future there'll be no structures left so so there we are we exist in this little window when we can observe this magnificent universe why do you want any more well it's not i think to people well i think a lot of

people aren't aware of all the all the information right and then i think on top of it for some people it's just it's so overwhelming yeah this this concept of 13.8 billion years of everything to get to this point that we're at right now it's so overwhelming that they want to simplify it they want to put it into some sort of a fable structure something where it's something that's very uh common and similar and familiar yeah i i agree um and but i think that's the journey that we go on. The real treasure, I think, is in that journey of trying to face the incomprehensible. Yes. It's in that realization that it's almost impossible to believe that we exist.

That's right. That's a wonderful thing. Yeah. And I think that's what I think you miss out. I think if you decide to simplify it because you don't want to face that, you don't want to face the infinity that's out there in front of us, and you don't want to face those stories, as you said, that you look at your finger

and its ingredients was cooked in multiple stars over billions of years that that's a to me a joyous and powerful thing to think about yes and i think you're missing out if you don't want to face that well i think the distribution of information has changed so radically over the last couple hundred years and particularly over the 20, that you're seeing these trends now where more people are inclined to abandon a lot of the, even if you remain religious or remain, you keep a thought or a belief in a higher power, people are more inclined to entertain these concepts of science and to take in the understanding of what has been observed and documented and written about among scholars and academics.

And there's more people accepting that. If you look at the number of agnostic people now as opposed to 20, 30 years ago, it's rising. It's changing. And I think there's also, because of you and because of Neil deGrasse Tyson and Sean Carroll and all these other people that are public intellectuals that are discussing this kind of stuff, people like myself have a far greater understanding of this than I think people did 30, 40 years ago. And that trend is continuing, continuing i think in a very good direction yeah i mean i don't you know what we should say is that science we don't know all the answers so we don't know where the laws of nature came from we don't know why the universe began in the way that it did if indeed it had a beginning so i don't know why

the big bang was very very highly ordered which is ultimately as sean carroll actually you mentioned him often points out and he's right that the whole difference the only difference between the past and the future the so-called arrow of time is that in the past, the universe was really ordered, and it's getting more disordered. And that necessary state of order at the start of the universe, which is really the reason that we exist, that's the reason, because the universe began in a particular form. We don't know why that was. So we will probably find out at some point, and it'll be something to do with the laws of nature

but so i'm always careful i don't want to science can sometimes sound arrogant right it can sometimes sound like it's the it's the discipline of saying to people well you're not right yes yes and it's not the discipline of saying you're not right it's saying this is what we found out yeah so i i like to say that it provides a framework within which, if you want to philosophize or you want to do theology or you want to ask these deep questions about why we're here, you have to operate within that framework because it's just an observational framework.

So everything we've said is stuff we've discovered. It's not stuff that someone made up. We understand nuclear physics. We can build nuclear reactors for example so we understand the physics of stars so we we understand that the stars built the carbon and oxygen and we know how they did it and we can see it because as i said before we can if you look far out into the universe you're looking way back in time and as you look back time, you see less carbon and less oxygen. So we have a direct observation that in the earliest universe, there wasn't any because we can see it.

And now we see that there is some and we know how it was made. So I think it's important to be humble when you're talking about science. And you're not saying this is the way that it is i mean you are in a sense but you know it's not it's not able to answer ultimate questions at the moment it's not able to answer even whether the universe had a beginning or not we don't even know that and i gave a talk to um i was asked to give a talk to some bishops in the uk about cosmology and i said yeah that'll be great fun and so i went and gave him this talk and and at the end i said i've got some questions so if the universe is eternal and it might be it might not have had a beginning

if it's eternal what place is there for a creator you know that's that's a good question right they didn't they didn't have an answer of course right an eternal creator but yeah but i think that these it might be eternal and we might discover that so we don't know at the moment but we might so i think my point is that these other human uh desires are very natural to religion's a natural thing right people you see all across the world in all different cultures but i think that in the 21st century it religion needs to operate within that framework if it's going if it's going to operate there are still great mysteries and it is appropriate to think about what it means to be human, and I'll give you my view of what it means. But I don't think the problem comes when your theology or your philosophy forces you to deny some facts, some measurement.

These things are measurements. We're not saying, it's not my opinion the universe is 13.8 billion years old. We measured it. It's like having an opinion between the distance from L.A. to Nework now you can't have an opinion on that right we know what it is and it's the same you know it's like you know that these things you know that people say the earth's flat or whatever that so it isn't and we've measured it so it's just stop it you know so but that doesn't mean you can't be spiritual and you can't be religious i would say it doesn't mean you can't believe in god or gods that's not ruled out by science but some stuff's ruled out well i love the way you communicate this

because it takes into consideration human nature and like i love dawkins he's fantastic i think he's very very very valuable but he likes to call people idiots and the problem with that is people go fuck you you're an idiot it like is a natural inclination when you insult people to argue back and to sort of dig their heels in yeah and uh you don't do that and i think that's very important and i think that a guy like dawkins just gets frustrated from all these years of debates with people who are uneducated or saying ridiculous things he's a bit of a curmudgeon you know and he seems to be softening as he's getting older well he's an evolutionary biologist and that's the the front line in some sense isn't it yes it is yeah i mean

the thing about particle physics is that you don't get a lot of shit because people don't understand what you're talking about whereas i think evolutionary biology is right there so i understand his frustration oh i do too having said that you know i've kind of softened a bit over the years actually because now i think at this point both in the us actually and in britain and in some other countries we are at a point you've sort of alluded to it where everybody's angry there's a lot of anger and a lot of it's justified by the way i mean we could talk about that you know income inequality and all those things so there's justified anger but it seems to me that there are people of goodwill who need to band together to diffuse the anger in

our societies otherwise we won't have countries like the united states yes there's united states because it's united and everybody you've got the united the american flag there you know it's a there's a sense of belonging and identity and togetherness in a country which you've got to preserve and so i've stopped actually um picking i used to for example quite enjoy picking fights with deepak chopra on twitter you know and it's just fun it's a laugh you know and you just do it. I've had some fights with him too. He says some crazy stuff.

But I've sort of almost stopped doing it going, well, but relative to some of the other people. Right. He's someone who means well. Yes. I don't agree with virtually anything he says. However, he's a well-meaning person. And so i've started

trying to seek common ground now that's why i i get for example gave a talk to the bishops that asked me to call me i don't agree with them on the framework their theological framework but they mean well most of them yeah so i think seeking consensus and diffusing anger as you said is it is incumbent on all of us especially people like us who have a public voice. We need to diffuse some of this anger because otherwise it will consume everyone. Yes, I've tried very hard to evolve in that respect and just get better at communicating ideas and get better at understanding how people receive those ideas. And I think it's easy to get lazy and to insult and to yeah and sometimes it's fun it's fun yeah well especially me i mean i'm a comedian

it's part of what i do is insult people yeah but i do it for humor i want to entertain people that's the whole idea behind it but i I think in terms of discussing ideas, especially that are so personal to people, like religion, I've reexamined the way I interpret these ideas and the way I talk about these things. It's interesting. I did a BBC program ages ago. I was asked to do it on this thing called the Reith Letters that the BBCbc have

done since 1952 i think it was and robert oppenheimer did them in 53 and it was it's fascinating you can get the transcripts online they're free and you can get one recording of the five they taped over the other four can you believe it wow so you raised them because they wanted to tape something else it's's just unbelievable. But one of them exists of Oppenheimer giving these lectures. Oh, my God. How could they do that? But you can read it. They taped over them.

Can't you buy more tapes? And Bertrand Russell did them. They taped over them. They taped over Bertrand Russell? I know. Oh, my God. It's just bizarre because tape was so expensive. That's crazy.

But it's brilliant. It's called Science and the Common Understanding. And they weren't very well received, because they thought he was going to talk about the Manhattan Project. So they thought he was going to talk about the atom bomb, because he ran it, basically. But he didn't. He talked about how thinking like a scientist,

which means thinking in the way that nature forces you to think, can be valuable in other areas. And that's an insight in itself. The great thing, the unique thing about science is nature forces you to think like that. You can't have an opinion. You can't have an opinion about gravity. You jump out of a building, you're going to hit the ground. That's it. It doesn't matter what your opinion is.

And he said, so if you think about, for example, quantum mechanics, so sometimes you think of a particle like an electron. Sometimes it's a point-like object. It behaves like a little billiard ball thing, a pool ball that bounces around. But sometimes it behaves like an extended thing, like a wavy thing. And nature forces you to hold both ideas in your head at the same time in order to get a complete picture of the object, a description of an electron. And he said that's the valuable thing about quantum mechanics.

You know, unless you're doing electronics or inventing lasers, you don't need to know this stuff. But if you want to learn how to think, it's valuable to be forced to hold different ideas in your head at the same time it's really teaching you not to be an absolutist it's really teaching you the example he uses is because he was i think he was had problems with mccarthy and all those things didn't he so you think he's right in the 50s so he said you can either be you can be a communist which in his definition would be that you think the needs of

the many outweigh the needs of the few right so so society is all that matters or you can be a libertarian right on the far conservative end where you think that the individual is the only thing that matters and that's it but actually of course to have a function in society you need a mixture of the two and we can weight it one way or the other but you need to hold both ideas in your head at the same time and that's he said that's one of the most valuable things about science because it forces you into modes of thought that are valuable and that's what we're talking about here which some absolute positions are always uh just a blinkered sort of subset of what's actually happening you can't understand the world

by being an extremist yeah you've got to hold all these views in your head well that i find that so often on this podcast because i talk with people i agree with and disagree with and i always try to put myself in the head of the person that i disagree with i always try to figure out how they're coming to those conclusions or where they're coming from. And I think it's so important to not be married to ideas. I got in a conversation with someone about this, and they said, sometimes you change your opinions a lot. I go, yeah, I do. I do.

It's a fact. I'm flip-flopping. I'm not a politician like i'm not flip-flopping i'm thinking yeah i'm not sure i'm not sure like i i will have one opinion on a thing whether it's a controversial thing like universal basic income i'll change my mind 100 in two weeks yeah and i'll go no no now i think it's probably a good idea yeah and then i'll go back and forth no no, no, no, now I think it's probably a good idea. And then I'll go back and forth. No, no, no, no, no. People need, it's as cruel as it seems, they need motivation. And I don't know.

I bounce around with these things. But I've tried really hard as I've gotten older to have less absolute opinions. Yeah. Richard Feynman, another great physicist, wrote a similar essay at a similar time to Oppenheimer. And he also had worked on the Manhattan Project and it's called The Value of Science and I think that was 1955 and they both shared actually a

surprise I think that they were still alive because they thought that the power they'd given to the politicians the atom bomb would destroy everything they didn't think the political system would control it and it did so that's an absolutely remarkable thing yeah we're still here but in in that essay he said that um the the the most valuable thing about science is the realization that we don't know and he said he said in that statement he calls science a satisfactory philosophy of ignorance by the way he said in that statement is the open door the open channel he called it so if we want to make progress we have to understand that we don't know everything and we have to leave things to future generations and we can be uncertain and we can change our

minds and he said that that's that it's a great last line i can't remember exactly what he says but he said it's something like it's our duty as scientists to communicate the value of uncertainty and the value of freedom of thought to all future generations that's the point that's what freedom of thought means freedom of thought means the freedom to change your mind in fact said that's what democracy is if you think about it democracy is a trial and error system so it's the it's the admission that we don't know how to do it therefore we'll change every four years we'll change the it's the admission that we don't know how to do it therefore we'll change every four years we'll change the president or every eight years we'll change the president why because the president doesn't know how to do it so someone better there will be someone better

that comes along and then someone worse and someone better but it's a trial and error system and he's right and he's right that that is the open door that's that that's the road to progress it's certainly better than humility yeah one of the things that i love so much about bertrand russell and about feinman was how human they were they were very human i mean feinman liked to play the bongos and he's chasing girls and bertrand russell was addicted to tobacco he would talk about how he wouldn't fly unless he could smoke like he had to get us was back when they had smoking sections on airplanes and he had his pipe and he just refused to fly without tobacco he couldn't imagine being without tobacco i'm like that's so strange for such a brilliant

guy to be addicted to such a gross thing yeah you're right because i think these these are people that found existence joyous right they wanted to know they just wanted to know stuff yeah they didn't want to know everything because you can't know everything right um you know i suppose that's what if you think about what the job of the scientist is it's to it's to stand on the edge of the known because you're a research scientist so if there's nothing to know then you've got no job right so you have to be naturally comfortable with not knowing and i if there's one thing i really do think we was how do we begin to patch our countries back up again one of the reasons i think in

education is to teach people the value of uncertainty of not knowing it is not weak right to not know it's actually natural not to know and that's one of the problems with religion is to say that you know when you do not or to say that you have absolute truth and absolute knowledge of something yeah when it can't really exist yeah i mean history tells us doesn't it that you know anyone who thinks they've got absolute knowledge causes trouble. Yeah. Did you see Ex Machina? Yeah. Did you enjoy it?

Yes. Yes, I know Alex Sculland because he wrote Sunshine. Oh, right. That's right. And 28 Days Later. Yeah. And that other new movie, the weird one, the alien movie, he wrote that as well, right?

Annihilation. Annihilation, yes. It's a great soundtrack. Yeah, yeah Yeah Are you scared Of artificial life Artificial intelligence Elon Musk Scared the shit out of me

Yeah When he talked about it Like he He talks about it like We're in The opening scene Of a science fiction movie Where he's trying to warn people

And then They don't listen to To the genius And it goes south sort of depends i chaired a debate on this um for the royal society in london a few weeks ago and uh the so it's true now at the moment what what people tend to be frightened of are general ais or agi they call it general intelligence, which is like what we talked about earlier, a human-like capability thing. And we're miles away from that. We don't know how to do it. We haven't got them, and we're miles away.

So at the moment, artificial intelligence is expert systems and very focused systems that do particular things. You can be scared of them in a limited economic sense because they're going to displace people's jobs. And actually, interestingly, in this panel discussion we had, it's going to be what you might call middle class jobs in the UK. So white collar jobs. Which is why people are interested in universal basic income to sort of replace money that's going to be lost because there will be no jobs for all these people. Otherwise, we have just a mass catastrophe.

Yeah, they're very good. There will be no jobs for all these people. Otherwise, we have just a mass catastrophe. Yeah, they're very good. Someone said that these systems, artificial intelligence systems, at the moment, they're very good at doing things like lawyers work. So they're very good at reading contracts and things like that. It's interesting because it's a revolution. It's not like the Industrial Revolution where it's manual labor that gets hit necessarily.

This is kind of interesting because it hits that kind of intermediate level that usually escapes um so you're right one of the answers is to tax there was an example was a robot tax so in a car factory you say to the manufacturer well okay you can have a robot well you pay the robot the same as you pay a person and then that money goes into funding universal basic income or something like that so i think there's got to be an economic change because these systems will be there but all the experts i spoke to agreed that the idea of a terminator style general intelligence taken over the world is miles away and um so whilst we might start thinking about the regulation it's not not going to happen soon, is the general point, I think. So I would disagree with him on that. I think it's too far in the future at the moment.

I might be one of those people that's going, eh, it's going to be all right. And then, you know, my iPhone takes me out on the way to the airport. That's the thing. I mean, it's our choice at the moment isn't it i mean don't don't give your iphone a laser for example and it doesn't matter if it goes crazy and tries to take over the world i know i know that's a bit facetious because they can he would say they could take other power grids and all that kind of stuff yeah i guess but well it's these

concepts that are really hard to visualize like sort sort of Kurzweil's idea of the exponential increase of technology leading us to a point in the near future where you're going to be able to download your consciousness into a computer. You talk to computer experts, they're like, there's no way, we're miles away from that. Or neuroscientists. Yeah. Neuroscientists go, no way. One brain cell probably we can't. one brain cell probably we can't but kurzweil's convinced that what's going to happen is that as technology increases it increases in this wildly exponential way where we really can't visualize it we can't even imagine how much advancement will take place over 50 years but in those 50

years something's going to happen that radically changes our idea of what's possible and i think elon shares this idea as well that it's going to sneak up on us so quickly that when it does go live it'll be too late yeah i mean it's worth putting the the framework in place i think the regulatory framework even as you said for the more realistic problem which is people's jobs are going to get displaced yes and there's a great um I was at a thing and someone said, I can't remember who it was, but they said that the job, it was a politician, that the job of the innovation system is to create jobs faster than it destroys them. So you've always got to remember that as a government and as regulators.

If you're going to allow technologies into the marketplace that destroy people's jobs, it is your responsibility to find a way of replacing those jobs or compensating those people as you said otherwise you get breakdowns so being a human being those that people need some meaning like they just giving them income i think is just going to i mean it's just my speculation but it's going to mass despair. Even if you provide them with food and shelter, people need things to do. So there's going to be some sort of a demand to find meaning for people, give them occupations, give them something, some task. It seems to be one of the critical parts of being a person is that we need things to do that we find meaning in

you know like you were talking about we're the only things that we know of that have meaning that find meaning and share meaning and believe in that we're gonna need something like that if universal basic income comes along i don't think it's going to be enough to just feed people and house them they're gonna want something to do if a you know a person is a you're doing something for an occupation and this is your identity and then all of a sudden that occupation becomes irrelevant because the computer does it faster cheaper quicker these people are going to have this incredible feeling of despair and just not being valuable yeah i mean what won the the utopian sort of version of this is that everybody gets to do what we're doing now,

which is make a living sort of thinking and creating. So that's the utopian ideal, is you don't need to do the stuff, the job that you don't really want to do in the factory. Right. You can do the thing that humans are best at. But I agree, that's a very utopian view yeah does everybody want to do that or does everybody have the mindset well because

education if everybody had an interest like that if everybody went on to make pottery and painting and doing all these different things they've always really wanted to do and their needs are met by you know the universal basic income money that they receive every month but boy there's a lot of people i don't think have those desires or needs and to sort of force it onto them at age 55 or whatever it's going to be yeah it seems to be very very difficult yeah yeah i agree yeah it's a big challenge but i think that in concept at least it's inevitable that we do have some sort of an artificial intelligence that resembles us or that resembles something like ex machina if people choose to create that i mean choose to create

it in our own image but that's very godlike isn't it god created us in our own image, but that's very God-like, isn't it? God created us in his own image. Yeah. And again, yeah, I don't know. When I talk to people in the field, as you probably have, most of them say, don't know how to do it. Yeah. It's really, it's going to be miles away. So maybe I'm hiding my head in the sand a bit, but I don't think so. away so maybe i'm hiding my head in the sand a bit but i i don't think so i think it's i think we'll know it when i don't think anyone's going to do it accidentally right so i i don't

think it's just suddenly going to be upon us i i i think we will see we'll we'll see ourselves getting acquiring that capability we'll see ourselves getting close we'll see those systems beginning to emerge, and then we'll think about it, I think. 200 years ago, if you wanted a photograph of something, you want a picture of something, you had to draw it. I mean, there was no photography 200 years ago. Yeah.

I mean, just think of that. It's almost inconceivable. No automobiles, no photography. What was automobile? Maybe there was some sort of machines that drove people around, right? Something close. There was trains earlier than that, right? You go back 500 years, you have almost nothing.

It's crazy. Oh, we've been quick. It's so fast. It's so fast. I mean, and then this, what we're doing right now, there's people right now in their car that are streaming this. So they're in their car and they're listening as they're driving on the road. Maybe they have a Tesla. Maybe they have an electric car.

They're driving down the road, streaming two people talking, where it's ones and zeros that are broken down into some audible form, and you can listen to it in your car. That is bananas. Yeah. I agree. We've been quick. So quick.

Well, think of the world, you know, the internet. I mean, it's not long. I mean, I remember it being invented. Yeah. Well, certainly the web. When did you get on? So the web, well, it was very early for me because I was doing particle physics.

And, of course, the web comes from CERN, the WWW bit. Right. So certainly in the early 90s, I was involved in that, you know, in the university environment with email and all that kind of stuff. So I don't know when it kind of didn't really – you could have a web browser that just – the only sites that were there were NASA. And I think NASA had one of the early sites and CERN. And there's very little else.

When did you become involved with CERN? So that would be, I started doing particle physics in 95. And when did the Large Hadron Collider go live? That was, I remember it was 2007, I think i think it was or 2008 it's so long ago i can't remember it's about 10 years ago but it started up it started up and then we had a problem with it and then it took a bit a while to fix um so it hasn't been taking data that long but it's a tremendously successful thing now and it's it's operating beyond its design capabilities it's quite incredible it's so stunning like as a physical thing that this i mean how large is it

how large is it it's 27 kilometers so what's that about 16 miles 16 miles and it's a circular yeah sort of a building yeah well it's a big tube i mean you think basically it's mainly under france and partly under switzerland and it accelerates protons around in a circle both ways they're one one beam goes one way one goes the other way and they go around 11 000 times a second so that's a very close to speed of light 99.999999 percent the speed of light and then we cross the beams and collide the particles and in those collisions you're recreating the conditions that were present are less than a billionth of a second after the big bang so we we know that physics so going back where you said about the carbon and the oxygen we can trace that story back way beyond the

time when there were protons and neutrons to when there were quarks and gluons around and and go all the way back and the higgs boson doing its thing back then. And so we can see all that physics in the lab. So that's why we have a lot of confidence in that story. It's so fascinating that they were able to talk someone into funding that, that they got a bunch of people together and that you were able to explain to politicians and, you know, regular people what you're trying to do. It's a great example of how you get something done.

So it was the 50s when CERN was established. I think it was 53 or 54. I can't quite remember. It's something like that. And it was built out from the Second World War. So you have Europe at the end of the war. And it was realized that the only way forward for Europe was collaboration, to rebuild the scientific base for peace, for peaceful purposes.

And so CERN was set up as an international collaboration in Europe initially with that political ideal that it was it was explore nature uh just for for freely and for peace for peaceful means peaceful reasons and so that was uh the politics was right so it was set up by international treaty so that the member states are bound together by a treaty and they pay a small amount relatively small amount each into CERN every year which is a percentage of their GDP and that's the money they use to build the experiments and build the accelerators so it's very hard to get out of it and you wouldn't really want to because it's a small amount of money per country and CERN doesn't

get extra money to build things it just takes its money and basically saves up and plans itself but because it's got a regular stream of money it can do it so you can say we're going to build this machine and it will take eight years because that's how much money we've got and we'll build it in eight years and we know how much money we've got so we can do it and it's a lesson I mean that the reason that the u.s collider the ssc failed is because it's the problem you have in the u.s with the funding system as you've seen in the last few weeks yeah is that it's very arbitrary and it's open to political maneuvering and things can be shut down and take and cern is not like that cern has got a guaranteed stream of funding small

from each country. And so you can do these projects. And the one in the U.S., that was during the Clinton administration? Is that what it was? Yeah, it was closed. Was it Clinton? It was closed down by Congress on a very slim vote. And it was in Texas. So it was one of those things where you've got states vying for money.

And it was half built. And everyone was there. And the thing, it was bigger than the LHC, and it was closed down. So you waste a lot of money. Is that a huge disappointment for the scientific community? Were people very hopeful that this was going to go live? Yeah, it was being built, so it dug half the tunnel. What would it be able to do that the LHC couldn't do? It was a higher energy accelerator than the LHC.

So it would have discovered the Higgs particle first, had it been running. But the half-built part, is it useless now? Or can they sort of recharge it up again? No, I think they filled it in. I think so. I mean, it was just half a tunnel, you know. So that's the thing. You can do these wonderful things for not a lot of money if you

just do it over many years and have stable funding yeah just commit to doing it the filling it in part is like and you look at cern as well and people you know people ask me now i think the uk pays about it's about 100 million dollars a year that's what the uk pays in and it's about same for germany same for france and so on and some people say what do we get for that i mean first of all it's not the whole budget of cern is about the same as a budget of a medium-sized university so it's not a lot it's about a billion dollars a year or something which is what a university has so it's not a lot in the scheme of things and what's it done though well we invented the

world wide web as we've just said a lot of the medical imaging technology that we use comes from cern it's pioneered the use of these very high field magnets which is what it needed so it's engineering at the edge and engineering at the edge generates spinoffs and expertise to get used in other fields so there's cancer treatment so-called hadron beam therapy so if you've got a brain tumor now it's quite likely that you'll have one of these targeted particle beam therapies which is like very highly targeted sort of chemotherapy it's not chemotherapy it's just radiation that you can target in a beam into your head and attack the tumor and those those are particle accelerators so most particle accelerators today are in hospitals and in medicine but they came from doing particle physics that so the the

spin-offs of these big experiments at the edge of our capability are always immense which is why they're worth funding at these very low levels. But it's not just the knowledge. It's the engineering expertise. There is a practical application for everyday life. There always is. It's just finding out how to do hard things is usually useful is the moral. And it wasn't just the Higgs boson particle that you guys had discovered. What is quark-gluon plasma?

Yeah, so that's shortly after the billionth of a second after the big bang yeah you end up with a soup of um quarks and gluons so quarks are the building blocks of protons and neutrons and gluons are the things that stick them together um so a proton has two up quarks and a down quark and a neutron has two down quarks and up quark and so on so they're the constituents the protons and neutrons which are the constituents of our atomic nuclei um so if you go if you go to very high temperatures or high energies then the protons and neutrons fall to bits then you end up with a soup of quarks and gluons and that's a quark gluon plasma and it's insanely dense right yeah well Yeah, well, very high energy.

So you get that. So we've been exploring that. We don't only collide protons together. We can collide lead nuclei together or silver nuclei together at the LHC. And that's when you make these kind of soups of nuclear matter, if you like, very hot nuclear matter to explore that physics to that nuclear physics wow and i was reading something about the the weight of of that stuff that like a sugar cube like what what is the what is the actual weight well it depends how dense it is that's i don't there i mean there the thing i remember is the sugar cube of a neutron star material which is i don't know. I mean, the thing I remember is the sugar cube of a neutron star material,

which is, I don't know how many hundred million tons. I can't remember. You know, it depends. So I don't know with the quark-gluon plasma. I don't know what number you're... There was something. There was one of the things after the discovery, they were talking about the massive weight of quark-gluon plasma.

And they're like almost incomprehensible. Yeah, I don't know the number. But something crazy. Now, once these... You got something? Oh, here it is. 40 billion. Oh my god, a cubic centimeter would weigh 40 billion tons.

Oh. Good lord. I didn't know that. I david i know david actually yeah the dentist matter created in the big bang machine and what are they doing right now it's um closed for engineering and upgrades upgrades yeah i mean one thing we're trying to do is one of the things in particle physics is that you want as many collisions per second as you can generate and then we have a collision we have a what's called a bunch crossing lhc

we can vary it but it's something like 25 nanoseconds depending on what so it's really we get a lot of collisions per second and the more collisions per second you can get the more chance you have of making interesting things like Higgs particles or whatever else may be out there waiting to be discovered. I mean, it's possible there are other particles out there that we haven't yet discovered that could be within the reach of the LHC. And if this one that was in Texas had gotten built and it was more powerful than the LHC, you'd have even more opportunity to do something like that. Yeah. powerful than the LHC, you'd have even more opportunity to do something like that. Yeah.

Now, when these things are created by these collisions, how long do they last? Oh, fractions of a second. So the general rule in physics, in particle physics, is that the more massive it is and the more things it can decay into, the faster it will do that. So basically, the heavy things decay into light things and so the only the stable particles are things like electrons um and some of the quarks and the up quarks and down quarks are stable things but uh so so everything tends to decay very fast so we're talking fraction billions of a second fractions. And how are they... Less than that. How are they registering its existence? Like what is being used to measure it?

So what you see, if you collide... At the IC, we collide protons together. And protons have got loads of stuff in them, loads of gluons and the quarks. So you get a big mess, first of all. So most of it's a load of particles that are spraying out which you're not interested in but sometimes when you when let's say a couple of the glue-ons bang

together and they can make something interesting like a top quark or a higgs particle what's a top quark a top quark is a very heavy there's six quarks so there's up and down charm and strange bottom and top charm and strange yeah so and top. Charm and strange? Yeah. So strange was literally in the, what was it, the 50s when we discovered them. Someone said that's really strange. So it's a strange and new kind of particle. So, yes, we have six quarks.

They're in three families. So the up and down are one family. And then the charm and strange are another family in the top and bottom are the third family. family and then the charm and stranger another family in the top and bottom of the third family and so we for some reason so the only thing the only particles we need to make up you and me are up quarks down quarks and electrons but for some reason there are two further copies of those which are identical in every way except they're heavier so there's the charm and the strange quark and a heavy electron called a muon and then there's the top and the bottom quark and a heavy electron called a muon and then there's a the top and the bottom quark and another heavy electron called the tau and that's it so that there's this weird pattern

that we don't understand so we don't seems like you only needed the the first family to build a universe right right but for some reason there are two copies now and the heavy ones decay into the lighter ones is the point so when you make them they're not around very long and just to answer your question what happens is that when they decay they throw their decay products out into our detector so we take a photograph of the cascade of particles that comes from these heavier particles decaying and the trick is to patch it all up to see to try and sort of work out what everything came from wow now when they five find these unexpected particles then what happens then

there's the study of them then there's the then everybody gets together and go okay what the hell is that yeah what is that what do we do so we want to know with a higgs particle we know what it does which is it gives mass to everything so it's fundamentally the thing that gives mass to all the other things in the universe at the most fundamental level so so electrons for example and the up and down quarks they get their mass from their interaction with the higgs that's why they're massive that's another reason we exist you know we go right back we wouldn't exist if there wasn't mass in the universe and the higgs is ultimately responsible for that mass um i keep saying i keep caveating it because then you get other sorts of mass that

are generated but but that the fundamental basic seed as it were is from is from the higgs um so what we want to know is we want to know how that thing behaves and the way so you want to study it so you want to make a lot of them so you can take a lot of pictures of it and study it a lot and see exactly how it does that and so that's what we're doing that's what we're engaged in at the moment we're making high precision measurements of the way that particle behaves so we can understand the laws of nature i mean that that is the laws of nature how are those particles behaving and what are they doing but it is possible that some new form of some new form of particle something else could be discovered

yeah that we don't know about yet because we know almost know that there are other particles out there in the universe we almost know so the thing called dark matter yes so we look into the universe and we see that there's a lot of stuff there that's interacting gravitationally but is not interacting strongly with the matter out of which we are made and the stars are made so it it's almost certain that that's some form of particle that that fits beautifully and we see lots of different observations the way galaxies rotate and interact and even the oldest light in the universe the so-called cosmic microwave background radiation we see the signature of that stuff in that light as well so we think that there's some other particle out there and and to

be honest we thought we would have detected it i think at lhc we have lots of theories called super symmetric theories that make predictions for all sorts of different particles that would interact weakly with normal matter and i yeah i think it's broadly seen as a surprise that we haven't seen them at lhc so that just may well mean that either they're very they're a bit too massive so we need more energy to make them and we just haven't quite got enough or we're not making enough of them often enough to see them which is one of the reasons we're upgrading the lhc so we also look for them by the way um directly so we have experiments under mountains we bury them under mountains so the cosmic rays

from space don't interfere with them and we're looking for the rare occasions when these dark matter particles bump into the particles of matter in the detector so it's a because the idea would be this room's full of them i mean the galaxy is swimming with dark matter as far as we can tell but it interacts very weakly with this matter so it doesn't bump into us very often so we're looking for the direct detection of it and we're looking to make those particles at lhc so it's everywhere but it doesn't interact with us very weakly um so interacts through gravity and the the the archetypal particle that's everywhere that doesn't interact strongly is a neutrino.

So we do know about neutrinos. We've detected those. And there are something like 60 billion per centimeter squared per second passing through your head now from the sun. So they get made in nuclear reactions in the sun. But they go straight through your head and then actually straight through the earth, pretty much. Occasionally, one of them bumps into something and we can detect those because there are so many of them uh going through but we only detect you know i don't know one or two a day and the idea is that dark matter encompasses an enormous percentage of the universe yes it's five times as much matter as dark matter than is normal matter

and the number is 25 of the universe so roughly speaking about five percent of the universe is normal matter stars and gas 25 is dark matter yeah so about yeah five's normal about 25 is dark matter and about 70 is dark energy that's the other thing the other thing about yeah yeah so what the hell's that don't know know what it does so again see if we got we talked about einstein's theory earlier so einstein's theory which works spectacularly well says that if you put stuff into the universe we said before then it warps and deforms and stretches and it very precisely tells you given the stuff that you put in it how much does it stretch and how does it stretch and the the measurement we have is how it's stretching so so we we observe

the thing we observe is how the universe is expanding and how that expansion rate is changing and how it's how it's changed over time so we have very precise measurements of that so then we can use the theory to tell us what's in it given that we know what how it's responding to that stuff and that's how we discover dark energy so we notice that the universe's expansion rate is increasing so the universe is accelerating in its expansion which is exactly the opposite of what we thought now this is in the 1990s that we discovered that so we can work out what sort of stuff and how much of that stuff you need to put in the universe to make that happen and that's where we get these numbers from um was there a resistance to that when that was first

proposed yeah i remember my one of my friends at brian schmidt got the nobel prize for that and then i remember i talked to him and he said he was a postdoc i think at the time so a young researcher and he made he's making measurements of supernova the light from supernova explosions which are so bright that you can see them you know hundreds of millions billions of light years away and he noticed that if you look at the data the light is stretched in the wrong way so we look at the stretch of light as it travels across the universe and the universe is expanding it stretches the light so it changes the color and he noticed that there was a discrepancy which which said that the universe that the expansion rate is speeding up. It's been speeding up for, I think, something like 7 billion years or so.

It's been speeding up. So he thought that he's done something wrong. So he checked it and checked it and checked it, and he couldn't find anything wrong. So he did what a good scientist does, which is he published it so that somebody else could find out what he'd done wrong. And he said that he thought it would be the end of his career he thought he'd be a life in stock you know and he got the nobel prize because he was right it is stretching wow it's a great lesson means that

if you if you're sure that you can't see what you've done wrong then you publish it because that's that thing about humility we talked about earlier you know what we ultimately we're not trying to be right we're trying to find out stuff and so a good scientist will be really happy if they turn out to be wrong because they've learned something now that's the that's the it's good that he took that path because he got the nobel prize now when he received the nobel prize and this concept started being uh discussed what was the initial reaction to it well it's it's interesting because it's allowed in einstein's theory and it was in einstein's original theory so it's called it's got a name it's called the cosmological constant and that's um it's just allowed in the equations and einstein

actually introduced it um initially to because einstein's's equations strongly suggest that the universe is expanding or contracting and not just sat there. So even before we'd observed anything, Einstein had a theory that suggested that the universe is just not static. And actually, it really strongly suggests that there's a beginning. So the theory itself, on its own, own suggests that you can see that if the universe is stretching today then it must have been smaller in the past right everything must have been closer together let's say that um so the um there's a man actually called george lametra who was uh who

worked independently of einstein but the same time in the early 1920s before we even knew there were other galaxies beyond the milky way and they noticed that the equation suggests the universe might be stretching. And so he wrote to Einstein and said, your theory suggests there was a day without a yesterday. Because he thought if everything's expanding now, then it must have been closer together in the past. And so there might be a time when it was all together. And he was a priest.

Wow. So he's a Belgian priest. So I think, I mean, I wrote about this. It's kind of my interpretation of it. But I think that he was more predisposed to accept what the equations were telling him because a beginning, an origin for a priest is really a nice thing

because it tells you there's a creation event. And Einstein tried to dodge it and put this allowed term into his equation which is the almost the stretchy term to say well if it's all if it's all kind of contracting or something can i put something in to make it stretch a bit to balance it all out so it can be eternal so and you can't you can't make it eternal that way but he so he tried it then he took it out and called it his biggest blunder taking it out was his biggest wonder no you call putting it in his biggest blunder or at least some people think what he'd done was miss the prediction of the big bang really so by trying to fiddle around to have a static universe that's stable he missed what the

equations were screaming his own theory was screaming to him which is that no the universe expands or contracts and he missed it right so i think that's probably what he meant by biggest blunder but in any case he took it out and then later in the 1990s it turns out that no it's there but it's really small it's tiny tiny effect but it's still dominating the universe now and it will and it will dominate even more in the future so we think that we're in a universe that will continue to expand essentially doubling in size on a fixed time scale which which is about 20 billion years. So within every 20 billion years into the future, forever, unless something happens,

the universe will continue to expand and double in size. Two years. And that's the dark energy that's driving that. But nobody knows what it is. It's one of the cutting-edge edge massive problems in theoretical physics and what is being done to try to get a better grasp of what it is i mean it's theoretical i mean we're making very precise observations of it right but it looks like this constant so it looks like it's basically one a number if you like in einstein's equations and just really simple so it looks like it's something that may be a property of space itself don't know but it looks like a very simple thing that doesn't

change over time and just stays there so so it requires theoretical advance as well and so people are trying very hard to do that it's so crazy when you go from galileo to modern theoretical physics that they're still in the midst of this understanding yeah of what all this stuff is yeah i mean these are you know these are fundamental and difficult problems and we're talking about the origin and evolution of the universe right that's what cosmology is and it's also particle physics i mean the way that these things this stuff we keep talking about the stuff in the universe that's what the lhc studies it studies how the stuff behaves um right now these are it's very theoretical right they're trying to wrap their their minds around what this is and what the properties of it are. Do you envision a time where you can actually physically measure this

and have a real clear understanding of what it is and what its properties are? The dark energy. I don't know. I mean, for example, there are theories, for example, which are probably not right, but they're not necessarily wrong either. There are theories that try to link it to the higgs particle so the higgs particle which we've discovered and can measure has some properties that we think the dark energy would need and also this inflation that i mentioned way back at the start of the universe it has some of the properties that can

do that as well so for example there are people who try to link them so we do have an observation of the higgs we can study that so are they linked don't know um but so it could be that we can study it even though it's a very small weak effect and it could be web direct access so this is is great. I mean, these are big mysteries. There's something really profound we don't understand about the way that stuff, in particular the Higgs, actually interacts with space and time. So very naively, the Higgs should blow the universe apart. Just very naively.

It's loads of energy in a very small amount of space huge amounts of energy in the higgs field but it doesn't do anything apart from give mass to things it doesn't seem to it doesn't directly affect space but everything else that you put in space directly affects it so you know there are there are kind of issues there that we don't and it just says we don't get it we don't we don't get it yet it's just another one of those they probably late that i if i was to guess i'd say there's some link there you know there's something going on and solving one of them might solve the other two inflation higgs, something. How many people worldwide would you estimate are trying to grasp this and working on this?

It's a good question. I don't know. I mean, it's probably tens of thousands. It's tens of thousands if you count all the people who work at CERN and the particle physicists and the theoretical physicists. It'd be tens of thousands. Because it's so important for us to get an understanding of what's going on, but yet so outside of the grasp of most people, including me. Like, I'm listening to you talk about this, and I'm like,

thank God there's people like you. Like, whatever. Thank quarks. There's people like you out there that are doing this. But it's almost like you're speaking another language. It's so strange to me. Well, it's very new stuff. Yes.

You know, I mean, even when I was at school, so when I was at university, we hadn't discovered the top quark. We sort of knew it was there. We thought the Higgs might be there, but we had no idea whether it was, you know. So we're moving. In my career, we're moving quite fast. And you're right. These are the most fundamental questions about why is the universe the way it is,

and even possibly why is there a universe, right? But we're away from that yet. But if we're ever going to answer that it will be by doing stuff like this and this is all addressed in this live show that you're doing this worldwide live show and certainly the the also the consequences of the not the consequences of knowledge but the the cosmology is terrifying as we've started with. So I think, as we've said, it raises questions. It makes quite vivid questions that we all have about, you know,

what are we doing here? So I try, and I think this goes all the way back to me really being into Carl Sagan. He always used to try this you try to link it to things that people think about naturally and that's why people are fascinated by this stuff because they do actually think about it you might not be with the right names or the right words or the right facts even but they're thinking about how did i get here how did i come to exist? What is the future? Do we have a future?

What was our past? You know, these are universal questions, I think. Yeah, they certainly are. And the way you're doing this with your live show, you were saying that you have an enormous visual aspect to it as well. We have the biggest screen we can get in every venue. And it's LED. It's one of the state-of-the-art modern LED screens.

So they're like Lego. And you can build them. So you fill the venue with it. So, you know, Wembley Arena, then it's 30 meters wide or whatever. By 8 meters high. It's enormous. You must have a huge crew carrying all this stuff around. Yeah, that's like 16 or 18 people.

And it's like a rock and roll show. And some of the venues we're doing it in Northica that in canada they're a bit smaller venues but we just fill it with screen as much as we can get and then the graphics a lot of the graphics i i have were done by a d neg who did x machina actually and interstellar and the reason i i mean i chose i said chose them i rang them up and goes please please will you do this and they, how much money have you got? And, you know, because it's way lower than Chris Nolan. And they did it. They just like the idea of these messages and these ideas.

So they use the software that they use for Interstellar to create images of black holes. Wow. And they use general relativity. They coded it into their graphic software software so they can ray trace lights around black holes and you can move the camera around the black hole and it traces the way all the light moves around it so if you remember those amazing get the gargantua the black hole interstellar that's that's a simulation it's not an artist's impression it's a simulation of what einstein's theory tells us a black hole will look like and so i can use that to talk about what happens when you fall into a black hole what

would you see watching someone fall in and you can explain all that using einstein's theory you know the idea that it's kind of a well-known idea it's a bizarre idea that if if i was to fall into a black hole and you were watching you'd'd never see me fall in. You'd see time slow down, my time slow down as you watch me. So in the end, I'd just slow down and slow down and slow down. And then I'd get frozen on the event horizon and just fade away as an image, a reddening image on the event horizon. So time passes at different rates as you move close to the black hole and far away. Because space and time are distorted by move close to the black hole and far away because space and time are distorted by the mass of the black hole and so i can i talk about all that but i talk

about all that with this incredible image which we had it's so high resolution by the way that it was higher resolution than they used for interstellar because my screen's so big. So we need a special machine to play it. You can buy the most expensive Mac Pro in the world and it will not play this stuff. So I love that from a geek perspective. It's brilliant. You have to have a special video player to play the damn thing.

So it's just like a series of CPUs all attached together in some sort of a supercomputer? Yeah, it's one of those big visualization graphics things. But these files are like 20 gig video files. Wow. Because there's so many pixels. The pixel resolution is really geeky, isn't it? The pixel resolution is 6400 by 1536.

Is that impressive, Jamie? It's like 16K, right? It's a lot. Something like that. Yeah, it's big. Yeah, it's really big. It's a lot. They're huge files are

you coming to los angeles with this yeah when i've hit the montalban theater in may the end of may i'm there if i'm here well there it all is oh yeah no you gotta come 24th of may oh you're in san diego as well i gotta see one of these i gotta go to one of these it's gonna be great fun and however much stuff we can fit into those pictures you too you handsome devil look at that nice jacket on looking good so yeah someone gave me that actually i managed to scrounge that but it's cool because you look like a cool guy like you're a cool guy with space behind you wow that's awesome man well listen thank you so much for doing this i really appreciate you i appreciate everything you're doing it's awesome oh thank you i always enjoy i loved it last time and people still talk about it when i was on last

time more people ask me about meeting you than virtually anybody else honestly get ready because it's like a hundred times more popular than it was back then it's going to be very strange now but thank you again i really appreciate it i can't wait to see your show thank you so much thank you thank you bye everybody again. Really appreciate it. I can't wait to see your show. Thank you so much. Thank you. Bye, everybody.