The Infinite Monkey Cage - Magic Materials

Episode Date: March 25, 2023

You might think materials are a bit boring and inconsequential but without them we would still be living in the stone age. Brian Cox and Robin Ince are joined on stage by material scientists Mark Miodownik and Anna Ploszajski and comedian Ed Byrne to discover the life changing materials that are hidden in plain sight. Which materials have made us human? Which materials do we completely depend on? And how will materials shape our future?Producer: Caroline Steel Executive 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 first radio ad you can smell. The new Cinnabon pull apart only at Wendy's. It's ooey gooey and just five bucks with a small coffee all day long. Taxes extra at participating Wendy's until May 5th. Terms and conditions apply. BBC Sounds. Music, radio, podcasts.

Hello, I'm Brian Cox. I'm Robin Ince. This is the Infinite Monkey Cage. Now, why are there no space elevators? Why has nobody built a Starship Enterprise? Why are there no hoverboards? Why are there no cardigans that don't shrink after a hot wash? There's no give. There's no give in the cardigans. These are all questions for material science. Which materials have changed the direction of civilisation? What materials couldn't we live without?

And how will materials determine our future? Today, we are joined by a material scientist, a comic who was duped by Zaphod Beeblebrox, and a professor that I once made oobleck with. That's the weirdest intro, isn't it? Does anyone understand that? Yeah, right. This is a thing. That is a very evidence-based intro,

because everything that I have said there is true. I'm going to admit this, right? Our producer said, I've never heard of Zaphod Beeblebrox. Who's that? Yes, and that is exactly the reaction I said. Can I just find out from this audience who here's heard of Zaphod Beeblebrox? Yes, there that is exactly the reaction I said. Can I just find out from this audience who here has heard of Zaphod Beeblebrox? Yes, there we go.

Who here knows what oobleck is, right? That's still enough people, aren't they? And they are. Mark Miodovnik. I am Professor of Materials and Society at UCL. And my favourite material is silica aerogel. I brought some with me. And it's my favourite because it's absolutely extraordinary. It's 99.8% air. It's this incredible colour blue. And it's blue for the same reason the sky is blue. NASA fly around the solar system to collect

space dust. And it's the only material i know that if you put some of it in someone's hand and say this is from a space crash they will actually believe you it's that extraordinary so i'm just oh i've just broken it it's that bad it breaks very easily it is brittle i forgot to mention that that's one of its downsides if it wasn't brittle i think you'd be wearing clothes made of aerogel filling especially in the cold because it's one of the best insulators on the planet. I'm Anna Podjaisky. I'm a material scientist and science communicator.

And my favourite material is a little bit more down to earth. My favourite material is actually wool. And this is because, as material scientists, we're in the business of designing new materials that have never been made before. And when we try and design textiles, we try and design them so that they are strong, they will last a long time, they will be insulating but breathable, they'll be biodegradable preferably so that they don't end up in landfill forever. Wool got there

many, many, many centuries before us. We are still trying as material scientists to design materials that are as good as the ones that nature has been making for many, many years. So my favourite material as well. My name's Ed Byrne. I dropped out of a BSc in horticulture and my favourite material would have to be George Carlin's routine about the words you can't see on TV. Quality bit. But no, as an outdoorsman and a hill walker, my favourite material is Gore-Tex, invented in the 60s. They were stretching Teflon just to make it go further and then realised it created air holes,

air holes that were big enough to let water vapour out but keep water droplets from getting in. And that revolutionised the outdoor clothing market and I wear nothing else. And this is our panel. Mark, you're a professor of material. We should start with the definition. So what is a material? Well, that is a really difficult question to answer, which is a weird thing to say as someone who's a professor of it. But it's actually very hard to define what material is because obviously

materials are made of stuff. So that's atoms. But to define what material is because obviously materials are made of stuff so that's atoms but then okay well other things are made of atoms too so is everything a material is a house a material and that i'm afraid to say we find very difficult to say because as things get smaller and smaller smaller i'll give an example your smartphone has a layer of indium tin oxide onto it. Now, that's a material, but your smartphone is made of many, many different materials, but you don't call it an incredible smart material. You call it a phone.

So at some point, the materials become so complex, so part of your everyday life, that you forget to call them materials. If you were to just ask your average punter, do they know what the word material means? They'll say, yes, obviously. But you ask an expert on materials and he won't be able to

answer the question what material is. So that's what academic study is, isn't it? Academic study is refining the question until there is no answer. Then it's marvelling over 30 years. But it will have been someone who is a material scientist who invented Gore-Tex, not someone who went,

I know what material is. You'd have worn their anorak and gone, oh, I'm warm and wet. It was the son of the owner of a Teflon factory who was just trying to be mean and stretching Teflon who accidentally discovered it. So, again, not really an expert material scientist. Yeah, there is science that's been moved on either by experts or frugality.

It is, yeah. It's just dumb luck. You said, by the way, there's a layer of indium tin oxide on your phone. Yeah. What is that doing? So how does your phone know you've touched it? Well, it needs to know somehow the skin is on it.

And you'll notice, because if you try and touch it with other things, it can tell the difference. So it's actually measuring the conductance that your finger puts on it and that means it has to be a conductor but there aren't many conductors that are transparent because if it wasn't transparent your screen wouldn't work very well so it's got to be on the outside of the screen it's got to be transparent and it's got to be a conductor and there are very very few materials that do that and one of them that's economically affordable is indian tin oxide that's not naturally occurring. That was a constructed thing. Yeah, it's not naturally occurring. And so that's what material scientists do. We spend lots of time in the lab working out

what different properties materials have, making new ones, making predictions about which ones might happen, and then testing them. And that Indian tin oxide is one of the key materials to make smartphones possible. I mean, without it, the smartphone becomes, you know, dumb. Because that's how I would have defined it. That's how I would have defined material, which is that it's something that humans construct or invent that does not occur in nature. But, Anna, you then chose wool.

Yeah, well, I've got a bit of an easier way to work out what is a material, which is named after my friend Amanda Morgan, who told me about it. She's not a material scientist at all. The Amanda Morgan method is it's a material if you can make a jacket out of it. And I'm yet to find that that is not true. Does it have to be a wearable jacket?

Is it one that Ed would wear for yomping around? Or how broad is our definition of jacket here? So as long as you can make holes for a head and arm. Yeah. Or, like, connect little bits of it together enough. For example, aerogel, you could make a jacket out of that. It'd be quite brittle, you'd have to stay quite still. You could.

And that's why you left working for Topman, didn't you? So in terms of the history of material science, I suppose you start with technology. You might say, well, there's a flint and you can connect it to a piece of wood to make a spear. When do we start seeing the first human-made materials? For me, and this is probably debatable because of the whole jacket thing

but um for me the first human made material was bronze because that was something that doesn't exist in nature you can make a jacket out of it um and we purposefully engineered that as a material we took two constituent metals that we got out of rocks put them together and made a brand new material that didn't exist before, and that was bronze. What property does bronze have? It's made of what, tin? It's copper and tin. Copper and tin, yeah.

So what property does bronze have that neither copper nor tin have? I'm curious as to why it's so important to combine the two. So generally, when you have a pure metal like copper, it's generally quite soft. So if you were to make a jacket out of copper, for example, I'm sorry, I keep going on about this. What's good for you is you're not wearing a jacket. That's what quite soft. So if you were to make a jacket out of copper, for example, I'm sorry, I keep going on about this. What's good for you is you're not wearing a jacket. I'm wearing a jacket and I don't have the jacket obsession you do.

When metals are made out of just one element, like copper, for example, it's quite easy for those atoms to move past one another, in other words, to deform the material. So if you had a jacket made of copper, you could probably bend it with your bare hands. It'd be quite flimsy. When you add a different element into there, like tin, what's happening at the atomic scale is that atoms of copper are being replaced by atoms of tin. And when you do that inside the atomic structure, it means that those atoms can't move as easily

because these atoms have different sizes, right? So when you put the tin atom in place of a copper atom, it forms a bit of strain in the material. In other words, it makes it harder to deform. And so bronze was a material that was harder and stronger and stiffer than anything that had come before. So it made it much better for making weapons and you could make sharp knives with it that wouldn't blunt

because it was an alloy, not an element. I always wonder how people decided to do that. Because, of course, it's long before anybody knew about atoms, so nobody knew why. So why would people decide to take tin and take copper and melt them? It was the guy, wasn't it? There was an athlete who always came third and felt very unrewarded.

Is it maybe somebody didn't have quite enough tin to do the job they wanted, didn't have quite enough copper to do the job they wanted and just mixed the two together and went, oh, it's not. Because it's a remarkable thing, isn't it? And it transformed the history of acid. That is actually how brown paint was invented.

Brown didn't even exist as a color until somebody just got all the paint that was left over and mixed it together and discovered brown that was the brown age is there any children listening to this this is untrue i'm lying i'm lying for comedic effect and not even that comedic. Yeah, I had to say that because there was no laugh, so people took it seriously. Before the Bronze Age, which is the first man-made material, you might argue, and Anna does argue... Sounds like you don't agree. There's the Stone Age, right?

So the Stone Age is a million years and the rest. So for a million years, humans are content with these stone tools and knocking about the place, and things are fine. A million years! And then someone, someday, is having a fire, presumably, and puts a rock in there, which they happen to get from somewhere, or they like the look of it, a green rock, malachite, it turns out, is probably the one it was, a copper alloy rock. And the next day, in the fire, because they got the look of it a green rock malachite it turns out it's probably the one it was a copper alloy rock and the next day in the fire because they got the conditions just right

hot enough and reducing atmosphere it's a lump of copper that moment changes everything then we get the copper age the bronze age the iron age civilization cities us having a lovely time and the smartphone so there's that moment right where that is an accident maybe or a moment of genius but surely we should have a national day of celebration of that day but it right because we'd otherwise be living in the stone age presumably it didn't just happen in that one single moment though surely for something like that in those days to have caught on it must have happened a number of times in isolated incidents no no oh i don't know but it's debated sorry it's debated no but it does come from one region and so it's not like it happens everywhere

in the world i mean maybe you say the chance of it happening is so rare that all through that million years it could have happened it could have happened it could happen or it did happen and people didn't notice because they were too busy hitting each other with stones but there's a very smart person who did notice and then they shared the information too busy hitting each other with stones. But there's a very smart person who did notice and then they shared the information. Too busy hitting each other with stones to notice there was actually a far more efficient way of hitting each other.

But it's a great mixture of stupid and clever because someone's stupid enough to say, we've run out of logs, we'll just burn these rocks. And then someone else goes, hang on a minute, that was a stupid idea, but there's something in that rock. They were probably heating the rock. You'd put rocks on a wood fire to then move those rocks to somewhere where you want the heat to be.

Like if you're in a tent, for instance. Well, you have them put on your back, don't you, when you go to that special health clinic? That is actually true, isn't it? Cut that, he doesn't like that. You've described this, the chance discovery of materials perhaps bronze and so on but we've become right towards the present day now where we're actively looking for materials as you said the materials in a smartphone so could you run through a few

of the materials that people won't be aware of probably that they're used every day i guess the first material that is a miracle material which we take for granted is stainless steel so steel comes up the iron age we have steels then and they're the perfect tool material and they make a lot of technology much more possible and there's a massive increase in civilization as a lot of steel but all the way through steel's the rusty material so although it's strong and stiff it will rust and so it's not as good as silver or gold and then it's the 20th century before someone posits the idea that, hold on a minute, if you alloy steel with chromium and nickel, we can actually stop the rust forming.

But not just that, because it formed a transparent oxide layer on the surface and that just protects it from oxygen rusting it. But then if you scratch it or by having to hit it or in any way, that layer self-heals and continues to stop it that's stainless steel now that's the 20th century and you can go to any kitchen and you'll see loads of this amazing stainless steel you take that back in time and they would call you a you know a magician they would you know a witch they would they would just would not believe that steel could be stainless well surely just for going back in time, that would prove that you're right. That would be a red flag.

That's not the thing that surprises them. It's like, what's that knife made of? The man who stepped out of a portal from the future. What a shiny object he carries. Anna, in terms of materials that people may be familiar with, but are complex and wonderful things. Yeah, I mean, we've talked a lot about smartphones. I think if there was one material that suddenly disappeared from our world that we would really, really notice, speaking personally, it'd probably be silicon, right?

Which is kind of the beating heart of the smartphone. It's the beating heart of our digital age. And silicon is kind of a funny material. material it's a semiconductor which we're mostly familiar with conductors right metals that conduct electricity glass which is an insulator that doesn't but semiconductors are this kind of weird sort of halfway material that are only conductive under certain circumstances semiconductor physics is all about how you can sort of flavour silicon in different patterns in order to make a material compute and make it think, which is what we've built our digital age with. And it's only silicon that can do that? Silicon is the one that we tend to use, but there

are others. I'm just wondering if you're silicon and you can become part of a chip that powers a supercomputer or you could become part of a fake boob. Like, it's a real... That's the two lives of silicon right there. See, that's the difference. Your silicone is the boob. And not any more, even. So it's saline now. But... If we can invent a smart boob, though, that would be really good. We've jumped very quickly there from kind of bronze to stainless steel. And what I was wondering, Anna, is that process again, when I'm kind of mocking that idea of sometimes the stupid and the clever, but also ideas of alchemy as well.

You know, those ideas of the search of how we might be able to make gold. Did that play its part? You know, that part of something which we now almost see as wizardry. gold did that play its part you know that part of something which we now almost see as wizardry also within that journey would we have found new metals new materials etc yeah totally i mean the alchemists were kind of the precursors to today's chemists right they were the ones that were regularly experimenting with matter with the ultimate goal of trying to transmute materials into gold we know that they never actually were able to do it today we can do it in particle accelerators in a very tiny amount

but that took a lot longer to develop going back to the fact that it was actually done in a particle accelerator i think was in the 90s wasn't it when it was first done where somebody actually did manage to turn some lead into some gold could you imagine playing Dungeons and Dragons with that person who actually did it who actually I actually am an alchemist so what I say none of you play Dungeons and Dragons also to be honest I think the first thing they thought was could you imagine playing Dungeons and Dragons with someone who works at CERN yeah yeah I reckon there's a lot of games of that being played I mean what are now this idea of managing to manufacture elements using particle accelerators you know what are the current imaginable possibilities Mark well so we have the periodic

table so it's good to probably start with like what we know about the different types of atoms there are. So there's 100-odd types of atoms that naturally occur. I'm not going to sing the song. Sing the song. There's... It will cut to an AI version of me singing the song now. Cut back. And so as the elements get heavier and heavier and heavier,

they have different properties, and that was incredibly exciting and people like oh wow how many can there be and this is this business about like in the universe which elements are possible and could we go to another planet and find that there are elements that are got 150 protons in their nucleus would that be stable could we make one on earth what kind of properties would they have and these are really exciting ideas. Mostly, though, our experience of those heavy elements is that they immediately fall apart. But there are people who posit that there are some islands of stability in the periodic table that are further away that we've never ever experienced. And so there are people thinking about most of the heavy elements are unstable, radioactive, but could there be some that are not?

And can we find them in the future? And how close are we to a safe and sustainable way of synthesising unobtainium? I mean, I think one of the things that, I guess, material scientists really enjoy is that, you know, there may be the stable elements, 100 or so, but you can make an infinite number of materials out of it. And I think that's the difference between a material scientist and, let's say, a physicist who studies atoms,

which is that it's the combinations of the atom types. And there are an infinite number of combinations that mean that you can invent materials that we haven't even begun to scratch the surface of thinking about yet. Those properties probably exist. We just haven't worked out how to make them and how to make that future come into existence i'll give you an example superconductivity right everyone thought well

you can't have a conductor that doesn't have resistance and that means that's why we lose so much of our electricity to to the grid because you know we're pumping electricity through and most of it gets lost as resistance but if you had a superconductor that had no resistance then overnight we would like solve one of our big energy problems. So of course material scientists are after making this stuff. And it exists, but it only exists if you cool it down to very cold temperatures. But could you get a superconductor

that would be room temperature? Literally overnight, the world would be a different world. Almost everything to do with energy policy and our technology would change. But no one's found one yet. And that's the great thing about material science is because you're always waiting for someone to suddenly announce that they've been beavering away in their lab for 10 years and unobtainium has been created. Mark you mentioned stainless steel as a

self-repairing material perhaps the first example of such a thing but now that idea it's quite a remarkable idea that a material when damaged can itself. And that's getting much more advanced, isn't it, in terms of the development of new materials? Yes, there's a big effort, and we're doing it in our lab too, to try and create materials that heal themselves. So not just stainless steel, but a whole wide range of them. So, for instance, we make bridges, we make buildings out of concrete and steel. And when they get damaged, we have to kind of, first of all, notice their damage, and then we have to go in and repair them and that costs a lot of money.

Wouldn't it be great, we think, that if the materials we made bridges out of and tunnels and buildings healed themselves? And we know it's possible because we are examples of that. So we are self-healing beings. Most of the reason why we live at all is because our body is constantly repairing damage. So this new paradigm for designing materials, not just to be strong and stiff or electronic or magnetic, but actually to be able to understand their damage and then deploy mechanisms.

It's kind of the next stage. So stainless steel does it kind of automatically. It doesn't kind of know. It hasn't got self-knowledge. But the new class of self-healing materials which are called animate materials will have that ability to know their damage and then deploy a healing mechanism it's a strange idea isn't it that a piece of whatever it is knows there's a problem and then repairs itself yeah it's to do with this kind of class of materials which are sometimes called smart

materials but it's a bit of a kind of tricky definition because what it means is that these materials respond to something and in this example we've been talking about responding to damage but they could do that because they respond to for example when a crack forms in that material suddenly now light can get into that material and the air can get into that material and moisture can get in. And so you can design a material that when a crack forms, it reacts to those stimuli, the moisture, the light, and that triggers the sense, if you like, that it's been damaged and then it can trigger a reaction that could repair that crack. So it's about kind of sensitivity to the environment

forming a useful reaction. Does that seem sustainable, though? Well, it's completely sustainable, because the thing is, at the moment, almost all of the money that goes into roads, 95% of it is repair. So we're constantly repairing roads that are falling apart. Same with the rail. Engineering works, anybody? Like, it's constantly falling apart. But that costs money, costs energy.

Almost all of our effort as a society is keeping the existing infrastructure going and it's tiring. What we've been doing so far as material scientists and the material culture is go, we're going to build things and we're going to try and make them last as long as possible, but it never works. I don't know if it

chimes with consumerist culture though, is it? A building lasts as long as you want it to. I don't think people want buildings that last forever, do they? You want to be able to build a building and then 50 years later tear it down and build a different one in its place are you worried that this self-repairing thing might mean that eventually the building or dual carriageway becomes sentient and it refuses to be knocked down and we begin to become a level of empathy towards the sentient dual carriageway or suspension bridge. I think it's one thing to teach a dual carriageway

to rebuild itself. I want to know when we're going to find a way to teach an underpass to love. And if you'd like to buy his new album of electronica in his head, I would love that. How can you teach an underpass to love? A phone call from Gary Newman, he'd like to buy the rights you spoke about designing a material could you speak a bit about what that entails now in

we talked about this serendipitous design of materials but a modern material scientist how do you go about designing a material there's various. One really popular way at the moment is called biomimicry, which is where we look to nature, for example, wool, right? A natural material that has loads of properties that we want. And we try and work out how does it do it? What's it made of? And the brain of a material scientist is about zooming all the way into the atoms and seeing what type of atoms they are, how they're bonded together, and then zooming out just a teeny tiny bit and then looking at the molecules of those materials. How are they structured together? Are they in a very, very neat array or are they all

jumbled up together? Are they bonded stiffly together or is it a little bit more loose? Zooming out a little bit further and seeing are there any textures in those groups of atoms and then zooming out entirely and saying okay so with the knowledge of how this material is built from the very tiniest of scale what can that tell me now about why this is strong or tough or flexible or biodegradable evolution by natural selection produces these remarkable things but i know we were talking earlier mark about the idea that you can use that sort of synthetic evolution to have the materials designed themselves so yeah we have these things called 3d printers now and we can basically layer materials and make new materials by layering them

in different combinations and so a lot of the time we use theories to make the material we want to make and we have a particular idea of it. But a different way to do it is just have a computer control that 3D printer and say, OK, you've got these 10 materials you can combine in any way. Now, off you go combining them. If one of those materials can do some function, which we're going to test it on better than the next one, we'll reward the algorithm.

So we use a sort of artificial intelligence algorithm to keep feeding back into the system. these materials get produced and tested produced and tested produced and tested it's constantly saying okay that worked i'll do a bit more of that that worked i'll do a bit more of that and if you keep doing that you have artificial evolution on a 3d printer and potentially you can sample a whole load of material property space that you might not actually have thought were possible and discover something completely novel because it sounded quite sinister and you said that you were designing one that the reward was if it moved yeah so designing material that can move but we check if it can move by seeing how far away from the 3d printer it's got once you printed it and

does that sound safe that sounds spooky to me we don't have to worry about these sentient dual carriageways at all, do we? This is far more imminent. It's a remarkable idea. What is happening? How can a material, which is just a, you know, we're talking about something like stainless steel, but a very advanced version of it.

How can that move of its own accord? What's happening? So there are materials that are called actuators, which under certain conditions, like a temperature change or changing humidity. So a pine cone is a really good example like they'll open up or they'll close depending on the humidity and the temperature and yeah so it's a natural process but they move and you see this in the natural world all the time but we can 3d print materials that do that and then we can measure how much they move under different conditions and reward that and so as you reward

it and change the formula for that material, it will get better and better at doing that to the point where you could just leave it for a year, come back and hopefully, instead of having to open the door to the lab, it would open the door to the lab. Mark, the word hopefully is doing a lot of heavy lifting there. This feels awfully like... People do get disturbed about these ideas.

And I sort of have two reactions to it. One is that's what the natural world is already that is how we came into being so you're denying your own nature ed by flying at this in that way no no no we are that thing and we are pretty destructive but as we said and now we want to invent something that's also going to do it but these ones might be kinder it's only might be hopefully and might there's also the idea that 3d printing is a remarkable technology isn't it and not only in developing materials as you said and producing components for machines but components for us so at first when 3d printing started to become big people like well let's not just print stuff let's print cells because we're made of cells and could we make an artificial kidney or

liver and then you know we know there are long waiting lists for these things so is that not possible and the first experiments in that direction sort of failed because cells don't like being printed it turns out and they sort of die and then people discovered a much better way of doing it so you print a kind of scaffold, a hollow material, which has all the things inside it that cells like to live in, like a little house in a way. And then you put stem cells from a patient who needs a new liver or a new kidney or some new cartilage.

And then you create the additions in a bioreactor for them to then inhabit that scaffold. And of course, because you can 3D print the scaffold into any shape, that means you could print a nose or an ear or a liver or a kidney and because it's their own cells when it's grown to full size in the bioreactor you can implant that in the body and these people are already doing i mean this is already happening so how do we get the actual material which you know the idea also that it would not be rejected the idea of such a perfect repetition of what was in your body that seems to be i can understand the shape and the texture and all that but the actual repetition of something which would not be rejected seems to be

an enormous leap so if we think about the stage that mark mentioned about when you put the stem cell in that stem cell is sort of a little potential ball that could turn into any cell that we want it to. How do we tell it that when we've printed the shape of a liver, that we want that to be a liver cell and not an ear cell in the shape of a liver? We don't want a liver that behaves like an ear. So how do we do that in the body the way that it does it is the cell recognizes the environment around it so it's sitting there and it's like right okay what can i see what can i feel what chemicals are around me in my little environment and based on that the cell becomes a nerve or a liver cell or an ear cell And that's exactly what we would do in that 3D printed version of it. You would print the scaffold so that the cell, when it goes in there,

finds a familiar environment that feels like a liver, and it would then become a liver cell. And because it's from that patient, the stem cell's from that patient, it behaves in that way. It has the DNA, it has the makeup of the material from that body so then when it goes back in the body's like oh hey friend so it is literally you yes basically and you're sculpting that into i'm just imagining a doctor now saying i'm sorry but the liver we thought would grow in your body has become an ear.

On the upside, we know exactly what the toxins in your body sound like. A break. We've spoken about medical applications in buildings and roads and so on. One of the other great challenges we face is energy. And so can you speak about the advances we're making today in materials science that may help us to address the storage generation distribution of energy? Anna? Yeah, we're looking at sustainability, right? What we want is a sustainable way of being able to

make energy. My own area of research was in hydrogen. And until about two months ago, at the time of recording, nobody really cared about what solid hydrogen would look like or what it could do or what would happen to it if it fell into the hands of an evil genius. Then the movie The Glass Onion came out and suddenly some people wanted to read my PhD. They didn't. They still don't. Can I just check this isn't a spoiler? I've not seen it yet.

This idea of a way of storing energy, that's kind of one of the key missing links at the moment in terms of being able to access a truly sustainable energy system. What I've been interested in is how materials can help that problem. And one of those is solid hydrogen, as the glass onion would say, or as I like to say solid state hydrogen storage materials and these are chemicals these are materials that you can make jackets out of where it contains a lot of hydrogen the reason that we would want to access hydrogen as an energy

source is that it is very lightweight as a gas and there's a lot of energy if you happen to blow it up and so for material scientists we're like huh okay could we kind of stabilize it right if it's a gas let's turn it into a material into a solid state and so what I was in the business of was finding these materials that have a lot of hydrogen in them and working out could you create a kind of power system where you have this solid hydrogen. And it really is a battery technology in the sense so you would release the hydrogen, for example, by heating it up. And then how would you refuel it?

Would you go to a fueling station, essentially put hydrogen in and then it reintegrates itself into the crystals? That was one of the key setbacks in my research. The one that I was working on was called ammonia borane, and it's basically a one-way reaction. So you end up with a kind of molecular mess, which is quite hard to scrape off of test tubes, it turns out. And then it's quite an involved chemical process to get it back into its original form. So although that was a chemical problem, then becomes a bit of a human problem,

because if you say to someone, right, I've've got this amazing car here's a solid hydrogen pack I'm going to give it to you there you go off you go drive 400 miles and then when you're done if you could kind of give that messy molecular soup back to me I'll take it back to my factory and do this big involved chemical process and then I'll give you a new one but so you have to swap the batteries out basically physically take them out and put new ones in yeah just to finish then I'll give you a new one. So you have to swap the batteries out, basically, physically take them out and put new ones in. Just to finish, if I could ask you, your dream material or something you can see on the horizon.

Dream material are playing Glastonbury. Along with molecular mess. Something you think is physically possible at some point in the future. I think I'll go for the invisibility cloak, because it's possible. In fact, there's demonstrations of it in labs. And the trick is to turn a lab technology, which at the moment is mostly in the microwave, so it's invisible to microwaves,

which perhaps is not what we mean by an invisibility cloak. What we mean is there's someone coming down the road and you go, boom, and they can't see you. And that is what we all want, right? That ability just to be not seen at any moment in your life that you don't choose to be seen. Don't you find that once you hit 50, it just kind of happens? Those are made out of something called metamaterial. And so a metamaterial is a material made out of ordinary sort of building blocks of atoms,

but they're arranged in a way which does something extraordinary that essentially, in this case, bends light through you or around you and then puts it out the other side with exactly the angle that it came to hit the front side. And so those materials exist. And sometimes you look at kind of military technology, which almost always seems to kind of go ahead where there's more investment. You think, of course the military are going to push that.

Of course it's going to happen. I do think that invisibility cloaks are going to happen and it will be quite an amazing moment when they are every day. Though most of us will have no idea. I'm afraid I'm going to go back to jackets because one of the big problems obviously that we have in society and materials is the amount of waste that we produce and that sort of disposability culture that throwaway culture is something that we really need to

obviously change. So what I'm interested in is how can we use materials to sort of change our behaviours and to value the things that we have more. What I'm envisaging is a jacket that adapts to the temperature outside and adapts to your own body temperature so that you can have one jacket for the rest of your life. It would have Gore-Tex on the outside. your life it would have gore-tex on the outside and when it's cold like it is today the material would be able to sense that and it would react to that temperature to expand and become really fluffy and insulating and warm then when you get on the victoria line it senses that you're at the center of the sun and so it senses that and then becomes less insulating we then only need one thing right that is very very useful and kind of encompasses all of the needs that a jacket needs to be that's the future that i would like to see that i'm excited about is material scientists

coming together with designers to solve human problems that then impact our environment i love the fact that you have obviously gone into this world and become such an expert on it because when you were a child you had some awful itchy jacket i'm gonna change this world i mean it would change your hiking wouldn't it ed as well this kind of uh the thing is the jacket would still be the same weight wouldn't it despite whether it's warm or you know not that insulated it's still the same weight and when you're hiking long distances weight is an important consideration

Sorry I thought we'd found your utopia I don't want utopia I want more gear, not less The idea of saying you'd only have to have one jacket for the rest of your life that is a nightmare scenario I want every single jacket for the rest of your life, that is a nightmare scenario. I want every single jacket for every possible consequence.

But I was going to say, you might not like the look of it, but then it could be an invisible one and then it wouldn't matter, would it? Or it could change colour. See, the invisibility cloak, I get the idea, but the idea of a military use

of an invisibility cloak would only be in, say, a military situation where the other side will be using radar where even if they can't see you they can still sense that you're there so the ability to appear that you're not there from a visual perspective i don't think it's ever going to be useful to the military they are interested because you can make it invisible to things like heat as well so you know

at the moment you have these heat glasses that will spot at night but this will actually it won't show you as hot it will deflect all forms of detection it'll be all right why is it because i used the word in my original question i said what's your dream and your dream is to create invisible soldiers why i know i was halfway through my dream and i suddenly realized how much the military like this i think that the materials that are marvellous and extraordinary are on the horizon, and how we use them is obviously up to us as a society. I mean, all materials can be used for good or evil,

and I think that the invisibility of heat is really going to be important as the world gets hotter, right? It could be a really great cooling mechanism for buildings if you can get heat to go round buildings as a result of having an invisibility shield round them. them so you wouldn't be able to see them to gain well hang on this is turning into the moral maze this is i mean it's a lovely idea i think we were being overly optimistic considering we still haven't invented car paint that doesn't dissolve under bird shit one step at a time.

But the birds wouldn't be able to see your car. No, I don't know. I love finding out about someone's journey today, and I've just found out so much about yours, Ed. Bird strike on the M40. So we also asked our audience a question, and today that question was, if you could invent a material with a special property,

what would that property be and why? I like David's suggestion. David Hastings said, my D-REAM material, so it starts off well, would be something for Robin to use to keep his youthful good looks as similar to that clearly used by the professor. Youth wouldn't suit me. Ed, what have you got there? Well, Karen Richardson has suggested, she says,

I would like a material with rejuvenating properties. Youth wouldn't suit me. Ed, what have you got there? Well, Karen Richardson has suggested, she says, I would like a material with rejuvenating properties. I think Brian has already discovered this. But Robin clearly puts his on inside out. I think if one of those two makes it, it's definitely going to be that one. I think she would want me to mention that she then has put in brackets, love you, Robin, and a little kiss emoji. Oh, it's fine.

I have no delusion about the fact that I look like I'm 70 years old. It's absolutely fine. You are, mate. It wouldn't suit me to have a young person's face. It just wouldn't hang well with the cardigan. I don't think I know anyone who has aged as much as you have since I've known you. No, no, no. And I know people who are dead now. Yeah.

Let's never book Ed again. Anyway, we've got from Bob has, my idea is a variation on the emperor's new clothes. I would like to invent a cloth that would become transparent if the wearer told lies. It would be compulsory for all politicians to only be able to wear clothing made from this. I think the reason is self-explanatory.

If we couldn't literally see through their lies, we would at least be able to see through their clothes. Sick bags would be provided. Just think of the possibilities if everyone was clothed like this. Surely, I'm sorry, but surely if you're going to have clothing that indicates that the wearer is lying, you want pants

that go on fire. So, there we are. Thank you very much for answering those. Thank you to our panel, Mark B. Adolfny, Anna Porzheyski and Ed Byrne. And Brian, what are we doing with the next week then? Well, this is the end of the series because it's the end of the financial year. And as you've probably noticed, this is the third series this financial year.

So we'll be back with our next series very early in the next financial year. Right, it's not the funniest end that we've ever had to the show, but Brian insisted that we have an end of the series that was fiscally accurate, and it is. It's good accounting practice. It's true as well, by the way. We can't make any

more until the next financial year. I kind of feel that you, for some reason, you've had to say that for some dodgy tax evasion. Yeah, yeah. I don't think the series is going to end. It's going to end in a lengthy conversation about various different litigious issues,

which will be visible to some, but others will see it in plain sight. Thanks very much. Bye-bye. APPLAUSE In the infinite monkey cage Without your trousers In the infinite monkey cage Turned out nice again. Are you confused about why your mortgage rate is going up? Unsure of what causes inflation?

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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. As women, our life stages come with unique risk factors. Like when our estrogen levels drop during menopause, causing the risk of heart disease to go up. Know your risks. Visit heartandstroke.ca. www.mississipi.org