Magic Materials

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Hello, I'm Brian Cox.

I'm Robin Inks.

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 is no give in the cardigans.

These are all questions for material science.

Which materials have changed the direction of civilization?

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 Bieblebrocks, 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 the thing.

That is a very evidence-based intro because everything that I've said there is true.

I'm going to admit this, right?

Our producer said, I've never heard of Zaphod Bieblebrocks.

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 Xaphod Bieblebrocks?

Yes, there we go.

Who here knows what oobleck is, right?

That's still enough people.

Right, Nate?

And they are.

Mark Giadovnik.

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, doesn't it?

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 Projaiski.

I'm a material scientist and science communicator, and my favorite 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 like 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 of bit.

But no, as an outdoorsman and a hill walker, my favorite material is Gore-Tex, invented in the 60s.

They were stretching Teflon just to make it go further and then realized it created air holes, air holes that were big enough to let water vapor out but keep water droplets from getting in.

And that revolutionized 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 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 and 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 the 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.

Yeah, it's just.

So that's what academic study is, isn't it?

Academic study is refining the question until there is no answer.

It's an hour ago for 20 and 30 years.

But it will have been someone who is a material scientist who invented Gore-Tex, not someone who went, well, I know what material is.

You'd have worn their anorack 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, I'm not really an expert material scientist.

Yeah, there is science has 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.

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 indium 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 indium tin oxide is one of the key materials that 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 jumping round?

Or how broad is our definition of jacket here?

So as long as you can make holes for a head and arm

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, but you could.

And that's why you left working for Top Man, didn't you?

Yeah.

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

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.

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.

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 is you're not wearing a jacket.

That's what I'm trying to do.

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 would 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 little 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 and

form an alloy?

There was an athlete who always came third and felt very unrewarded.

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, do you know what?

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 colour

until somebody just got all the paint that was left over and mixed it together and discovered brown.

That was the brown.

Are there any children listening to this?

This is untrue.

I'm lying.

I'm lying for a 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, and I think...

Well, it sounds like you don't agree.

No,

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 it's probably the one it was, a copper alloy rock.

And the next day, in the fire, because they've 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's 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.

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 are so rare that all through that million years it could have happened, it could have happened, it could have happened, 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 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.

Or you have them put on your back, don't you, when you go to that special health clinic?

That is really 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 are 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 result 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 Holomate, 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 happen 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

magician, they would, you know, a witch,

they would just would not believe that steel could be stainless.

Well, surely, just for going back in time, that would prove the job.

That would be a red flag.

Straight away.

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 with this 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 like digital age.

And silicon is kind of a funny 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 flavor 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 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 silicone 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

lives.

That's the difference.

Your silicone is the boob.

And not anymore, even.

So it's saline now.

But

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 was kind of, you know, 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.

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 it 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,

the first thing they thought was: could you imagine playing Dungeons and Dragons with someone who works at CERN?

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 what we know about

the different types of atoms there are.

So there's a hundred odd types of atoms that naturally occur.

I'm not going to sing the song.

Sing the song.

Sing the heavier 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, you know, they have different properties.

And that was incredibly exciting.

And people were 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?

And would that be stable?

Could we make one on Earth?

What kind of properties would it 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 synthesizing unobtanium?

I mean, I think one of the things that I guess material scientists really enjoy is that 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 the grid, because we're pumping electricity through and most of it gets gets lost as resistance.

But if you had a superconductor that had no resistance, then overnight we would 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.

Like almost everything to do with our energy policy and our technology would change.

But no one's found one yet.

And that's the great thing about material sciences because you're always waiting for someone to suddenly announce that they've been beavering away in their lab for 10 years and unobtanium 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 is quite a remarkable idea that a material when damaged can repair 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.

And 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, right?

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 has 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 as a 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, oh, it never works.

I don't know if it chimes with sort of 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 the self-repairing thing might mean that eventually the building or dual carriageway becomes sentient and David refuses to be knocked down, and we begin to have a level of empathy towards the sentient dual carriageway or suspension?

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 hand i would love that how can you teach him the person

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 the we talked about this serendipitous design of materials but a modern material scientist how do you go about designing a material

There's various ways.

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 design 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 to just have a computer control that 3D printer and say, Okay, you've got these ten 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.

As 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.

Yeah, because it sounded quite sinister.

You said that you were designing one that the reward was if it moved.

Yes.

So designing a 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.

Does that sound safe?

That sounds spooky.

We don't have to worry about these sentient jeweled carriageways at all, do we?

This is far more imminent.

But it's a remarkable idea that 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 a change in humidity, so a pine cone is a really good example.

They'll open up or they'll close depending on the humidity and the temperature.

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 for you.

The word hopefully is doing a lot of heavy lifting here.

This feels awfully like people do get disturbed about these ideas.

And I sort of have two.

Oh, I wonder why.

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.

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

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 were 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, is 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 indications 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 people are already doing it.

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 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 recognises 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 cells 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.

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.

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 thesis.

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 materials 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 it becomes a bit of a human problem.

Because if you say to someone, right, I'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, if I could ask you, your dream material or something you can see on the horizon.

Dream material airplane, Glastonbury, yes, sir.

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 into 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 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.

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 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've 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 going to change this world.

I mean, it would change your hiking, wouldn't it, Ed, as well?

This kind of human beings.

The thing is, the jacket would still be the same weight, wouldn't it?

Despite whether it's warm or

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, but 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 for me.

I want every single jacket for every possible consequence.

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 only gets ever going to be useful to the military.

They are interested because you can make it invisible to things like heat as well.

So 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.

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 don't know.

I was halfway through my dream and

I suddenly realized how much the military like this.

I think that materials that are marvelous and extraordinary are on the horizon, and how we use them is obviously up to us as society.

I mean, all materials can be used for good or evil.

And I think that the invisibility of the heat is really going to be important as the world gets 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.

So you wouldn't be able to see them to gain.

Well, hang on, this is turning into the moral maze.

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 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-Reem 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 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.

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.

And I know people who are dead now.

Yeah.

Let's never book head again.

Anyway, the

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 Miadofnik, Anna Porsche, 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.

Well, it's not the funniest end that we've ever had to the show,

but Brian insisted that we had 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 accounts 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.

I don't think this 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.

In the infinite monkey cage.

Till now, nice again.

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