The Recipe to Build a Universe

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Hello, I'm Greg Jenner, host of You're Dead to Me, the comedy podcast from the BBC that takes history seriously.

Each week, I'm joined by a comedian and an expert historian to learn and laugh about the past.

In our all-new season, we cover unique areas of history that your school lessons may have missed, from getting ready in the Renaissance era to the Kellogg brothers.

Listen to You're Dead to Me Now, wherever you get your podcasts.

Hello, I'm Robin Ins.

And I'm Brian Cox.

And in a moment, you're going to be hearing me saying, hello, I'm Robin Inks.

And I'm Brian Cox.

Because this is the longer version of the Infinite Monkey Cage.

This is the podcast version, which is normally somewhere between 12 and 17 minutes longer than that that is broadcast on Radio 4.

It's got all the bits that we couldn't fit in with Brian over explaining ideas of physics.

I do object to the use of the word longer, though, because that's obviously a frame-specific statement.

Yeah, we haven't got time to deal with that, because even in the longer version, we can't have a longer intro.

Can we just let them listen?

I've got an idea.

Can we just have a podcast version of this intro to the podcast, which can be longer than the intro to the podcast?

And then we can have a podcast version of the podcast intro.

We can't get started by now, but if you're still hearing this, I don't know what's going on.

Then we can have a

podcast version of the podcast, and then it would do a podcast version.

Hello, I'm Robin Ex.

And I'm Brian Cox.

Throughout our 14 series, we've always tried to be at the forefront of scientific revolutions and also contentious theories.

And today is no different.

For centuries, it's it's been commonly believed that the structure of little girls is primarily sugar, spice and all things nice, while boys are predominantly genetically made of slug snails and puppy dog tails.

But the latest research from Norway is suggesting something very different.

So

it's not far wrong actually.

Because we're all made the same ingredients to get recycled a lot.

So there's a high probability that the protons or carbon atoms in a puppy dog's tail would have got recycled.

When you buried it in the garden before you were born and then then it grew into some asparagus plant or something, and then you had to go.

Hang on, sorry, can I stop you there?

When you buried it in the garden before you were born, yet again, a physicist who goes, of course, the nature of time is very malleable.

So, tonight we are going to be talking about: well, there's antimony, arsenic, aluminum, selenium, and hydrogen, and oxygen, and nitrogen, and rhenium, and nickel, neodymium, nepotunium, germanium, and iron, americium, and ruthenium, uranium.

And there's others too, aren't there, Brian?

Lanthanum, and osmium, and astatine, radium, and gold, protocinium, indium, and gallium, and iodine.

Iodine, thorium, thurium, and thallium.

So, we don't have time for that.

So,

what are we going to do, Brian?

Ah, well, we're going to look at what you need to build a universe.

What are the ingredients and how are they put together?

And so, to join us, we have a panel, and that panel is

Professor Andreas Heyla from UCL.

I'm a chemist, and if I were building a universe,

I would make it out of mercury, because that way it would be beautiful.

I'm Lucy Green, I'm a professor of physics at UCL.

And if I was building a universe and I could use only one element, I would use helium because then you have everything you need to make stars and party balloons.

I'm Rufus Hound, I'm the professor of nothing anywhere.

And if I was making a universe out of only one element, I'd use iron because then I would be Iron Man.

Although, disappointingly, I'd be married to the Iron Lady and I just don't like those politics.

Can I just say no one has delivered their introduction more as if they were behind a screen on blind date?

I G.I.

And this is our panel!

Andreas, sorry, we'll start with you.

We're going to start with a definition.

So how would you define an element?

What do we mean by the elements of the periodic table?

Well, I think the best way to define elements is really by analogy.

If you think about going into a library and thinking about all of the possible books and encyclopedias and so on, they are made up of fundamental units, and you can work your way down from paragraphs to sentences to letters.

And eventually what you've got are, in English, 26 building blocks, right?

The letters of the alphabet.

And so the elements are really the fundamental, well, now 118-ish

units, sort of ideas elements that you make up the whole world for.

Ish.

Ish, because yeah, I mean actually naturally occurring there's only about 90 or thereabouts.

We've found more of those but they're so short-lived that they don't really count.

And the building blocks of those elements are?

The building blocks of those elements, of course, you know, we can go down to protons, neutrons, electrons.

You can go down beyond to things that you know how to spell like quarks.

So yes, what you're trying to get me to say is that of course it's all down to physics.

I think we should bring

speaking of which, Professor Lucy,

we should start actually because we we're mainly talking about chemistry, so we're going to talk about the chemical elements, how they're built, how they work together.

But we should just do justice to the fact that they're made out of smaller building blocks, the quarks.

So they were made in the first minute or so of the universe.

So we thought we'd just give you one minute, which is the time it took the universe, to build the primordial elements, to explain how those elements were built in the first minute of the universe.

Starting now.

So the idea around the Big Bang is that you have this phenomenal explosion where out of apparently nothing, space and time begins.

I mean, okay, maybe we could discuss sports beforehand, but we don't have time.

But in that process of formation of the universe,

it was 10 to the minus 36 seconds for the universe.

Yes, we had the formation of quarks and also electrons.

But in the conditions early on, they were so hot, they don't immediately come together.

But very soon, the particles do start to come together.

So you start to form protons and neutrons and electrons.

And then eventually, after several minutes, you can have your protons and neutrons starting to come together.

So I've probably done that in less than a minute.

I'm probably faster than actually the formation of the universe.

So you're saying you're better than the universe?

Yes, actually, I think I am.

What impressed me was three people laughed when you said, I'd like to have to say what talked about before the Big Bang, what happened then, but we haven't got time.

And then they went, oh, because we didn't have time then.

And the rest of them missed that particular joke.

So well done, three of you.

You're our core demographic, which doesn't bode well for the future of the series.

So we've got about after a minute or so, we've got the two or three simplest elements basically.

We've got hydrogen, single proton, helium, two protons, two neutrons, a bit of lithium.

That's right, so a small amount of lithium.

And what's really interesting is that, yeah, those processes that happened in the early universe set up everything we have today.

So that the universe by mass is mostly hydrogen, and then you have around 25% helium.

A little bit of lithium, like you say, was formed, but nothing else.

So, very, very

primitive building blocks of the universe.

Before we get to the ingredients of the whole universe, then, for an average member of

the what are the ingredients of our audience members, for instance?

Or what are the ingredients of Rufus?

How many, when we look at a periodic table, if we're ticking off going, yep, got, got, got, got, what are those bits?

Well, it really depends on the asparagus that you've been eating in your garden.

But that's really at the kind of detailed level.

I mean, certainly you've got a lot of hydrogen and oxygen in you.

Of course, there's an awful lot of water.

And your sort of framework is

calcium and phosphorus thrown in with lots more oxygen.

And then there's all the sort of flesh and blood stuff that we've got to throw in.

And there you're going to find a lot of carbon, hydrogen, oxygen, and nitrogen.

And then there's loads and loads of trace elements.

And those are the ones which I think are really quite interesting because those are often the business end that keeps things ticking over.

So sodium and potassium, which runs your nervous system.

At the same time, you're going to have lots of sulfur.

And then transition metals, sort of things like iron, molybdenum, zinc, copper.

And those are often, I mean, along with the sodium, potassium, a lot of that is to do with being able to transfer electrons and protons, right, and being able to shuttle those around as you do chemistry.

Could you just, just so we can picture this?

So we're talking about the periodic table of the elements.

So you mentioned the transition elements there.

Could you give, it's your turn for the one-minute summary.

So the one-minute radio picture of the periodic table?

So the periodic table really consists, I would say, if you wanted to picture it in your head, of three main sort of rectangles.

There's one on the left-hand side, which are the elements that I think most children of all ages want to get their hands on.

Those are the things that you want to throw into water and blow up.

The alkali metals, that sort of stuff.

I brought one.

That's the cesium over here.

Are you going to throw it into your water?

I could throw it into the wine glass here.

It'd be rather expensive, and the program would end.

So maybe we'll do that after the microphones go off.

So what happens then?

So if you put that in the wine glass there, take it to what exactly is going on chemically.

Oh, well this gets really interesting.

If you drop it in there, then one of the things that happen is that immediately electrons start to leap off the cesium and they jump into the water.

And as they do so, there's a positive charge that builds up on the cesium, the lump of cesium.

And the positive charge all goes out onto the surface.

And this makes this bead of cesium incredibly unstable.

unstable and within a few milliseconds the whole thing detonates and you get an exceptionally loud bomb.

No, bomb.

Yes, that's what it is.

Bomb.

I brought it.

I should say

for the listeners at home he's waving around all these ingredients perilously close to each other shouting bomb and looking at his properly.

Trust me, I'm afraid.

I'm a chemistry at the Science Museum.

That was one of your jobs, wasn't it, Rufus?

Yes.

So did you used to do these kind of experiments?

Because it's what all kids want when they get into chemistry.

You want to see the bangs and flashes.

Yeah.

Although not as much as you might, well, I say as much as you might like, as much as I might have liked.

We blew up quite a lot of hydrogen because it's cheap.

We used a fair bit of liquid nitrogen, which

isn't explosive apart from if you put it in a container and then screw the lid on really tight because as it boils and the

volume that it wants to take up is greater than the bottle, it will blow up the bottle.

But a lot of that's to do with the temperature and the energy that's given to the liquid nitrogen.

So, the classic is that you put liquid nitrogen in like a

plastic drinks bottle, do the lid up, it then immediately pressurizes like to almost bursting point, but the plastic is just about strong enough to keep it in.

At which point, somebody goes, Oh, shame, that hasn't worked, goes to pick it up.

The heat from their hand

is the tipping point of that experiment, and the plastic shards out and slashes their hand and face.

I'm not going to say that there's somebody at the Science Museum who still works there that that happened to, but if you happen to go to the Science Museum and see someone with a big scar on their face, it was them.

Are we supposed to issue some kind of disclaimer at this point?

Because this is broadcast on the school run.

That's the problem.

Yeah.

Oh, no, but

there is, I think, a genuine argument that science isn't dangerous enough at school.

It's true.

You can laugh, but the thing that makes chemists want to be chemists is that at school they saw a grown-up blow something up

and they went, oh, I need in on this.

And now everything's so health and safety that you know you get to a science lesson and you know you're not allowed to even look at a thermometer without wearing goggles and a welder's mask.

And it just feels feels like, oh, yeah, this is more of this, it's all theory.

Whereas I remember our chemistry teacher took us out and did a thermite reaction

and another reaction where the point was that the energy in food comes from

the hydrocarbon chains.

So he couldn't, he wasn't by law allowed to tell us what the experiment was or what the secret ingredient he had used was,

but it smelt of candy floss after the experiment was done.

So we went, well, it's sugar, right?

You must have used sugar.

And it was those things where genuinely a group of students working something out

because a big explosion, a big exciting explosion, happened, and then we were all really keen to know more.

Whereas just saying, were you to do this theoretically, an exciting thing might happen, were you to understand it, is like the fast-forward button to don't care, mate, jog on.

It's the same with biology, isn't it?

It's all very well looking at the insides of a frog in a line drawing, but finding them in your pocket, placed there by some other awful boy, really is a far greater education, isn't it?

Yes, I would imagine so.

But that would fall under the auspices of the Natural History Museum, not the Science Museum, and therefore I don't care.

Oh, okay, fair enough.

Andrea, perhaps you'd just describe, because that that you mentioned earlier that basis of chemistry, which is basically electrons jumping around.

Could you describe the

structure of the elements, the structure of the atoms, and

why, what what it is that you look as a chemist, how you describe such a reaction.

Let's say you drop the cesium into the water.

What's happening?

Well, the key thing about chemistry is that chemistry is all about the electrons, in fact, all about the outermost electrons.

And you can think of an atom, in a sense, as having this very, very hard kernel in the center, the positively charged nucleus.

You then have these diffuse layers, onion-like, of electrons around the outside.

And it's the outermost ones which are the ones which really are involved in doing the chemistry.

So sometimes, I mean, it worries me that people say, oh, you know,

it's not possible that life could have sort of emerged spontaneously because

we keep being told about this particle theory of matter, that there are all these dancing particles doing random things.

And chemistry is very far from random.

I mean, the moment you bring a carbon up to an oxygen, for example, and you link them together, then suddenly the way the electrons are distributed is very unsymmetrical.

So the oxygens are negative, the carbon is positive, and suddenly now if you have two of those together, they will come together, you know, repelling and attracting each other in particular ways.

And so the outcomes become in some ways predictable, but also much more interesting.

And you can start building stuff.

And amongst the things that you might build, and this really demonstrates, I think, the superiority of chemistry over physics, is this stuff, right?

Is that you can take those building blocks

and you can make fart goo.

I mean, come on.

That is actually the sound effect they use on the archers when they have that incontinent cows episode, isn't it?

That is, you are in charge of the fart goo.

The very one, yes.

I mean, I get big consultancy fees.

So this is just because there is going to be a change apparently in terms of in school education where there's going to be the actual practical side, the blowing stuff up, the making font gooey.

How important was it for you when you were actually first learning about chemistry to be able to get, well, properly get your hands both dirty and blistered?

Well,

I was never really into the explosives nutter side of things.

But one of the things that really got me into chemistry was a teacher who, when I was supposed to do a practical where you had to identify what was in the tube, said to me, have a sniff and you'll know what it is.

And so,

and he opened up a whole kind of universe of things.

And then I sort of went beyond that and I thought, well, what do they taste like?

So, first of all, I decided that

I would taste the acids in the lab.

And that's when I realized that what chemists call dilute acid, It's 0.1 molar in the mouth, it's not dilute.

My teeth were rubby for weeks after them.

But they all tasted very distinctive.

So then I moved on to the salt.

How are you alive?

Because every time that I see you do any demonstrations, there's definitely a bit where the people at the back go, he didn't put that on the health and safety form.

But the idea of just tasting those things, that level of adventure.

of really and we should say genuinely that we've never had to say this on the show in 14 series Don't do anything, Andrea says, but we've never said about, I mean, literally anything.

Some of it may sound innocuous, but I imagine there is still a chance that you will either kill yourself or your puppy.

Or

you will develop a lifelong fascination with science, so maybe you should.

But that is the point.

A lot of them won't.

Now, I know you're looking from a Darwinian perspective here.

No.

Some of them will be strong enough to survive as chemists, but most of the potential chemists will die.

But isn't that, that, that i think is why chemistry is the funnest of the sciences even if it's not the purest or whatever else is that chemistry's history is of people who went i wonder what that is give it a sniff bite a chunk off it like the reason mary curie died of what she died of when she died was they were like i wonder what radioactivity is bring loads of that ash here and just stir it up in a big pot no idea what it was at all and and the early um descriptions of all the different elements do include smell and taste.

That's how you knew what you were getting.

But Mary Curie didn't lick the radium.

She had a rule: I will glows make a husband lick it.

But I would bet a pound to a penny at some point, Mary Curie went, I wonder what it tastes like.

Because they just lived in a time before the knock-on effects of that were, you know, particularly considered.

Mercury, which now, if a thermometer breaks, you have to evacuate a whole school and like, you know, warning sirens go off.

I was at school, and you used to be able to play with it in your hands and poke around with it.

I think the early aspects of all kinds of science were about human experimentation.

We always started on ourselves, whether it was physics, chemistry, or biology.

And I can think of experiments that were done even in the mid-1900s, where following the Apollo astronauts' flights, where they had flashes of lights in their eyes, even when they closed their eyes in the darkness, they saw these bright flashes.

And they wanted to investigate what was causing them.

So they surmised that it was high-energy particles moving through the retina.

And to test this on the ground, they set up beams of high-energy particles, and people stuck their heads in front of them.

We were talking about this.

I want to we should just investigate.

I want to deviate back onto the subject in a second.

The history, we want to talk about the history, but first, I thought we've talked about the origin of the chemical elements,

the first three or four lightest elements in the Big Bang.

So, Lisa, you're a solar physicist, so you deal with the way that stars shine, which is by producing heavier elements.

So, could you outline what's happening in the sun and how stars build those elements and construct them?

So, perhaps one thing to raise is that temperature is important.

So, actually, when we talked about the Big Bang, the fact that cooling happens means you start to be able to bring particles together and they stay together, so they don't have enough energy to separate away for themselves.

Energy and temperature are the same thing.

And when it comes to understanding stars, you're right, we want to know how stars shine, and that was really the origin of starting to understand how elements are formed.

And I think that the most important process is the one that takes the nuclei of hydrogen and turns it into the nuclei of helium.

So, this is the basic process that is powering most of the stars that we see in the night sky.

So, stars live out most of their lives on something called the main sequence, and during that time, you're bringing together protons, which are the nuclei of hydrogen, and turning them into the nuclei of helium.

And actually, it's a really interesting process that the particles go through because it's not just a case of just bringing them together and off they stick.

You've got to have the right energies, and in fact, more than that, you have to bring in quantum mechanical effects because actually the energies inside of stars aren't quite enough for this process to happen.

So, it is a fairly rare process.

But overall, step by step, you can take protons, you can bring them together to make what's known as deuterium.

You get some other particles and energies come out in the forms of neutrinos or perhaps gamma rays later on.

Then you bring together these deuteriums, you bring in another proton, and you start step by step to build up towards a nucleus which is then two protons and two neutrons, and that's your helium nucleus.

And that's the fundamental process that's happening across the universe.

So, when do we start?

I mean, historically, seeing you know, what the ingredients of the universe be, you know, might be one probably going water, earth, air, fire.

At what point are you going what the building blocks, you know, the Democritus idea, the atomic idea that there are a variety of different atoms?

When do we start getting the first inklings of that story?

So, what, in terms of the history of science?

Yeah.

Ah, so

the early work around hydrogen to helium was played out by Hans Bethe.

So, that was in the 1930s.

And in his paper, he didn't look at anything further on, but the inklings were there that actually this is a process that could build hydrogen to helium, perhaps you could build other chemical elements as well.

But at that time, it's perhaps worth remembering that we didn't have the same understanding of the universe as we have now, and it was still thought possible that the Big Bang could create all of the elements that we see in the universe.

And really,

we need to enter a scientist, an astronomer, called Fred Hoyle, who was anti-Big Bang science.

He was a steady-state scientist, so he thought that the universe, even though it was expanding, was generating new material so that actually overall the density of the universe didn't change.

Because he was looking for ways to discredit the Big Bang theory.

And he was thinking, well, actually, one of those ways is to say maybe stars make the elements.

And he started to look then into the physics of how you could build onwards from helium to get to the elements we see today.

So you go on from helium to carbon, nitrogen, oxygen, then you go on again to magnesium, silicon, and so on and so on and so on.

But

you had to have the physical building blocks or the physics knowledge

which started with beta to be able to put that together.

It's a terrifically complicated process, isn't it?

Actually,

the building, the generation of carbon, the building of carbon, and then the building of oxygen.

It's almost a, it looks fortunate that those elements exist in the universe, doesn't it?

It's such a finely tuned process in stars.

It is, you're right.

So there's, it just happens to be that the forces within nuclei and the electrostatic forces around these charged particles just seem to be finely tuned so that you can get elements like carbon forming.

And in fact, Fred Hoyle was key in our understanding of how carbon forms.

And today that's the most important element for us.

This is the element that life requires.

But at the time when Hoyle was beginning in his work, it wasn't understood how you could form carbon in the stars.

So they had a process where you could bring together three helium nuclei, but it was a really slow fusion process and had a very low probability of happening.

Whereas when you looked at how much carbon was in the stars, clearly there was something that was making lots of carbon.

And so Fred Hoyle realized that actually perhaps you could bring together a beryllium nucleus with a helium nucleus and fuse these together and came up with a new fusion process to explain the formation of carbon.

Isn't that wonderful though to go to be trying to disprove something that he fails to disprove and in fact to go on totally the wrong track, but while going on the wrong track, to create something marvellous in terms of understanding of the universe, I think it's brilliant.

And Fred Hoyle was ridiculed for his support of the steady-state universe, but in fact,

by going against Big Bang theory,

he tested people and he critiqued the work, and people had to really develop their ideas and be robust in their science.

And so, even though he wasn't correct in his ideas about the universe in that sense, He led to huge developments in science.

He's also got the chemicals.

Where is the whole history of chemistry?

Is

largely a lot of the material science work that was done historically was done by alchemists.

You know, they were trying to change base metal into gold.

There was an understanding that there was a process that could bring that about.

Weirdly, if you say that it's just a case of creating neutrons and protons and then allowing the electrons to balance those forms, then actually it's not that far to say, well, if you could just add more protons and electrons and have those be the defining characteristics of those atoms, then you just need to add a few more to get lead into gold.

Well, nuclear physics, that's what that is alchemy.

And I think there are parallels between Newton and Hoyle, actually, because Newton, we all remember him for his work on gravity, amazing discovery, but he was an alchemist, and he had also some very strange ideas when it came to religion as well.

And we've forgotten those ideas.

We just credit him and respect him for the incredible contribution he made.

And I think we should do the same for Fred Horan.

Aren't they deliberately scientists?

Sorry, I'm just interested.

I'm looking at three scientists here.

So, to what degree would you say that is true of the three of you as well?

That you're happy to put ideas out there in the hope that the wrong ideas will be forgotten and

the ideas that you blindly stumble upon being correct are the things that you'll remember.

If I look at the way you were singing them as Professor Larry, Professor Curly, and Professor Mudd,

if I could be polemical for a minute.

I would answer that.

The essence of science is being delighted to be wrong, because every time you're wrong, you learn something.

And Richard Feynman, very famous.

It's always great if you've licked the thing, though, and as you're dying, going, Brilliant, I've been proved wrong.

My innards are burning.

Yeah, it's true.

Theoretical physics is less risky.

You just get the sums wrong, it's not too bad.

But Richard Feynman defines science as a satisfactory philosophy of ignorance.

So it's that philosophy that you start off knowing nothing

and then you play around, and when you get something wrong, you can rule that bit out and move on.

So I think it's central to the scientific endeavour, and actually, it's central to the human endeavour.

But people don't like to be wrong.

In science, you get used to it, don't you?

I'm wrong most of the time in research science, as everybody is.

Well, everybody is

research.

But I'll be less wrong tomorrow.

Yeah, you're less wrong.

But like, that's where I think the cultural shift that,

in no small part, I mean, look, forgive me for blowing smoke up anybody here,

but I think that the mainstreamization of science and scientific ideas has been led in the last few years, in no small part, with the two of you.

And that actually there's a really important philosophical idea which is try today and be less wrong tomorrow, which feels absolutely fundamental to the business of being alive.

And instead,

actually, the cultural yardstick that we hold ourselves accountable to, or we are told to hold ourselves, and more importantly, one another to, is be right at all times, and if you are even momentarily wrong, death to you.

Which is literally the death of all intellectual endeavour, but also cultural endeavour, social endeavour, gender, fluidity, progress of any nature.

If you will be pilloried for being wrong, that is the death of progress.

Yes.

So never put your results on Twitter first.

Just one thing I wanted to say.

You said to the two of us, there are three.

Who's the one are you left out?

And I'd say three.

But, you know,

so I think you're right.

We need people who are willing to put their necks on the line and make bold and creative and completely left-field statements.

Otherwise, science will only ever progress really really incrementally if we all agree, oh, yeah, very good.

Your work, Andrea, brilliant.

I've got a little add-on to that now, and then we just go forward step by step, but little tiny steps.

The really big work that develops our ideas in a really big way comes from people who just take something that seems completely wacky, first of all, you know, general relativity, completely wacky, first of all.

Then it gets tested, and you find observation to support it.

And gradually, we come around to accepting that actually

things weren't quite as we thought they were.

Yeah, at the same time, though, 90% of those completely wacky ideas turn out to be completely half-aft, right?

And

we have to eliminate them.

And yet, it's really important to think

outside the realms of the current possible.

Andrew, we've talked about, we've mentioned the history of chemistry, the history of science quite a lot, but we go back to the periodic table.

So,

what's the first element that was identified?

And how did we begin to say these are things?

There's hydrogen and helium and lithium.

And you can do your little song now.

Well,

the idea of elements had always been around and that there had to be somehow or other building blocks out of which the world was composed.

But it's really in the 18th century that you start to be able to classify things and that there are things which cannot be reduced chemically to anything simpler, is that there are lots of materials which you, you know, if you burn them, you suddenly find that they have a connection with something else.

And so gradually you start to codify this idea that there is a carbon, there is a sodium.

Then eventually,

more and more of these unique components are discovered.

And through the 19th century, you get this incredible race.

And that race is to find more and more elements.

That's how you can become famous.

And so what you're going to do is not only discover it, prove that it's that, and then what you want to do is to put some name to it which will be memorable.

But there was a lot of things that we're going to do.

Please can we talk about Dmitri Mendelev?

Please, can we talk about Dmitri Mendelevier?

We are going to be talking about Dmitry Mendelev.

So, now because Rufus is very excited about the periodic table, and it's kind of, and that is, Dmitri Mendelev is this thing.

So, can we go through just a bit of that story?

So, the periodic table, he's basically starts to fill it in, and as he discovers this structure, he goes, hang on a minute, there's nothing there, but that means that thing does exist, we just haven't found it yet.

Can you give us a little bit of the mystery and that kind of adventure that he went on as he as he created the periodic table?

Yeah, in the 19th century, I mean, one of the things that had started to strike people was the fact that there were similarities between certain elements, and in particular, that they went in threes.

That was the original was a law of triads, that there were three elements that went together.

Now, in fact, the guy who came up with this was a Freemason, and it's possible that the periodic table, at its heart, the original idea, was a Masonic conspiracy.

But leaving that aside,

we can't leave that aside completely.

There are reasons we must.

I recommend reading Alan Moore's From Hell.

Anyway,

by the time you get to Mendeleev, there are actually so many elements there, right, that the pattern is now getting sort of, you know, you now have sort of five elements that you can put, that you can associate.

And

Mendeleev essentially assembled this without really knowing what the rules were.

The only thing that he knew was that things were going to get heavier as you sort of went down, but that then you could group things according to properties.

And the astonishing thing is that actually, you know, he became so confident in his scheme that A, he was able to leave placeholders,

as you've just said, you know, for things that he thought must be there but weren't.

And then in one crucial place

at the bottom of the periodic table, he spotted that iodine and tellurium, that their masses were the wrong way around, but he put iodine under the halogens under chlorine and bromine, and he put tellurium under sulfur and selenium because it was more chemically right.

But he had no idea of what the underpinning ideas were, and that didn't come until this young man, Mosley, in the 20th century, and then quantum mechanics.

Can I, from a layman's point of view, point out why that is so cool?

Is that

A.

Mendelev was a scientist in the old-fashioned sense of wanting to know more and traveled around Russia on the trains that were fresh and didn't spend his time in the first-class carriages but spent them hanging out with the farmers and pointing out why the chemical nature of the soil would lead to better crops for them.

So it was like a really early frontrunner in science communication and the practical applications of the things, of the great wisdom and the knowledge that was spilling out at that time.

So there was that that made him a kind of a renegade figure.

But the other thing was that when he found these lists of

elements, or when he spotted that the properties put them in shared groups, he left these two gaps.

But

what is just so amazing is that at the time,

there was, as sort of exists now, a sense that, but we already know what all of the stuff is,

and therefore, if you've left two gaps, your theory is wrong.

And Mendeleev went, what if we don't?

And they went, but we do.

And he went, but what if we don't?

And within two years,

two elements were discovered.

One of them, gallium, named after gaul,

or the French word for cockerel, which was Gallic, which was the thing of naming...

But there's more to it because the guy who discovered it, his surname was Lecoq, which means the cockerel, the rooster.

So he managed, and he was hounded about this, to get his own name in the pun,

the country he was from, right, all into one element.

So to present a theory with gaps that then allow other scientists to step up and go, oh, hang on, maybe they're like, if you don't present the whole thing as the finished piece and then have your competitors almost validate your theory, that's as good as science gets because it is outside of the

there should be a better phrase for the afternoon on Radio 4 than dick swinging, but I just can't think of it.

Posturing.

Posturing, thank you.

Posturing.

So, yeah, that's

but to have confidence in your idea and then allow for the

ego-wrought posturing of your contemporaries to then force them to actually

chime with truth rather than ego.

That's as good as humanity gets, quite outside of science and whatnot.

But I just like this idea that there's this hairy old bloke travelling around on trains talking to farmers who

forces

the building blocks of the universe to be understood

in a superior fashion.

It's beautiful.

Jade, we talked about the Lucy talks about the building of the lighter elements.

So you talked about hydrogen to helium and then carbon and oxygen.

But when you get to element twenty-six, so you get to iron,

no longer are those built in the simple way in stars.

So we've got a lot of elements beyond that.

So, could you just outline how those come into being?

So, we're talking about common ones: gold, silver, tin.

That's our elements that we see.

Are there tin?

Tin.

Tin is one of the most emotional elements.

Listen, it cries.

Did you hear that?

No.

Make it cry

Shh.

The cry of tin.

So the formation of the elements, the heavy elements.

You're right.

When you go beyond iron, you're looking at processes then that build up the structure but that require energy to be put in.

So everything up to iron, or thereabouts, you can release energy.

And that's the wonderful thing about the processes because that's how you power stars.

You bring hydrogen nuclei together and you release energy, and that powers our sun and many other stars out there.

But once you go beyond iron, the situation changes.

So then you have to think, well, how can you start to build up larger structures, which essentially is revolving around bringing in more neutrons and capturing them into the nucleus of the particles?

And you can do that in stars if you have a source of neutrons along with a process that allows you to transform a neutron into a proton.

So if you remember, the nucleus contains protons and neutrons together.

You can't just keep building in more and more neutrons, you'd build a very unstable particle, but you can transform some of those neutrons into protons and build bigger nuclei.

So, stars could do this if they have some neutrons available, but when it really happens in a dramatic way, you see these elements being formed during a supernova explosion.

Then you have a flood of neutrons and you have neutrinos rushing through as well.

And in those processes, you can build the larger elements, which are absolutely important for us.

So, we're talking about the ingredients for the universe.

So, how much can we be well?

This the planet Earth is a good example.

Then, are we able to monitor things that are many light-years beyond us and go, well, actually, the basics are all here.

We are able to, or is there a possibility that within certain other star systems, within certain other conditions, there are a myriad of elements which we know nothing about?

Well, I think using the Earth as a way to probe what the rest of the universe is made of actually was misleading, first of all, because when you looked out into the universe and you used the fact that there are signatures in light carried in light that allow you to probe what the universe is made of.

So, this is the spectroscopy, and you use the particular colours in the light to be able to say that light is characteristic of this element, and this light is characteristic of this element.

And first of all, when studies began on the Sun, of course, it's our nearest star,

it was the elements that are most abundant on the Earth were found.

So, it was very easy to think, oh, well, the sun is made of exactly the same stuff as we have around us and in the same

proportions.

But actually, that was completely wrong.

Well, in some sense, it was wrong, because what we know now is that the sun is made mostly of hydrogen.

And that wasn't discovered until the 1920s by an astronomer called Cecilia Payne-Goposhkin, who normally people haven't heard of.

But she single-handedly found out what pretty much the whole of the visible universe is made of because she, at the time, was the person who took the light coming from the sun, applied the latest mathematical theories about how temperature affects the light that different elements give off, and realized that actually the sun isn't made of iron, like Eddington thought, or isn't mostly made of carbon or nitrogen or things we see around us, but is mostly made of hydrogen and helium.

And so, I think, you know, when you read school textbooks, you read that Newton discovered gravity, and you read that Darwin discovered evolution.

And I think that Cecilia Paine-Koposhkin should be listed as discovering what the universe is.

It was a huge debate, was it?

Because people think, What's the energy source of the Sun?

And Kelvin, Lord Kelvin, calculated if it was made of coal,

they knew the mass of the Sun, that really, because you're thinking, What is it made of?

They didn't know about nuclear fusion, they just knew about the atomic nucleus just around that time.

And you dropped something familiar.

And it contradicted Darwin because it seemed, I can't remember the number, that was a few, at most, tens of millions of years, I think, that if the Sun, knowing the mass of it, was made of coal, then it could only emit that energy for a few tens of millions of years, not billions of years, which the biologists were pointing to billion-year time scales.

So, if it was made of coal, the Sun would burn for about 6,000 years.

If it was powered by its own gravitational collapse, then you would get tens of millions of years.

But you're right, it's nothing on the billions of years that people were starting to think about evolutionary processes.

It's quite remarkable that we were talking about the

early 1900s here, and it's almost living memory.

That's right.

1920s, we work out what the Sun is made of, and in the 1930s, we finally figure out what the energy source of the sun is.

Incredible.

The sun, you said,

is made of hydrogen and helium.

And maybe this is a slight sidetrack, but noble gases, WTF,

right?

They basically don't react.

They don't do you like.

Oh, yes, they do.

So, hang on then.

Okay, right.

Yeah.

Helium.

Helium doesn't, I agree.

Okay, but

I don't know that.

Oh, I don't understand it.

Does argon react?

Argon does, yeah.

What reacts?

Transly.

I was taught it doesn't.

Transiently.

You can see spectroscopic complexes of argon with things like HCl in the gas phase in the lab.

It's an undergraduate practical.

Really?

But how does that...

How does that mean?

Can you just very briefly, just probably for my own amusement, can you describe what's happening there?

Because argon's got a full outer shell of electrons.

Well, the thing is that the full outer shell of electrons turns out to be a sort of rather simple way of thinking about things.

And it was back in the 1960s that somebody spotted that the energy that it would take to ionize

a molecule of xenon, for example, was very, very similar to the energy it would take to ionize a molecule of oxygen.

And so suddenly they thought, if we can react something that reacts with O2 to give O2 plus, maybe we can do that with xenon.

And what they did was they started reacting with the Tyrannosaurus rex of the periodic table with fluorine.

And so suddenly you can make xenon fluorides, you can make xenon oxides, then they were able to move on to krypton.

And so you can make all of these compounds.

The thing is that the idea of the filled shell is in a sense a construct that we've put on there.

In the end, the electrons don't really care how many electrons, all they're trying to do is to minimize their own energy.

And if takes place by forming a bond to fluorine then that's great and so we can make these things and we can do chemistry

but

that presupposes you know what they are and that you've got some in this mug

so before that point somebody had to say there's a thing here and we're going to call it neon there's a thing here and we're going to call it xenon what i don't get is How in human endeavor did it get to the point where people said in this flask there is a thing?

Yeah, where did it get to it?

It's a great story.

It goes back to Henry Cavendish.

And Henry Cavendish did an incredible experiment at the end of the 18th century in which he passed sparks into a flask full of air.

And what he found was that the nitrogen and the oxygen would react together, and he could remove those by adding water.

And so gradually, gradually, gradually, the volume of stuff that he had went down and down and down and down until he was left with a tiny volume of

something.

But he had no idea what it was.

And there the matter rescued because no one could really work out what he'd done or tried to reproduce it.

And it wasn't until Lord Rayleigh demonstrated, and here, you know, it's a bit like Al Capone, right?

A tiny accounting error was that there was a very, very small difference in the density of nitrogen if you made it by a chemical reaction.

So you mix two things together and you make pure nitrogen.

And on the other hand, nitrogen, if you remove all of the other components of air, so you take a slug of air, you remove the oxygen, you remove the carbon dioxide, and so on, and then you measure the density of that.

And there was a tiny difference in the density of the order of a couple of percent.

And Rayleigh said, This is really strange.

And a man at UCL, in fact, our university, William Ramsey, said, You know what?

I think there's got to be something else in there.

And so at that point, he did the same experiment with much, much more air.

And this time he removed the nitrogen as well.

And what he found was a gas which had a different spectroscopic signature and which didn't have any chemistry.

And so he called it Argon the Stranger.

Okay, here's a follow-up question.

So then, da-da!

Argon.

Argon.

The stranger.

Then somebody goes, oh, I've got another one.

No, no, it's the same guy.

Because William Ramsey then goes, hang on a second, this thing has a mass of 40.

That means that it sits, right, sort of around potassium somewhere.

Wait a second, there's something else here.

Maybe there are others.

And so at that point, there was a kind of 10-year chase where he went hunting around, desperately trying to find other elements that might fit.

Somebody reported to him that there was this, that if you took certain radioactive rocks and you heated them up, they would boil, right, and they would release a gas.

He isolated the gas.

And then the spectroscopic signature was the same thing that had been seen in the spectrum of the sun, right?

That was helium.

In fact, that was confirmed by William Crookes, who was the person who discovered thallium, right, that gave the green line in the spectrum.

And then they found neon and they found krypton and xenon.

Radon came a little bit after that.

And so really the thing is that Mendeleev had no idea of how his scheme worked.

And so he didn't know that there was a whole column missing.

And Ramsey actually filled in that entire column.

And so this is where I was again disappointed with one of the names of the new elements.

And I'm really sorry to Professor Aganessian, who has had his name put on the last one of the noble gases.

But maybe it should have been called Ramzon after Ramsey, who discovered all the rest.

So, we have a final question for all three of you: which is: if you could create an element that would be a real boon for the universe but doesn't exist as yet, what are we missing?

I don't want one element, I want a whole periodic table of dark matter.

Just think a whole new universe of chemistry.

Dark chemistry.

Surely, obviously, the one we all want.

Boom!

It's the element of surprise.

What do you reckon, Lucy?

What's missing?

What's missing?

Well, I like the dark universe, the dark periodic table, but maybe one of the big questions is why we don't have enough antimatter in the universe.

So maybe I would like to see the antimatter periodic table.

Why is it that we have so much matter and not enough antimatter?

Where's it gone?

So

we asked our audience if you could remove one element from the periodic table, what would it be and why?

And these were the answers: aluminium to save Americans from pronouncing it wrong.

The fifth element, because Bruce Willis never improved on his role in diehard.

Whoa, whoa, whoa, whoa, whoa.

Whoa, whoa.

Objection half.

The fifth element is Willis's final hour.

Lilu.

Lilu, Miyajamovich, wearing nothing but Versace.

Get over yourself.

Who wrote that?

It was Dan Benton.

Car park, Dan, car park.

This one is, it says EU Europium 63 because it costs us £350 million a week.

And it's signed Nigel Farage.

Rhenium, because things can only get better by derenium.

Thank you very much to our panel, Andreas Ella, Lucy Green, and Rufus Hound.

While we've been off air, we've had lots of questions, and the one we've picked out of the hat today is from Mark Saunders.

And he emailed us with this: Due to relativity and time dilation, is it possible that somewhere in the universe a star is born and dies in our lifetime, Brian?

It's a good question.

You've got to try and get into a position where time

speeds up for you relative to the star, because stars last.

What are the shortest-lived stars, Lucy?

Oh, I think a few millions of years.

Yeah, so something quite quick.

Do you go to speed time up?

So I think you'd have to go close to a large,

a massive object.

In fact, we did this, didn't we, Rufus, in the science of Doctor Who?

You put a little rucksack on for some reason and then pretended and acted falling into a black hole.

Teetered on the brink of

a

black hole.

Yeah, yeah.

So, actually,

so if you could teeter around close to a black hole or fall into one, then you would see the whole history of the universe actually play out as you fell across the event horizon.

So, I would say go stand close to a black hole.

Do we need to bring that warning?

Please do not go and stand close to a a black hole.

May well affect your length.

So,

thank you very much for listening.

Goodbye.

I think we've got the podcast podcast podcast podcast version of the podcast podcast.

Brian doesn't even know that you have actually now listened to the whole of the show

and this is all he's been doing

for the last 47 minutes.

And it's not going to end for a while either.

It's a nested infinity of podcasts.

This is my life.

You'd just end up with the podcast.

Hello, I'm Greg Jenner, host of You're Dead to Me, the comedy podcast from the BBC that takes history seriously.

Each week, I'm joined by a comedian and an expert historian to learn and laugh about the past.

In our all-new season, we cover unique areas of history that your school lessons may have missed: from getting ready in the Renaissance era to the Kellogg Brothers.

Listen to Your Dead to Me Now, wherever you get your podcasts.