The Infinite Monkey Cage - Making the Invisible Visible

Episode Date: February 13, 2017

Making the Invisible, Visible Brian Cox and Robin Ince are joined by comedian Katy Brand, Cosmologist Prof Carlos Frenk, and biologist Prof Matthew Cobb to discover how to make the seemingly invisible, visible. They look at how the history and development of the telescope and the microscope have allowed us to look at the impossibly big to the seemingly impossibly small, to gain insight into the history of our universe and the inner workings of the human body. They look at how radio and space telescopes have allowed us to look back in time and "see" the big bang, and understand the age and content of the early universe, and how space telescopes have thrown light on the mysterious substance known as dark matter. They also look at the way microscopes and new biological techniques have allowed us to understand the seemingly invisible processes going on inside our cells. They also ask what, if anything, will always remain invisible to us - are there some processes or concepts that are impossible for us to "see". Producer: Alexandra Feachem.

In our new podcast, Nature Answers, rural stories from a changing planet, we are traveling with you to Uganda and Ghana to meet the people on the front lines of climate change. We will share stories of how they are thriving using lessons learned from nature. And good news, it is working. Learn more by listening to Nature Answers wherever you get your podcasts. This is the BBC. Hello, I'm Robin Ince. And I'm Brian Cox. And today's show is about making the invisible visible. So basically, it's kind of about how physics has reached the point of being a made-up

science, where it just comes up with ideas about the universe, which we can't see and we can't detect, and then they say that just because they've made an equation about it, it means that the whole universe is made of vibrating strings or there's dark energy. It's not right. Well, that is, though. It is predominantly... Modern physics is basically... It's just made up, isn't it? Because that's what... I have to admit, when I watch your shows,

I don't believe them. It's not right. Anyway isn't it? Because that's what... I have to admit, when I watch your shows, I don't believe them. It's not right. Anyway, what is today's show about if it's not about just making up stuff because we can't see it and you physicists have, frankly... You are a branch of philosophy, I think, now, aren't you? Today's show is about how we can deepen our understanding of the natural world without using visible light. How can we speak with any authority about things we can't see?

How do we know there was a Big Bang? How do we know about life on Earth many billions of years ago? How can we say with certainty that maggots can smell? Today, coincidentally, we are joined by one of the world's leading experts on the origin of the universe and the world's leading expert on the olfactory sense of maggots. And they are... My name's Matthew Cobb.

I'm Professor of Zoology and Maggots at the University of Manchester. And I think the most wonderful things that science has ever enabled us to see are firstly when Anthony van Leeuwenhoek looked at his semen down a single-lens microscope, and then in the 20th century when Watson and Crick were able to realise the double-helix structure of DNA following the work of Rosalind Franklin and Maurice Wilkins. Carry on.

OK, Robin, yes, I know who I am. I'm Carlos Crenn. LAUGHTER Carry on okay, yes, I know who I am. I'm We have never had a physicist who has been that confident about anything in the universe And I know who I am. Well, I've made some equations suggested to 90% chance. It's a start We don't believe we know which is different from belief. Science is about evidence, not about belief. But let me tell you who I am.

I'm Carlos Frank. I'm the Ogden Professor of Fundamental Physics, whether Robin likes it or not, at the University of Durham. And I think the most wonderful thing that science has made visible is the beginning of the universe, no less. I'm Katie Brand. The closest I will get to becoming a professor of anything is one of those ones, those honorary ones

like they give out to people like Jerry Halliwell. So fingers crossed for that. I am a writer and an actor and a comedian. That's what it says on my intro. That the most wonderful thing that science has made visible that was invisible, I think, is an unborn baby uh because it gives any prospective parent another nine months of obsessing and worrying and staring at pictures and my least favorite thing that science has made visible that was invisible was is calories the number of calories in everything i don't need

to know the number of calories in everything even as you said they can even tell you the number of calories in everything. I don't need to know the number of calories in everything. Even, as you said, they can even tell you the number of calories in sperm now. Are they working out? Sorry, I don't know why I brought that up. Now, we are doing a Freudian special next week, so we'll deal with that then. And this is our panel! Carlos, we'll start off with you, because you had such confidence in knowing who you were.

And one of the things, we've talked about this before on the show, but the fact of what is invisible, 95% of the universe, approximately between 95% and 96% of the universe is invisible to us. What is it and how do we know it is there? Good question. First of all, let me first tell you what it is and then I'll tell and how do we know it is there good question the uh first of all let me first tell you what it is and then i'll tell you how we know about it one of the invisible parts of the universe is something we call dark energy and that's easy peasy because what the dark energy is doing is making the universe expand faster and faster and faster and that's something astronomers

can measure for breakfast because we can see how far away galaxies move and you can just see that the universe is expanding faster. So that's no big deal. The other more interesting part is what we call dark matter. And that is matter that keeps the galaxies together. So we know it's there because we see the galaxies. And what glues them together is this stuff that we cannot see, and it is known as dark matter.

And one last thing I would say about dark matter is you should be thankful for dark matter because if you wasn't for it, you wouldn't be here. The BBC wouldn't be here. None of us would be here because it is the dark matter that's responsible for the universe being as it is, for the universe having stars, galaxies, planets, and eventually Brian Cox,

Robin Innes, and infinite monkeys. Is dark matter different to dark energy then? Oh, yeah, very different. So what is the main difference between... But dark matter, just to put it simply for somebody who's not a professor... I live in Fingers Crossed, honorary professor of media. Dark energy pushes. It pushes the whole universe.

It's making the universe expand faster and faster and faster. And dark matter, as the Americans would say, sucks. It makes things contract. It pulls as opposed to push. So the dark matter is what we see in the galaxies, and the dark energy is what we see in between the galaxies. We're closer to understanding what dark matter is. We don't know yet, but we have more of a set of plausible theories

about the nature of dark matter than dark energy. Absolutely. I don't think dark energy is something that I worry about because I'll be probably long dead before anybody knows what it is. Dark matter, on the other hand, is a quintessentially, ultimately invisible stuff today, which I hope science will make visible within the next few years. I've been saying that for the last 20 years. And would you say it's probably some form of particle? It's some form of elementary particle, almost certainly, created very soon after the universe began

in the Big Bang. So it's some form of particle, and it's just very elusive. So in fact, I don't want to alarm anybody in the audience, but there are billions of these particles here going through your bodies as we speak. You just don't feel anything because they just go through, and that's precisely the curse for physicists who are trying to find them, because if they go through everything, they go through your detector, you don't see them. But we know they're there because we see the galaxies. They have to be there. So what makes them invisible is that they don't interact with light. They don't interact with anything.

They don't interact with themselves, they don't interact with other matter, except very occasionally, and so that's why they're invisible. Katie, how do you feel? Because the first time that I heard about the idea of particles that don't interact, it seems very, you know, as with both the non-professors on the panel, it seems very counter-instinctual, the idea of something which will not interact

with the scale of matter as we see it. Funnily enough, we're non-professors, but we are stand-up comedians, and stand-up comedians don't tend to interact very well with other stand-up comedians. In a way, we represent dark matter in human form. But, yeah, I find the whole subject is incredibly fascinating and it's sort of that sense of, like, this sense of flow in the universe,

that things are connected via matter that we can't see. But I've always wondered... I don't want to reduce this to anything sort of, you know, hippy-dippy, but whether that sense of sense of instinct or hive minds or when you see birds flying in formation, are they somehow responding to that kind of... There's some sort of flow of energy in the universe that is connective, even though it's not interacting.

Definitely not. OK, fine. I'm glad we've cleared that up early, because usually it takes me most of the show to get that sort of rebuke from Brian. But, of course, dark matter does interact through gravity, which is the one force that it interacts through, and that's how we see it and measure it. Well, exactly.

Well, it produces the gravity, so it gravitates, and so that's why it is responsible for galaxies being born in the first place. So yes, we know it's there through its gravitational effect. We just can't see it. It really is the quintessential invisible component of our universe. Matthew, is biology in a sense the same? Because it feels more concrete in a way, I suppose. We're talking about living organisms that we can see. But when we talk about our description of organisms,

the way they work, their evolutionary history, for example, then there is a... Well, the question is, is there a component of not only seeing but theorising and piecing evidence together in order to understand how they work and why they are the way they are? Well, you have to both...

One of the simplest ways you can realise the links between all mammals is by looking at their skeletons. So simply with your eyes, you can work out they've got this structure and there's a very bizarre structure that you wouldn't design. It's clearly not been designed that way. It's adapted, evolved over millions and millions of years. So you can see the similarities between yourself and a cat or whatever. But on a deeper

level, then we have to use other techniques for looking back into the past. And the primary way we do that is by looking at DNA sequences. So we can see the relationships between different organisms by their DNA and then people then produce visualizations

of that. So they will visualize it in terms of a tree or a rather complicated loop seems to be where we're going to now when we understand the origin of organisms like us which have many cells. So you need both the basic grounding. What's interesting is that the morphological, the way we look and the way we interact, those descriptions about how organisms link up and how they evolve have basically been supported by the genetic data.

So we get now greater insight into the fine detail of those evolutionary relationships, but more or less the way our bones are and where our liver is and everything else, that pretty much set out the relationship between, certainly, animals. I suppose we could define what we mean in a scientific sense by seeing, because, of course, we can't see DNA with the unaided eye. It's exactly the same principle.

Part of making the invisible visible is you have to use an instrument. You have to bring something to enable you to detect the consequences of some process or something. So it may be that you can see that two bits of DNA are different by, well, in my day, we'd make bits of them radioactive. And then you allow them to migrate on a gel under an electric charge. And the different bits of DNA would go to different places. And then you could see these little radioactive bands. They don't do it that way anymore, I'm glad to say.

But they still are using similar techniques to visualise something that we can't see with the naked eye. What techniques have usurped that then? What's the system now? Nowadays they will attach to the DNA different molecules which will reflect light. So basically the computer can do it instantaneously, virtually. So when I was sequencing DNA in the 1990s, if I got 400 base pairs in a day, 400 radioactive base pairs, folks, I was very happy.

Nowadays, then, a DNA sequencer is the size of a mobile phone. The latest ones, the ones that were used during the Ebola outbreak, they were sequencing whole DNA, whole genomes.omes and probably do it in a few days now incredibly rapidly all done on a little machine which you connect your computer with a usb cable can i just ask just in terms of because i think the scale of for instance you know the the full sequence of virginia what are we talking about for because billion letters so you've got dna is basically composed of four bases, A, C, G and T, and you've got three billion places in your DNA and mine, and, yeah, you need to know all those three billion places.

Most of them don't do anything, we think, or maybe they do, maybe it's like dark energy, maybe they are doing something, but only a small proportion are actually producing proteins or controlling the way we grow and develop. And there's an awful lot of stuff that's just left over from viral infections and stuff like that from the past. And what sort of distance scales are we talking about? How big physically is a piece of DNA with three million...

Three billion. You think you get it right. Billion, not million. It's astronomy. You get a patch of 1,000 between friends. Well, incredibly small. I mean, it's just a molecule. So, yeah, I mean, they're incredibly tiny. So that's how all those TV programmes

where they will get, in court cases, where they'll get a tiny amount of DNA, you can then amplify it. So you can use very simple techniques for making that even one or two molecules which are really really teeny let's just say say that teeny weeny weeny weeny so they'll fit there are loads and loads of copies of them in a cell and the cell is really really small this is i because i really like archaeology programs and it always amazes me about how much information they could get from someone who lived 4,000 years ago from, like, a piece of bean that might have been in their stomach

or something like that. It's incredible. Or they'll pick up a sort of tiny bit of bone and have a look at it and go, well, this person's main diet was probably rice and some wild boar. And you just say, how on earth are they... That's astonishing, the way you can get that amount... We seem to be... We know so much as humans about our own ancestry now but through being able to see the tiniest things you can create whole worlds out of something the size of your fingernail

i mean that's amazing it's getting even more amazing so you probably know that the human human cells are just falling off us and an awful lot of the dust you find at home is in fact dead skin cells. So the people who work in Denisova Cave, and Denisova Cave is out in Siberia, and it's a place that was occupied by three kinds of human ourselves, the Neanderthals and the mysterious Denisovans, about whom we know nothing except for one tooth and one finger bone. But these people have said, well, the researchers have said, well, why don't we just try looking at the dust? There's all this crap in the bottom of the cave.

Let's just try getting that dust and seeing what we can find, see who was there. So we may only have a tooth and a finger bone from the Denisovans, but perhaps there's Denisovan dust, and the sequencing of that DNA may be able to help us to get more insight into what they were like, how different they were from us and so on. Because I think looking at your jumper, there's a kind of problem.

Typically, of course, it's a jumper covered in dinosaurs, but I'm thinking now that the dinosaurs, of course, were having constant changes in what they actually were, and so you're taking a risk that your jumper may well be out of date just during the next paleontology discovery, surely. Well, the big problem with these is that none of them have got feathers on. So I'm kind of Spielberg-esque. Steven Spielberg said that he didn't want feathers on his dinosaurs

in the last Jurassic Park film because animals with feathers weren't scary. So he's obviously never seen an ostrich or been attacked by a cassowary or really looked at an eagle or, to be honest, any bird. I have some very aggressive robins in my garden. Well, they are. Robins are... Genuinely terrifying. Absolutely. Robins are horrible. So sorry. I don't know why I go there.

It's just, I don't know what you put in that upturned coconut, but it is delicious! Carlos, what's the... What's it... To a physicist, I mean, if you add to... The term see, we can see something, I can see it, therefore I believe it, is a colloquial use of the word. But in science, in physics, astronomy,

what do we mean by when we say we can see? Well, there are many ways of seeing. It depends what instrument you're using to see. So in reality, what we mean is not just seeing. I mean, we use the word because we see optical light. That's just one limited use of the word see. In science, what we mean by see is really to detect. So if you detect something, whether it is through light or through gravity

or through any other force, then we say we've seen it so that's why i often say we've seen the dark matter but let me explain what it is we haven't seen it with our eyes it doesn't produce light but we've seen it through its gravitational effect on bodies like galaxies so that's what we mean by seeing we mean detect because is it right because i've always had this uh sense from programs that i've watched and things not a professor obviously but um humans very much rely on light because one of our strongest senses is eyesight so people say like oh dogs don't have a sense of self because they don't recognize themselves in the mirror but then you think well a dog can recognize its own

smell so it must have its sense of self through the smell. This is a bit of a tangent. But what I mean is, is it possible that there are other animals on Earth that do understand and can detect dark matter because their different senses are more powerful and they don't rely on light and their eyesight to be able to see things? Well, two things. The only reason that our eyes can see visible light is actually physics. It's because the sun, which

shines, which I think is much more amazing than being dark, but in any case, the sun shines because it has a thermonuclear reactor in the center that just happens to produce radiation in the visible range, and that's why our eyes have evolved to be able to see visible. But whether there are animals

who can see, detect dark matter, well, apart from vampires, I'm not quite sure. No, I don't mean with their eyes. I mean animals that use other senses, or animals that aren't reliant on light, that are able to detect dark matter because they don't need their eyes to sense

things, to detect things. No, not really. She's got a couple of sniffer dogs she's trying to sell. Perhaps sniffer dogs could sense dark matter. But the animals that live deep under the sea or something like that.

Would you prove them that dark matter is so big? Yes, it's a good question, though, in the sense that there are animals, I think the catfish, but there are others, that build their picture of the world using measurements other than light. Yeah, you know, catfish will use electric... They can detect small electric signals from their prey and they live in very murky water,

so basically they're covered in taste cells as well. But I think the answer to your question, Katie, is no, there can't be such organisms, or if there are, they're not made a lot of anything any matter that exists on earth because what's happening when we're sensing something is that some of our stuff which is basically carbon and hydrogen and other stuff is reacting in some way to some stimulus another a chemical or a photon or whatever so we'd have to have there'd have to be organisms that were made of unearthly material that we've no idea what it is,

and then they could detect perhaps dark energy or dark matter. That's a shame, because what I was hoping was that catfish understood everything about dark matter and they're desperately trying to tell us, and we just keep catching them and eating them. Which would be a shame, wouldn't it? It's much better than catching and eating a physicist, but... Oh, Trump's America, you never know.

I wondered, in fact, just a little bit of history in terms of the different levels of us being able to observe the universe, then we'll come also to living creatures as well. So up to the point before the lens, what limitations then did we have of being able to piece together our image of the universe then we get the lens and and if you could then take us to where we are now in what instruments we're able to kind of interrogate the universe with well the lens you mean the first telescope

that galileo uh discovered well that suddenly opened the universe to scientific inquiry because we could now see beyond our own planet for the first time but that was only like we were just saying in the visible part so light what we call light in reality physics we call it radiation light this is one part of a spectrum of radiation which has many different types for example there's x-rays there's radio waves there's gamma rays there's all sorts of different types of radiation they're all's X-rays, there's radio waves, there's gamma rays, there's all sorts of different types of radiation. They're all the same thing. They use a wavelength, which is the way in which light oscillates is different. So the first window into the universe was the first telescope, which not surprisingly was optical. Then came radio telescopes,

which not surprisingly, you won't be surprised, Robin, detected radio waves. And they opened a new window into the universe, which led to the discovery of the Big Bang, to the discovery of big black holes, which can be seen, actually, in certain ways that we can discuss. Then came X-ray astronomy that revealed also the presence of black holes and the presence of hot gas in the universe. And then now we have gamma rays. And now, and just last year, a new window was opened into the universe

which made something previously invisible finally visible. And that was the discovery that many of you will have heard of, of gravitational waves, which is absolutely sensational, spectacular. And that is the newest window we have into the universe. Gravitational waves are produced by very big black holes colliding and fusing together and causing no less than the whole of space to vibrate. And these vibrations were detected last year. The Nobel Prize in Physics, no doubt, will be given to the discoverers of gravitational

waves. And now we have the last given to the discoverers of gravitational waves. And now we have the last open window into the mysteries of the universe. In biology, is there a frontier you can see? I mean, it's an interesting story, the gravitational wave story, because we knew they were there, but there was a very strong sense in which if Einstein's theory of general relativity is correct, then these things exist, we go look for them,

and it then opens a new window on the universe. Is there such a frontier in the life sciences? Well, obviously life sciences are messy and horrible and aren't really science, kind of an art form, in that we don't have the same kind of laws that physics has. We're subject to the laws of physics, unfortunately, but within that, life just gets on and does its own thing. So we haven't got exactly the same kind of predictions that you'd want to make and then go and build a massive device to go and test them. So it's much

more that people come up with new techniques which they can then apply to problems that they might not even have realised existed. So increasingly we are looking to use new techniques for identifying cells in particular, for being able to label cells, for being able then to reconstruct cells. So there are colleagues in America who are at a place called Janelia Farm who are working out the wiring diagram of a maggot, just one. They got one maggot, they sliced it up, and now they are working out how all those cells interconnect. And there are probably about 300,000 cells, something like that, in a maggot.

And how the neurons in particular, how they speak to each other and how they relate to each other. So the idea being that in the end, you'd be able to build a robot maggot, you'd be able to model that maggot, and then you would be able to test your theories. Is it like magicians when they say to the lady, don't worry, we'll put you back together at the end? They said to the maggot and then you will be able to test your theories is it like magicians when they say to the lady don't worry we'll put you back together at the end they said to the maggot honestly this will take 20 minutes and we'll put you back together just trust us and you'll be fine you won't even know it's happened i think that's probably true i don't think she knew what was

happening the complexity of biological systems as you say is is quite remarkable in that sense that that it's cutting edge 21st century technology now to work out the wiring diagram of a maggot. And even then, the individual cells out of which the maggot's made are not fully understood, it's fair to say. No. So, as Sir Martin Rees said, an insect is more

complex than a star. We know roughly when the sun is going to go out, but you don't know which way a maggot's going to turn. There's an inherent stochasticity in behaviour that means you can't always predict what it's going to do. A maggot is much more complex than the whole universe. So people often think that we do the fancy stuff

just because the universe is big. But actually, you are the ones who do all the fancy stuff because it's not size but complexity that makes things difficult to understand. So I have all the time in the world for biologists who study really, really hard things. We do the easy part. I'm just excited about the fact

there's going to be a Haynes manual of the maggot. I've been waiting for that for a long time. Carlos, you mentioned the radio astronomy and the advent of radio astronomy allowed us to prove that there was an origin to the universe, the Big Bang. Could you talk about that a little bit? How those telescopes allowed us to prove it? Yeah, that was, again, one of these...

Many of the great scientific discoveries have been made by chance. And in this case, two people who became very famous stumbled upon the Big Bang. And what they were doing was they were building a radio telescope somewhere near Princeton in the U.S. and they had very modest aims they were hoping to be able to detect radio waves from the sun that's what they set out to do so they build this this radio telescope. They turned it on, and they could see radiation. They could hear, actually, because this radiation is in the form of radio waves. You hear them. You don't see them.

These were actually radio waves that we call microwaves, which are radio waves. And they could hear this hum coming from everywhere. Now, they had actually discovered the Big Bang without realizing. So what happened was that they would point the telescope in different directions. No matter where they pointed it, they would always hear this hum, this radiation that seemed to be coming from everywhere. At one point, they actually thought they nailed it. They climbed inside the telescope, and they found the bird's nest.

And they thought, oh, these must be bird droppings. So they cleaned the telescope and they said, now we can see the sun. They still had this radiation because without realizing, they had discovered nothing less than the heat left over from the Big Bang. Big Bang, when the universe began, was very hot and very dense. But because the universe has been around for a rather long time, it has cooled down. So this heat has now cooled to very low temperatures, up 2.7 degrees above absolute zero. And at that temperature, the heat becomes microwaves. So what they had detected accidentally was the heat left over from the

Big Bang, the radiation that was reaching their telescope, having travelled throughout 13.7 billion years since the Big Bang, cooling and then turning into microwaves and producing this hum, which they erroneously ascribed to bird droppings. How's that for one of the most important discoveries ever in science? I love all those discoveries, because all the ones in the past few hundred years, it always seems to be an accident, doesn't it? It's always sort of like, I was trying to make the perfect pint of beer and somehow I discovered oxygen.

But now it seems much more efficient and targeted that scientists know what... They can predict what they want to look for and then how to make the instrument to look for it. Yeah, and I was talking about that before. So it works both ways. Sometimes you have a theory and then you test it. In this case, it was just an accident.

It turned out that there was a theory that had predicted that radiation should be there because some clever people had already figured out that the universe should have started with a Big Bang. And just in fact, this is one of these great coincidences in science. These people, Penzias and Wilson, the ones with the bird droppings, they were working at Del Laf. I'm sure they'd be delighted to be described.

20 miles away in Princeton, three of the greatest scientists of the 20th century had figured out there had been a Big Bang, had figured out there had to be radiation. They were building a radiometer, and they got scooped by a few months by these two people who just accidentally stumbled upon it. So occasionally, science does work by accident.

But usually it works by design. We're talking about origins here, in this case the origin of the universe. So we're talking about inferring a point in time, an origin, the Big Bang. I suppose in biology, the parallel would be the origin of life, something that we will never see. It's in the past, a long time ago well somebody might make

it in a laboratory they might remake it so we might get some idea of the processes but no we're not going to see that event well this was my question how we can begin in a similar way i suppose to it to approach the the big bang of biology the origin of life on earth well the way that people are doing it is trying to see, well, what's common to all organisms? What's the minimum number of genes you need to survive, and which are the genes that seem to be probably those associated

with survival in what were probably the rather difficult conditions when life first appeared? So they are then trying to recreate cells with a minimum necessary genome, and then trying to see cells with a minimum necessary genome and then trying to see whether they can survive. And then there are other people like our friend Nick Lane at UCL

who's actually trying to look at the processes involved and he's not trying to create life in his test tubes, but that is ultimately what would be the aim of all that. It's a difficult question. I mean, it's obviously a difficult idea that one day there was no life and the next day there was life. But I could ask you the same question about the universe.

There's this wonderful idea, a day without a yesterday, that wonderful quote from Georges de Maitre. So what do we know about that? It's impossible to visualise, isn't it? Do we know anything about the day without a yesterday and what happened before that? No.

I think we scientists have to be honest. We know lots of things, but there are many more that we just don't know, and this is one of those. So we don't know what went bang. We know there was a big bang, but what went bang and why it went bang, we have no idea.

And I think some people would try to hoodwink you into saying, oh, yes, the universe is started by some quantum fluctuation. I think that's all bullshit. We just simply do not know. But the interesting thing is, well, here's the interesting thing, Robin, is not only we do not know, we know why we do not know. And the reason we do not know is because we have these laws of physics which work very well they allow us to send rockets to the moon and do all sorts of detect gravitational waves but these laws of physics themselves tells us that they break down as we try to answer these questions that brian is asking so the laws of

general relativity and quantum physics break down when we ask questions like what was there before the big bang and you didn't even need to go that far even when we ask questions like what was there before the Big Bang. You didn't even need to go that far. Even when we ask what was the Big Bang like, the equations just don't work. They blow up, as we say. They show infinities, things that mathematicians don't know how to deal with. So what happens is our theoretical understanding is limited. We have this beautiful theory of general relativity

that predicted gravitational waves. We have quantum physics that predicts phenomena that physicists measure every day. But we do not have a theory that merges the two together, which is what we would need to answer these questions. So I confess, I put my hand up. I don't know what was there before the Big Bang. I wish I did, but I don't. And I won't with the current tools of physics. Is it the case that then, if the day would know yesterday, that this concept of time began with life, with the origin of life, that without life, there is no sense of tomorrow or yesterday? There isn't a linear progression. Would that be the case? Feel free to clap, but I'll take...

I'll take anything I can get at this point. I hope we'll still be friends later. Oh, God, I can't wait. The answer is no. Right. Absolutely not. I don't think... I mean, time has nothing to do with us being here, so we can observe the universe when it was a lot younger than it is today, where there was no way life could have evolved

because there were no stars or planets. So we observe this radiation that I was talking about before. Surely there was time then and there was no life. Although, you know, some quantum physicists might side with you and tell you that reality doesn't exist until you measure it, but I think we shouldn't go there tonight. You're quite a punchy physicist, don't you?

You're going to come out fighting. Katie did hit on a great question earlier, though. That's a question about how uniform that glow is from the Big Bang, the cosmic microwave background. And that is a window onto very early times, isn't it? Because it isn't quite uniform.

Right. OK, Katie, you win here. So the... APPLAUSE Wait till I tell you what's coming. That professorship is within my grasp. Wait till I tell you what's coming. So what I'm about to describe is something that,

even though I'm a grown-up man, born in a Latin country, brings tears to my eyes every time I see a particular graph. And that has to do with this question. So what happens is this radiation is not completely uniform. You're right, it's not completely uniform. It has tiny little irregularities, but really, really tiny. One part in 100,000. Irregularities in the temperature.

So one point is hot, the other one is slightly less hot by one part in 100,000. Now, the thing is, in 1980, physicists predicted that the pattern of temperature of these radiations should exhibit these hot and cold spots. That was predicted in the 1980s. In 1992, that pattern was discovered by a satellite that the Americans launched, NASA launched, called the COBE satellite. It discovered, many of you might remember, this glorious front page in the independent newspaper

that said how the universe began. So this pattern of hot and cold spot was discovered. And verifying everything we think we know about the Big Bang. But the most incredible thing is that these small irregularities is what later grew under the action of dark matter to produce the galaxies like the Milky Way in which we live. So this is the blueprint of today's beautiful universe of galaxies is there in the radiation from the Big Bang,

and it is known, it is detected, and it is now measured with an accuracy of a few percent. It's just sensational. Matthew, when we talk about this sort of fundamental physics, people often talk about a theory of everything, by which some people mean the quantum theory of gravity that Carlos described we need to describe the Big Bang even possibly. Does that make sense?

It's a very physicist way of thinking, a theory of everything, which implies that we have a theory that can ultimately describe living systems as well as stars and planets and galaxies. Do you think such knowledge will be available to us? Well, in principle, because everything's knowable, although maybe not the beginning of the Big Bang, but virtually everything is knowable, although maybe not the beginning of the Big Bang, but virtually everything is knowable.

So in principle, yes, it should all be able to be integrated, but you would have to... I think it's way beyond our comprehension as to what that would involve. So if you think about the theories or the fundamental bases of ideas about life at the moment, then they are things like, well, all life is made of cells. That's what's called the cell theory, which came about in the 1830s. And so you'd have to fit that

into your idea. It's a different kind of theory. It's a different kind of lawfulness from what you talk about in physics. Or the evolution by natural selection, which again is a fundamental aspect of biology. It's present in all life. It's essential. If life exists, then it will show those kind of processes. So, again, any theory of everything would have to not only involve quantum fluctuations, but also giraffes and hippopotamuses and ants and things like that. Do you think it's a prejudice? It's a very, obviously, reductionist way of looking at the world,

to say, well, there's fundamental science, which is the are quarks and electrons and quantum fields, and from that we could build a picture of complexity in the universe. Is that appropriate? It's something I remember arguing about when I was an undergraduate, and I don't think

we've really got much further, so the question is, are all phenomena reducible to those basic physical laws, or are there emergent properties that come by some higher-level interaction? I'm very much on that second view and haven't changed much in the last 40 years, but then, you know, who knows what the future may bring about.

So ultimately, for example, something like consciousness would be the ultimate emergent property in that picture. That's what I assume it is, but on the other hand, it's a physical thing. So there's nothing spooky about it. It's the activity of neurons in our brains, so ultimately it's electrochemical activity, and in some weird, magical way,

then it has me sitting in my head, looking out of my eyes, looking at you. So can you see it in that sense, then? Going back to the subject of this programme, remember, ages ago ago now we had a subject. It's interesting though, can you see consciousness? Would that mean we understood it fully? Brian, it's a pretty brave decision right

at the end of a show to suddenly bring up consciousness. Undoubtedly one of the... I imagine this will just wrap up pretty quickly and Matthew will say yes, it's probably, I think just at the corner of the front row, possibly the hypothalamus. I was bringing to a close that wider question of what we mean by see.

Do we mean understand? Do we mean detect, as Carlos said? Well, I think first we've got to detect it. So before you've got to be able to detect and measure it. Difficult in 2016. Measuring consciousness, I think, is very difficult. Consciousness is spooky, I think. Define spooky.

Without using Einstein as well. It's no more spooky than quantum entanglement. Or measure, or examine in the laboratory. That's what I mean by spooky. So spooky action from distance, then. This is brilliant. It's come full circle, because now the physicist is accusing the biologist of dealing with things that you can't see.

You're measuring up. LAUGHTER See what you did? You started off, Katie, as our chair of theology, and already now, just half an hour in the company of you, and we've got a physicist going, Hmm, spooky spooky it's this kind of dark energy that i emit i'm pushing through your physical beings and bringing you over to my side carlos do you think is it just because i mean matthew you were saying that nearly everything could be could be knowable with enough time

and with a continual move in terms of improvements in technology, etc., would you believe that everything could be made visible if we consider the visible to be the comprehension of its existence? I don't think so. I think nature is unlimited and I think there won't be

enough time because as we know, the sun will eventually die out and so we will. But even if there wasn't, even if we because, as we know, the sun will eventually die out, and so we will. But even if there wasn't, even if we could go to some other planet, I think the mysteries of the universe are unlimited. I don't think there is a limit to knowledge or a limit to what we can learn.

That was spooky as well. I think that's part of the beauty, isn't it? If you have entered into a world right from the start knowing that you're not going to go, and now I've come to the end of it, there's no conclusion, there's grand moments on the journey, but you go, oh, and that grand moment's now led to all these permutations as well. I think it's a wonderful thing.

The mysticism of science, sorry, I know this is a bit heretical, but it's part of what I find attractive about it, even though I'm not very good at it, because I went to a convent school and wasn't taught any maths until I was nine. We just did art and Jesus. Which sort of explains my whole career.

But the mystery of science I find very attractive, and I sometimes look at religion and the early religious figures going way back into the bible and even the kind of the three wise men in inverted commas who were astronomers you know these these were people who were trying to figure out the universe they didn't have the tools or the instruments they were trying to make theories about the universe even the genesis story of you know in the beginning there was light and in the

beginning you know these these are not wildly inaccurate if all you've got is your eyes to look up into the sky. And I think the sort of continuation of religion into science... At some point, science will make all of religion obsolete. I think that's probably the case. But it's just this sort of false divide, isn't it? Because what

early religious figures were were scientists trying to figure out the universe. So there is that sort of mystery to it. What is wrong with Brian and you? We're trying to figure out the universe. So there is that sort of mystery to it. What is wrong with Brian and you? We're trying to wrap up the show. He goes into consciousness and you think we'll probably wrap it up by religion versus science. No, no. No, I...

APPLAUSE Can I say... Can I say that I agree with Katie? I think... LAUGHTER I just want to... I'd like Katie. I think... And I just want to. I'd like to get Matthew's opinion. Because I think that the motivation

for religion and for science and for exploring the universe, they have the same motivation, which is to notice there's something worth explaining, notice that the world is beautiful, and then you proceed from there. So I think the inspiration for these many different ways, art, science, literature, religion, the motivation is the same, I would argue.

Well, the good thing is... I don't think so. You don't think so? See, this is what I knew! Because the essence of religion is that it's a solace. So it's the heart in a heartless world, as Marx put it. It's a way of actually trying to make yourself feel better about the awfulness of existence. Science may have that motivation,

but ultimately it's simply about finding things out. And you have different tools, of course, to find them out. So we have experimentation, we have theory, and most religions are impervious to that because it's based on faith. But surely all of it is exploring the human condition and trying to figure out our place in the universe, our experience of the universe, what it means, why we feel it, why we see it.

I know that religion lays morality on top of that, which science doesn't, but really it's trying to get to grips with human consciousness, which is very complicated. Now we're back with consciousness again. Round and round and round and round. I will put it frankly, these are two great shows,

but neither of them are the show we were doing. I mean, what time actually is it? It's only about Stockholm Syndrome. It really is kicking in with some of them. One of them is dressed as Patty Hearst at the back. It's only 25 to 9. I think

the point, Casey, which I agree with is that I think all you said was that initially you have creation stories, for example. So there are questions about origins, about the way the world works. They're addressed in a particular way. And now, as you said, there is

a better way of doing that if you're talking about how did that happen? How did we go from a hot, dense Big Bang through to the formation of galaxies? You're not going to find it. And it's connected to when humans began to be able to grow food and agriculture and in the more fertile parts of the world

that once they'd taken care of their basic needs, they had time to look up and think, what's that? And that is the origin of science as well as the origin of religion, isn't it? Well, we asked the audience a question, and the only way to pretend none of that happened...

No, it's a good, it's a very good discussion. What's that? That is a good... That is the origin of science, isn't it? What's that? I'll tell you what that was half an hour ago, our producer giving the ten-minute signal. I'll put a fresh coconut in the garden. We're going to come back. Oh, yeah, no, no, don't worry.

We're going to come back to this. We have the same panel. This is basically the perfect end of the series. What a cliffhanger. Consciousness, religion, how's it going to end? It's not going to end. I know that, Carlos. Robin, I've just got one last question. What about free will? Uh-oh.

It's an illusion. It's an illusion, but it's an illusion that we have to go with for the time being. So we asked the audience, if you could make something invisible, what would it be? The very tall person sitting in front of me. This is a good one. The signs to homeopathy clinics. The Donald Trump's hair. I've already had some success. I would like to finalise

the process. Wavelengths of light around 400-500 nanometres. I've had enough of blue. My husband's rocket mass heater project. And preferably him too. Brian's trousers. Donald Trump's trousers. The Tower of London, because I enjoy confusing ravens.

So, do you have any others? Some of the more avant-garde answers as well there, so thank you very much. Thanks to our panel, Katie Brand, Carlos Frank and Matthew Cobb. Now, this is the last episode of this series of

Monkey Cage, and this also was the last episode that was commissioned before the world went post-factual. So Series 16 will reflect the new world order. So the first in our post-factual series will be the excellent subject of a cutting-edge examination of the ability of telepathic dogs to communicate with ghosts. And that panel includes Barbara Woodhouse, Houdini, who's not happy about that,

and Rin Tin Tin, the dog that saved Hollywood. And then we're going to do Global War Minutes Freezing in here. How aliens built not only Stonehenge, but also the Blue Water Shopping Centre. And we're going to do a panel on why opinions are better than evidence-based medicine. And we're having trouble do a panel on why opinions are better than evidence-based medicine. And we are having trouble getting a panel for that, actually, because at the moment, a lot of them

are very poorly. So, we will see you for Series 16. Thank you very much for listening to this series and we'll see you back in the summer. Bye-bye. APPLAUSE In the infinite monkey cage. Till now, nice again. This is the BBC. the first radio ad you can smell. The new Cinnabon Pull Apart, only at Wendy's. It's ooey, gooey, and just five bucks for the small coffee all day long.

Taxes extra at participating Wendy's until May 5th. Terms and conditions apply. In our new podcast, Nature Answers, rural stories from a changing planet, we are traveling with you to Uganda and Ghana to meet the people on the front lines of climate change. We will share stories of how they are thriving using lessons learned from nature. And good news, it is working.

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