Christmas Special 2015

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Hello, I'm Robin Inks.

And I'm Brian Cox.

And welcome to the podcast version of the Infinite Monkey Cage, which contains extra material that wasn't considered good enough for the radio.

Enjoy it.

Hello, I'm Robin Inks.

And I'm Brian Cox, and it's Christmas Day.

The day where everyone thinks about the thermodynamics of turkeys, the Newtonian dynamics of sleigh rides, and whether cranberries are alive or dead.

Right, well, I'm not entirely sure everyone thinks like that.

Anyway, so cranberries, alive or dead?

Linear superposition.

Of course.

Same with every berry, aren't you?

Every berry you put in a linear superposition.

Absolutely.

You don't see enough of that in Bake Off, do you?

The linear superposition thing.

Have you been thinking?

Because this is Christmas Day, and I wonder whether, because the Schrödinger's perspective of opening presents, is it better not to open the present and it remains in a superposition going, it really is definitely what I wanted and also definitely what I not wanted, as opposed to opening it and finding out it's a dead cat.

Which I have

no idea why my uncle keeps giving me those, but I think he's very tight and he's also a vet.

So, um,

so we have taken a break from attempting to put together our Lego Large Hadron Collider, which is taking longer than we'd hoped.

And we're going to bring you this monkey cage Christmas special because Christmas Day is a very special time.

It is the only day of the year that I can watch Alastair Sims Scrooge without Brian going, Well, of course, ghosts break the first law of thermodynamics and say, say, ni, mi.

Second law and the first law.

Yeah.

Gibbs free energy.

It's going to be negative.

Delta H minus T delta S.

You know what Delta S is?

That's entropy.

So that's a catchphrase from the second series which didn't catch on.

The t-shirt sales not as high as we'd hoped.

You'd imagine watching Ghost with him and a potter.

So

I don't want that.

Today we're talking about the true meaning of Christmas, the Doctor Who Christmas special.

There'll be no spoilers, there can't be because we haven't seen it yet.

And why haven't we seen it?

Because it would require time travel.

And we still haven't perfected that machine, have we?

For over 50 years, Doctor Who has twisted our universe into all manner of shapes, filling our minds with ideas and monsters.

It's introduced us to real and imagined scientific ideas.

It has been a portal creating thousands of sitting-room conversations about the nature of time and space.

So to guide us through the real, the possible and the speculative ideas of Doctor Who, we have the usual panel of a physicist, a comedian, a special effects expert, an author and a member of the General Synod.

Certainly not all the same person.

And they are.

Hello, my name is Paul Franklin and I design visual effects for Hollywood films including Inception and most recently Interstellar.

And my favourite idea from Doctor Who is the Daleks, an enemy so terrifying, all our modern fears wrapped up into one, that we still find them terrifying terrifying even 50 years after we realise they'd be stopped by a couple of steps and a low wall.

Apart from when they're not.

My name is Simon Guerrier.

I am a writer and I write Doctor Who books and comics and audio plays and the scientific secrets of Doctor Who.

I think my favourite idea from Doctor Who is that you can make a living writing books and comics and audio plays from Doctor Who.

My name's Victor Stock and I'm a priest and I was the Dean of Guildford where I first met Brian Cox and we started doing things together.

Even

one of those, he's a cheeky vicar this one.

Even in Geneva.

But since then I've retired and I live in London and my gig is working in Westminster Abbey.

And my favourite Doctor Who thing is quite simple and straightforward at the moment.

And it's the TARDIS.

And it's the TARDIS.

Can I say why?

Yes, you will.

Thank you.

The TARDIS is because it's like Christmas.

Bethlehem is a small place, only religious people think this small stable's got something inside it which is bigger than the universe.

And TARDIS, you get inside this little tiny whatever it is, and everything changes.

The universe might be in.

Oh, that was real proper vicar work.

That was for anyone who didn't make it to a church, other proper.

I was watching the Doctor Who special the other day, and as I looked at the TARDIS, I thought, isn't that a little bit like Easter?

Anyway, so

I don't think we were listening properly, I guess.

But I did like it.

It was very

good with your allegories.

Sorry, continue introducing yourself.

So, over to.

Hello, I'm Ross Noble.

I have no scientific qualifications, and I was turned down for the job as the vicar of Guildford.

But

my favourite Doctor Who idea is the fact that one day I might be killed by a robot, Bertie Bassett.

A muted response there, but a nod from the expert.

Hello, my name is Faye Dauke.

I'm a theoretical physicist at Imperial College London.

My PhD thesis title was Space-Time Wormholes.

I research black holes, the big bang, and I'm trying to discover the deep structure of space-time.

And my favorite Doctor Who item is the TARDIS for a slightly different reason than Victor's.

It's because there are solutions of Einstein's equations for general relativity, in which

space-time has a

portal through which you can go, and inside of which has a certain size.

And inside the space-time can be as big as you like.

You can fill that

region with a space-time with as large a space-time volume as you choose.

There are many different solutions.

They're called

Oppenheimer-Schneider solutions.

And so we don't know whether such solutions are physically real, but the idea of a TARDIS is contained within general relativity.

And this is our panel.

So, Ross, do you think the TARDIS should be renamed the Oppenheimer-Schneider machine?

Well, that would be, well, you know, the fact, you know, the fact that the initial TARDIS actually means something, that's going to be a long, you know, when somewhere, when he gets a new companion, they go, what does TARDIS stand for?

And he goes, what was it again?

The Oppenheimer Schneider solution.

Oh, god, no, I'm dyslexic.

Forget it, I'm not even gonna try it.

Yeah,

what does TARDI stand for?

Time and relative dimension in space.

And what does that mean?

Well, I'm glad you asked me that.

Well, if you're gonna start putting me on the spot, let me just bring up the whole wormhole thing.

Can we change the name so they're called like space wormholes or like time worm or something space, something scientific?

Because everyone's now talking about wormholes, forgetting about actual wormholes.

Do you know how disappointed worms are now?

Because they've read all your books and stuff and they go, oh, brilliant, I'm off down my wormhole, still underground.

They're not popping out on the other side of space.

And it's not fair.

Come on, scientists, think of the worms.

That's interesting because you live in Kent now, don't you?

And that is, of course, not far from where Charles Darwin wrote his book, The Formation of Vegetable Moles Through the Action of Worms, with observation on the habits.

Have you read it?

Theatrical worms?

Yeah.

Well, no, I mean, all worms are theatrical in their own way, aren't they?

Let's not prejudge them.

Let's allow them to do their show and then decide if it's theatrical enough.

It's really hard getting them little top hats on them, though, isn't it?

It just keeps sliding off.

You don't know.

You put it on the wrong end.

Does that answer your question?

Yeah, does it answer?

Not in the way I was imagining, but it'll do.

So, Faye, time and relative dimension in space.

Let's deal with it.

What do you think, as a physicist, here is this was the starting point of Doctor Who, this police box, this police box that can apparently travel through time and space.

And when you hear this phrase, time and relative dimension in space, what do you interpret that as?

I think about space-time, which,

according to Einstein's theory of general relativity, is the arena for everything that happens.

And it's something which unifies both space and time.

And

in a very

in a way that's very beautifully encapsulated in science fiction like Doctor Who, we travel in space-time.

So we don't have now, according to modern physics, a picture of the world as space, and we exist in space with time passing in the same way for everyone and everything.

But we move, we live out our lives in space-time, we trace out trajectories in this four-dimensional arena called space-time.

And that's very much in accord with the idea of time travel.

If we're moving, traveling through time in this space-time arena, why can't we go back?

So it raises that possibility immediately once you think about space-time as a whole,

as a four-dimensional substance.

So, you wouldn't say, so that's starting point for Doctor Who, in terms of science fiction, where sometimes things are just absolutely wonky, totally made up, that's actually not a bad starting point then for a children's science fiction show to have this object called the TARDIS.

Well, time is something which human beings have wondered about ever since.

Well, since we have records of people thinking about the nature of the world, people have thought about the nature of time.

And

certainly, our current view of space-time, our current best understanding of the nature of space and time, definitely lends itself to the notion of time travel.

In fact, people do research on time machines, and in the scientific literature, they're called closed time-like curves.

You have to give them a you know, a fancier, more science-y-sounding name than time machines.

Yeah, you can't call them time machines because you wouldn't get funded.

So, you have to call them

closed-time-like curves, and people really do try to figure out whether the laws of physics

allow such entities.

And

unfortunately, the consensus is that probably not, but we still don't know how to incorporate quantum effects into our understanding of space-time.

So

until we do that, we could still say there's a small possibility that they could be, that they could be possible.

So so Einstein's theory of general relativity permits

those structures.

So so wormholes, space-time wormholes,

permits those at the moment.

And so we have to conjecture that they won't be there in nature.

There are solutions of the Einstein equations that have these closed time-like curves or time machines in them,

and we have to explain or understand whether they're physically allowed in the universe.

So it seems like they're probably on physical, but

we don't have the final answer because we don't know how quantum matter can change our understanding of space-time.

Simon, it could be real.

It's all real.

Come on, remember, this is a geek for money.

He's not going to start getting rid of that payday.

Who's the most scientific doctor?

The third doctor, John Pertwee, is the one who most frequently refers to himself as a scientist.

But that really depends on your kind of tolerance of the plots.

I think

there's lots of big, mad ideas in Doctor Who, but not all of them

make scientists happy.

Sometimes when Doctor Who gets its science slightly more left field from conventional thinking, you get lots of very angry people on the internet.

You've just written a book all about the science of Doctor Who, and in researching that, I presume you have come across what were the ideas that have most angered people within the scientific community?

Well,

there was an episode last year in which the moon turned out to be an egg in which lived a moondragon.

And

what's weird is that that made people cross in a way that an episode a few years ago, a Christmas special a few years ago, where the earth turned out to be full of giant spider babies, didn't bother them at all.

And so, what I found, I think, is that when people have criticised the science, what they mean is that they've criticised a tone of story, or they've not liked a particular story because it didn't,

the logic inside that story didn't work.

So, I think whether the science is right or not is a different question.

And I should just say, for balance, what's the greatest Doctor Who episode?

My favourite is a 1973 story called Planet of the Daleks, in which John Pertley goes to a planet of Daleks.

It's a bit of a surprise halfway through.

And

he defeats this army of Daleks by unleashing a volcano that buries them.

But because the writer wanted to make it a bit more space and exciting, he came up with the most silly idea he could think of, which is that rather than lava, hot lava, it's a volcano of ice, an ice canoe, as he called it.

Sixteen years after that episode was shown, and it was just a bit of sort of fantasy fun really, um Voyager two going past the moons of Neptune took a photo, and we now think that not only do four of the moons in the solar system have ice canoes, but also Pluto.

So, Doctor Who fluked it science.

Now, there are some people who think that if you base your Doctor Who stories or your science fiction stories on real scientific discoveries, then that's proper hard science and that makes the story good.

And in and this is where I think the lie comes, because what that would would mean is that when they made Planet of the Daleks in 1973, it was a silly fantasy story, but now, without anything changing in that story, it's now a proper hard science story.

So that's kind of where I stand on it.

I think the science can be right in a Doctor Who story, and it can still be ridiculous, or vice versa.

Victor, what's the General Synod position on Doctor Who?

I've absolutely no idea.

I mean, the General Synod worries about some things which matter, and it it doesn't give much time and attention to the really essential,

fundamental meaning of the universe, which is obviously science fiction.

And Doctor Who, but I don't quite know why they haven't, and so I'm not very helpful on this, especially on Christmas Day after a very good lunch.

Have you, I mean, things like, for instance, you know, Harry Potter, not from, I don't think, as far as I know, for the General Synod, but

there have been religious organisations that have been very angry about this playing around with kind of ideas of witchcraft and magic.

And I wonder if there has been anything in the history of Doctor Who where, certainly Mary Whitehouse, for instance, you know, she was very angry about, I think, the Tom Baker years, and in particular, some of the Philip Hinchcliffe episodes made her particularly cross.

But she would have exploded by now, of course,

mercifully.

Oh dear, lots of her fans are still alive in Worthing and they'll ring up.

I think an important thing to say as an Anglican is that we don't really go in for this nastiness.

You know, we make friends with atheists and we go on on programmes like this.

And

in our quiet, understated sort of middle-class liberal way, we really get on with most people.

And I think a rather serious thing about this is that in Europe, we have had what we call the Enlightenment.

That was preceded by the Reformation.

The Enlightenment was followed by the Industrial Revolution.

And religious people have had to come to terms with all these things.

And so,

sensible, open-minded religious people are not so frightened about things like science fiction.

And as it's Christmas Day, and which I think is the best day in the entire year because you get people round a table like this who are unlikely to get round a table any other time of the year, you know, the difficult relatives you feel you should invite, and it's so nice when they go.

But

that's the spirit of Christmas.

I think this whole business of being able to meet people who you normally don't meet and be open to ideas that you really haven't got the faintest idea or hope of understanding is a frightfully good thing.

But then that's the Church of England line.

What I love about you, Victor, you seem to be made out of bits of Ealing Films and Dick Emery.

Well, it's a lovely, it's a beautiful monster, the Anglican monster.

That is the Church of England.

Paul, you

mentioned already, did double Oscar winner for Inception in Interstellar.

And when we were growing up, one of the great excitements was seeing on things like the multicolour swap shop, Matt Irving explaining the special effects, you know, very low budget and putting those things together.

How important was Doctor Who in terms of forming the human being you are now?

Absolutely essential.

A long time ago, I was up for a job at the BBC early on in my career.

And

they asked me what had inspired me to get into making visual effects for films.

And I told them it was Doctor Who in a specific episode from the 70s.

And

I think they were a little bit disappointed.

I think they wanted me to wait a little bit higher.

But it actually, yeah, it's been a huge influence on me.

But I was thinking, you're talking about the science of Doctor Who.

I think there's at least two or three different explanations for the death of the dinosaurs in Doctor Who.

And it's a little bit like science, because each time they come up with a new explanation, it gets a little bit closer to scientific truth.

I think the last time they did it was the Cybermen had crashed their spaceship into the Earth and like the big asteroid.

Well, I mean, that's true in the 1970s, but in the early 1970s, dinosaur episodes, I don't think people knew why the dinosaurs died out.

There was a lot of conjecture.

So, you mentioned, though, that there was one particular episode that influenced you.

So, which was it?

It was a thing called Frontier in Space,

which is a John Pertwee adventure.

And the reason why I remember it is because they had a Blue Peter special about the effects, how they did the models.

And I remember, I think it was probably Matt Irvine or someone like that

showing this model spacecraft coming into land, and then they had a little puff of air to kick the dust up around it.

I thought, that's so cool, that's what I want to do.

Interstellar is a film that's famous for paying attention to the scientific detail and taking artistic license where necessary.

But I was thinking about the black hole in particular.

Wasn't that published, your simulation?

Yeah, we well, we what we did to create the black hole for the film,

we had to write a new piece of software which implemented Einstein's equations from general relativity.

Kip Thorne, who's our scientific advisor on the film, who's a professor of theoretical physics at Caltech in Pasadena, he worked very, very closely with all the software designers in the visual effects department to create this new renderer, as it's called, which draws the images of the black hole.

And it calculates the way that the light beams travel through the gravitationally warped space and go into orbit around the black hole, get distorted, and then come back out and hit the camera to produce that image of the black hole with this big sort of halo around it.

It looks like a sort of hellish version of the London Underground logo.

And the software that we put together for that calculated it so accurately we discovered, well, we observed a few interesting things happening in the space very close to the edge of the black hole shadow.

We got a scientific paper out of that.

So

I am a co-author on that paper, which I do feel a tiny little bit of a fraud because I have a degree in sculpture.

What did you contribute?

Chicken wire and papier mache?

I saw a payoff.

I was going to say that that command of physics is impressive impressive from a sculptor.

Can you speak on sculpture with such

authority?

Well, the black hole and the wormholes you've mentioned before are

allowable in general relativity.

They are.

And the wormholes.

Speak wormholes.

Come on.

You're absolutely right.

There are two different sorts of wormholes.

Oh, what?

I've never heard those words read before.

Go on, no, there's two sorts of worms.

The wormhole in

interstellar is a spatial wormhole.

That's a shortcut in space so that you can travel from one place in space to another place in space almost instantaneously because you go down this little shortcut.

So those are spatial wormholes.

My PhD thesis was about space-time wormholes, and you're completely right to make the distinction because they are very different.

Three types of worms.

Worms.

Worms.

The space-time wormholes are interesting.

They are

not these shortcuts in space, but they are space-times where two disconnected portions of the universe can merge and become one.

And the space-time looks something like a pair of trousers.

So if you imagine a pair of trousers, then the two disconnected portions of the universe that are going to merge are the legs.

And then they come together, of course, and then the waist region that's the new universe that has formed out of the two disconnected pieces.

And the two disconnected pieces come together at what is called scientifically the crotch singularity.

Don't tempt me, madam.

And

the the interesting thing is that the consensus, the scientific consensus on the crotch is that it produces an infinite burst of energy.

And

this probably makes this space-time unphysical.

But again, we will have to wait until we have a full theory of quantum gravity to be able to

give the final word on this.

Well, welcome to Call My Bluff.

So, Ross

is space-time trouser singularity.

Sorry, I was going to say if this hasn't been condemned by the church already, it soon will be.

Well, we'll move on from Crotch Singularity to, it's really weird because I wasn't expecting you would be the one that would create all of the complaints.

I was going to,

we were talking about the questions earlier.

There's one here that says, Ross, has there been a lack of imagination in science fiction?

But it sounds a redundant question, though.

It's given me an idea for a new film.

So, Simon, I want to say, we've been talking a little bit, but in fact, black holes, we should get back to black holes, which is

they are meant to be, isn't that the TARDIS operates basically from a black hole?

That the very power of the Time Lords comes from a black hole?

Well, yes, but as the most recently, it's been established that the engine of the TARDIS is a black hole, frozen in the moment of its collapse and used as a power source.

But that's a fairly recent idea in Doctor Who.

You can see just how black holes have appeared in Doctor Who over the years.

A kind of

development of people getting used to the idea.

The first black hole is mentioned in The Three Doctors in December 1972,

which is about a year after Cygnus X1 was first being written about the first black hole that they think was discovered.

So they seem to have taken this idea out of the news and run a story on it.

And the Time Lords refer to it as the black hole, as if it's the only one, or it's the one that's near them.

And

the writers, one of whom would later go on to write the Wallace and Grommet films,

that they come up with a story where there's a beam of antimatter that leads into a universe of antimatter on the other side of this black hole, and that seems to be confusing to scientific ideas that were going around at the time.

When black holes are then used again in Doctor Who in a Tom Baker story, The Deadly Assassin, there's a thing called the Eye of Harmony, which the Doctor realizes as if this is something that Time Lords don't generally know is a black hole.

He kind of translates this

text from the old times which talks about it and goes, They're talking about a black hole.

And that seems to be the power source of the Time Lords.

A few years later, there's a story called The Horns of Naimon, where

Graeme Crowden's Saldeed has got two black holes, artificial black holes, that have created a tunnel between them, so he can get from one place to another and surprise everybody.

And again,

you're one of the stranger villains.

I'm all kind of show, busy Rogers and Hammerstein.

That is exactly what that story is like.

That was the last of the Douglas Adams stories, I believe.

Yes, the last of the transmitted ones.

And then,

but the doctor is traveling at the time with his companion, who's a Time Lord, Romana,

and she is completely surprised by this and doesn't think artificial black holes are possible and doubts the whole thing.

So, there's this kind of idea that even the Timelords don't think that black holes are possible.

Yet, more recently, when you get the Paul McGann TV movie, we learn that there's a the Eye of Harmony is inside his TARDIS.

And now we've got this thing where Matt Smith goes into the engines of the TARDIS and there's a black hole.

So it's never been really said: has that one black hole that was on Gallifray now been moved into the Doctor's TARDIS, or do all TARDIS's have a black hole inside them, or is it the Doctor's TARDIS special?

I actually think that's kind of missing the point.

What you're seeing is that the people making Doctor Who and the general public more

readily have got more used to the idea of black holes, and it's become tamer to use it in stories.

Do you think, Paul, that the

so a film or indeed a television series that pays attention to the science is necessarily better as a piece of art, a piece of film?

film?

Well, you know, I was thinking a bit about Star Trek the other day and the opening

voiceover where Captain Kirk is saying to explore the universe and seek out strange new worlds and new life and everything.

But now we've learnt that most of the universe is invisible, that it's dark matter and dark energy.

And so if you said to seek out and explore the 5% of the universe that we can actually see, it wouldn't be quite so interesting.

So I think the program makers, the script writers often take a lot of license with it.

But I often think the best science fiction is like an Einstein thought experiment.

I mean, interstellar allows us to go and explore and visit places that we couldn't do otherwise.

You know, and I thought some people complain: they say, oh, you know, if the spacecraft would get destroyed, they'd be killed by X-rays or gamma rays or whatever.

But then we wouldn't be able to go inside a black hole and see what happens to Matthew McConnelly.

So it's

kind of what science fiction does.

Kip Thorne got very defensive, didn't he, about some of those sort of charges.

He claims that he calculated virtually everything.

Yeah, he did.

He really did.

uh, he, I

was basically appointed the bridge to Kip whilst we were shooting the film.

So we were on the stage and we were doing things, and Chris would come and say, Chris Nolan, our director, would say, Oh, I want to do this with the spacecraft.

I want to blow it up.

And he wanted to break it, you know, it was a big ring-shaped spacecraft, he wanted to break it.

And it's still supposed to be spinning.

And I said, Well, I don't think it will hold together and fly to bits.

Let's leave a little bit in.

But he was adamant, he wanted to break it.

So I would immediately get on the phone and call Kip in Pasadena and say, He wants to do this.

Is this possible?

And Kip would say, Oh, it sounds very, very dubious to me.

I'll make some calls.

And he'd call up his friends at NASA, at JPL, and run this hypothetical question past them.

And then he'd come back and say to me, much to my surprise, if we assume the spacecraft has one-inch thick aluminium walls, it'll hold together.

So, we ended up breaking the ring on the spacecraft.

But

Kip

was involved throughout the whole process.

And

Chris, who, to be perfectly honest, you know, had I didn't think was that interested in science.

I've worked on five films with Chris.

He totally embraced that.

But he would do things like he would say to Kip, for instance, there's a planet where the time dilation factor is one hour on the planet's surface is seven years back on Earth.

And Kip said, well, I don't think that's possible.

There's no orbit that would be stable, that the planet could be orbiting the black hole that close for that

time dilation factor.

And he'd say, well, it's non-negotiable.

Go away and think about it.

And so, Kip went away.

This is how Chris works: he said, I want it like this.

All the great directors do this,

they don't listen to anybody else, they just do their thing.

And Kip went away and ran all of Einstein's equations and came back and again said, Well, much to my surprise, if we imagine a black hole that's a hundred million times the mass of the Sun spinning at very close to the speed of light,

then there will be a stable orbit where you can have one hour equals seven years.

It might not be a very nice place to visit.

That's fantastic, just the idea of Hollywood.

I don't care.

Change the law of physics.

Well, I don't care.

They've been running it for billions of years.

They need it for scene seven.

That'd be a simple request most of the time.

Was there a scientific advisor on inception?

I think Chris consulted with various

psychologists and people who dealt with the field of psychology and the imagery of dreams and things like that.

And he knows a lot about that himself.

But no, and there wasn't one working with us on a day-to-day basis.

And I think during Dark Knight Rises, I think I was possibly the nuclear physics consultant on that.

At no point did he go, well, basically, I want Bane to have this thing where no one's going to be able to hear him.

Ah, that'll be fine.

Could we put a switch on it that just goes, oh, that's better.

You may laugh, but monkey cage regulars will know that one of our guests, the cosmologist Sean Carroll, was science advisor on Thor.

Yeah, because he said that

I asked him, and I said, science advisor on Thor, why?

He said, obviously, you know that bit where they look at you go,

don't you know anything?

Because obviously they wanted the wormholes, space wormholes.

But what he said was merely wormholes.

So I'm now realizing how inexact he was, Ross, thanks to you.

Because we wanted the wormholes that the gods of Asgard travelled through to be as authentic as possible.

It's a clash of ideologies there.

I've just realised, actually, coincidentally,

the t-shirt I've got on is from the film Sunshine, on which I was science advisor,

in which the sun stopped working and we went to fix it.

But it was, it obviously worked because Benedict Wong is now working at NASA.

If you've seen The Martian.

That's a very specific reference there, but that's geeky.

Now, out geek that

in 52 years, it's been on air, it's only ever had one official scientific advisor, which was back in the early 60s.

And the production team, a new production team, came in in late 1966 and they wanted to make the show kind of connect with the audience more.

So they set more stories in the present day

and they made to base stories on real science.

And so the script editor at the time interviewed four or had lunch with four scientists who might be scientific advisors.

He met with

Patrick Moore, he met with the engineer Eric Lathwaite from Imperial, he met with Alex Comfort, who would later write The Joy of Sex, but at the time was a leading proponent of

science of senescence and aging, though I'd quite like to see what the Joy of Sex Doctor Who stories would have been like.

And finally, he met with Kit Pedler, who was an ophthalmologist ophthalmologist, an eye doctor,

and they got talking about lots of different things.

One of which was, how can we use the post office tower, the BT tower as it now is, which had just been built in a Doctor Who story.

And Kit Pedler gave him a story about, well, what about there's this mad idea of getting a computer to talk to another computer down a phone line.

So there's a story from 1966 called The War Machines, in which the internet creates machines that knock over boxes in London.

They talked about the various scientific ideas about how populations were controlled with music and drugs and you know this kind of idea that you could do that.

There were lots of theories that that was being done in some of the communist countries.

So you get a a story called The Macroterror, where the doctor and his friends free everyone from giant invisible crabs that nobody believes in.

And then there's a a story where they they were talking about this idea of what would happen if you had a a a planet that was just like Earth sharing its orbit, which it had been around since before

Pluto had been discovered.

It was one of the ideas about what could affect things gravity and explain some of the anomalies in Newton's ideas of how the planets went around the Sun.

And they were talking about this, and Kit Padler says, Well, there's this new idea, which is about rather than for space travel, rather than fitting spaceships so that they create an Earth-like environment in which astronauts can live, that's a very costly way to do it.

Maybe the way to have people working permanently in space is to kind of equip them with their own inbuilt air conditioning systems in a thing called cybernetics.

And that's where the cybermen came from.

And the cybermen were invented by the scientific advisor on Doctor Who.

And then they went off and made their own programmes.

And Doctor Who's never had a scientific advisor in that.

So the eye doctor, because

what happens?

Sorry, to I just with the weeping angels, what happens to blind people?

No,

if you look at them, they freeze if they can't move.

That's a good thing, isn't it?

Yeah, that's what I mean.

Like, if you look at them, they've frozen, and as soon as you blink, they're not.

And then a blind person would just literally straight in dead.

Or if the dog is looking at the angels,

not that I've spent a lot of time not sleeping because of this, right?

So, blind fellows there, he's got his guy dog, right?

He's approaching that, so he can't sit, so he's knackered, right?

But the dog's looking at the angels, so it's not coming closer, right?

So, what I don't understand is why doesn't the doctor just carry a dog?

See what I'm saying?

I'm glad I'm here.

Several dogs in case one blinks.

Exactly.

Two dogs.

Timing it so that every time that dog blinks, four dogs.

So you're going to really annoy now.

Get the statistics.

You say I should be.

Why did they bring back canine?

It was that bloody idiot Ross Noble.

So exactly.

K-9, that's what he's there for.

He is one of the weeping angels.

Faye,

I wanted to get to the w we talk about interstellar, we talked about wormholes, and and you mentioned that space wormholes, space-time wormholes, is all of them.

And and you you mentioned that that they're potentially possible, or at least not ruled out given what we know, which would mean that that time travel would be possible.

Uh the what's interesting about interstellar is that as I understand it, one of the interpretations for that film is that time travel's possible, but you're still in a consistent universe, so we don't have free will in Interstellar.

You see that Matthew McConnell's character can't stop himself

leaving his daughter's bedroom, he can't change history.

So, I'm going to ask a really simple question: Do you think we have free will?

Could you imagine a sensible universe, a universe, this universe, with wormholes and time machines?

I probably exaggerated the likelihood that

these things are possible.

I mean,

yeah, the consensus is that if, unless there are some surprises in store in the physics that we don't yet know,

it's most likely that they're not possible.

And

it's true that

when the story, the full story, the full space-time story

is consistent, as it is in Interstellar and as it is in Terminator and as it is in Bill and Ted's Excellent Adventure,

then you can't have free will.

Whatever happens has to happen, and

you can't change that.

You can't make a new decision.

You can't decide not to go in the time machine and go back in time.

But it doesn't allow for any

deviation, any it's very, very

finely tuned.

The universe has got to be very, very finely tuned.

And that is counter to the second law of thermodynamics.

It's although it's possible, and you can set things up so that they're just perfectly right, so that it's consistent all consistent.

Any little deviation will ruin everything.

So that's a feature of these

consistent

universes where there is time travel that most physicists would say is unnatural.

It's something that is not

accord with the physics that we understand.

It doesn't accord with the second law of thermodynamics, for example.

I suppose, though, Victor,

in

uh your world

there is uh that there there is a I suppose God sits outside time well no in your I'm not saying that as an insider possibly if there is a God then it's in my world as well but um but good s so in Christian theology let me put it that way in Christian theology God sits outside of time I think this is something which this is Anglican hesitation here

I'm trying to think what the answer might be

I'd like to say a bit more about free will if I may which is one of the great big arguments in theology in the last 2,000 years has been about free will.

And people come down on, you know, we've got it or we haven't got it.

And I, again,

laughing at myself, but of course that disguises a deep seriousness, think that we do have free will, but not much.

That, by the way, is a true Anglican answer.

I think we probably do, but maybe only a little bit.

We can't be sure.

Mince pie?

Fay, though, that the if you take Einstein's theories of relativity, if you take space-time, especially in general relativity, at face value, then you end up with this picture, don't you, of so-called block universe, which means that the whole thing is there.

So there's no definition between the unique definition between past, present, and future.

The whole thing's laid out, so the past is there, the future is there.

And in such a universe, we don't have free will, do we?

If you take the theory at face value.

If you think of free will as being something non-material and spiritual, then there's no place for that in physics at all, no matter what your picture is.

So we make decis the question is, how do we understand how we make a decision?

Well,

if you make a decision for some reason, then

that's the explanation of why you make the decision.

And I completely fail to understand what's problematic about that.

I mean, you you have a decision you to make, you think about it, for some

you weigh what you're going to do, what's going to happen if you make the decision one way or the other way, and then you think about it and you think, Well, I prefer this, and then you do that.

And a decision is made because of everything that's happened to you up to that point,

and

that determines which way you'll decide, or it's just totally random, in which case there's nothing to understand about it.

So, uh yeah, I I'm completely uninterested in the question of whether there's free will.

It seems to me.

See, that's a very typical physicist's answer.

You're all doing absolutely exactly as we'd hoped to cast you.

Well done.

Ross, what's your favourite monster?

Oh, monster.

I thought you said monster.

I was going to say ermine.

My favourite, what, Doctor Who monster?

Well, as I said earlier, I like the, I forget what he's called, but that Bertie Bassett robot thing.

The Candyman.

Candyman, of course it was, yeah, yeah.

Which, you know, as you can tell, I was very much in the Sylvester McCoy era when nobody was watching.

And they just went.

That's when, of course, when the Daleks first flew, of course.

Technically, they flew.

Oh, sorry.

But yeah, I'm not going to be able to do it.

Technically, what?

At last, you as the Doctor Writer have been able to go, well, technically, come on, Lee, that's the one.

Sorry, No, go on.

Technically, what?

So, so in Revelation of the Daleks, the Colin Baker Dalek story, the Daleks do, Davros floats above William Gaunt as he's electrocuting him.

So, Remembrance of the Daleks is the second one where we see a Dalek flying, if you count Davros as a Dalek.

It all gets a bit into, as scientists are prone to say, I think you'll find it's a bit more complicated than that.

Well, we have now, unfortunately, run out of time.

So, we asked our audience a question as well, and we asked them, Who would you like like to see play Doctor Who and why?

And what was lovely by the way was a lot of you just gave very very serious answers and went Ben Wisha.

He'd be very good.

That was excellent.

Is this a trick question?

Professor Brian Cox of course.

Or James McAvoy.

Chair, so she can turn back time.

Jeremy Clarkson, for his exceptional skills in hand-to-hand combat make him the most dangerous doctor in the world.

Me, Matt Smith.

J.O., Jeremy Corbyn.

It will be his only chance to save humanity.

Brian Cox, because look how shiny he is.

I always think you'd view more like an auton.

I think you are a little kind of auton, baby.

That's Jimmy Carr.

Nobody, because then I were again one hour of my boyfriend's time a week.

Felicity Bainbridge.

So, thank you very much to our guests: Faye Dowker, Simon Gurrier, Paul Franklin, the very Reverend Victor Stock, and Ross Noble.

We are back in January with our new series.

Victor, as it is Christmas, and you are our resident former Dean of Guildford Cathedral.

I'd like to make we don't see any of the others.

You are the only former Dean of Guildford Cathedral we ever have on this show, and I'd like to make that clear.

So, have you got a Christmas message for the Doctor Who fans and the Monkey cage listeners?

Well, I think what I want to say is this: that the monkey cage makes extremely complicated scientific ideas attractive.

That's why it works.

And for religious people, when the whole business of the universe, the way we behave,

the dreadful things we do to each other, is inexplicable, Christmas is about God

making himself attractive, and that's why we all have these Christmas lunches and too much to drink, and that's great, and sit about wishing the relatives would go home.

But the serious business is that we all feel a bit better on Christmas Day because this particular bit of Christianity is very attractive, and in that way, I think there's a kind of bow to the monkey cage.

And

I want to say, as a priest who knows absolutely, obviously,

diddly squid about science,

I want to say that

you make something really important

attractive to all sorts of people.

And thank you.

Thank you.

Picture stop.

Thank you very much, Pikta.

And so that brings us to the end of the show.

And I...

Ross!

Behind you!

A space-time wormhole!

I think this is a space-time anomaly!

No, no, it isn't.

Is it not?

No.

Oh, we've really overeated that one then, haven't we?

Never mind.

Tell you what, let's hope we get to the middle eight, though.

They like that.

That was the Infinite Monkey Cage podcast.

Hope you enjoyed it.

Did you spot the 15 minutes that was cut out for radio?

Hmm.

Anyway, there's a competition in itself.

What do you think?

It should be more than 15 minutes.

Shut up.

It's your fault.

You downloaded it.

Anyway, there's other scientific programmes also that you can listen to.

Yeah, there's that one with Jimmy Alkaseltzer.

Life Scientific.

There's Abby Brother Fiddy's dad discovered the atomic nucleus.

That's Inside Science.

All in the Mind with Claudia Hammond.

Richard Hammond's sister.

Richard Hammond's sister.

Thank you very much, Brian.

And also Frontiers, a selection of science documentaries on many, many different subjects.

These are some of the science programmes that you can listen to.

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.

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