Brian and Robin's Infinite Inbox

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Hello, and welcome to Brian and Robin's Infinite Inbox.

Yep, we have an enormous number of emails and letters that we've received during the last series of our Radio 4 show, The Infinite Monkey Cage.

And I, Robin Ince, and you, Brian Cox, will be dealing with some of these things.

And hopefully, by the end, as well, we are going to be dealing with the exact point of death of a strawberry.

So you've made the mistake again there by saying that we're going to be dealing with the exact point of death of a strawberry you've assumed the strawberry does die.

Well what I'm saying is we have been sent a theory, a rigorous theory, which I think may well illuminate this point of strawberry death.

The debate may well remain open, and there is much more research within a punnet to be done.

Because the question was, is a strawberry dead?

Well, the answer must be yes at some point if you're going to deal with the point of death of a strawberry.

Well, I mean, it may well turn out that you may well say, well, is that really the point of death?

It's clear that you can kill a strawberry.

You could put it next to a supernova explosion.

So I suppose it's valid.

Yeah.

Well, let's find out when we get to the end.

Yeah.

Certainly something worth

waiting for.

We've got a huge amount of kind of mail that predominantly gets emailed to us, and we get some delightful letters, and we get some very sometimes quite aggressive letters.

I would like to apologise, in fact, for the fact that unfortunately, we're not going to be dealing with some of the extremely abusive emails we get because they didn't tick the box that allows us to use them.

So they've remained very enigmatic in their abuse, which is pity because some of it was quite florid.

I thought

it wasn't rational.

It didn't make much sense, but it was florid.

Yeah.

The thing that interests me about

many of the suggestions or complaints that we get is that there's an assumption that the infinite monkey cage as a programme should in some sense be balanced, whatever balanced means.

But it's not balanced, is it?

It really is our

worldview on the radio.

I mean, I think, I would agree.

I do not think we are without bias.

I do not think that we are a balanced show, but I do think we're probably correct.

Absolutely.

I mean, I mean, we unashamedly prioritize reason.

And so that's not a balanced view because, you know, we get many complaints from irrational listeners saying, why is your program not more irrational?

You shouldn't really complain.

If you want an irrational programme, there are many others across all platforms on the BBC.

Yeah, we've, in fact, the radio falls absolutely packed.

It's packed with irrational shows.

Thought for the day.

I mean, we say rational, of course, we're only as rational as we can attempt to be.

But I would say that I'm, you know, artistically irrational.

I would say you are proper science, kind of just straight down there.

But if it cannot be measured, it does not exist.

You know, that kind of thing.

You're really straight down the line.

I don't say, I now disagree with you.

I don't claim that if it can't be measured, it doesn't exist.

I mean, it could exist, and we've not yet measured it.

Yeah, we said it under the series.

Evidence of absence is not absence of evidence.

Absence of evidence is not evidence of absence.

The way you said that had a lot more of a Bruce Forsyth air to it.

You can tell that you work in showbiz now.

Absence of events.

Absence of evidence is evidence of absence.

Come on, everyone.

Oh, Francis Bacon over there.

Even they were contemporaries.

Well, Francis Bacon and Bruce World cited.

Now, our very first letter is a lovely one from one of Radio 4's younger listeners, only 49 years old.

And they're not really 49 years old.

Do you see what I've done?

They're actually 10 years old.

And it harks back to the very beginnings of our show.

Dear Brian and Robin, I believe that the infinite monkey cage name is a subliminal reference to the notion that if you sat an infinite number of monkeys at typewriters for an infinite time, one of them would eventually type out the script to Hamlet.

The cage then represents the space occupied by the monkeys to carry out this task.

Cameron Butt, age 10.

A very good theory.

So I like the fact that the bar has been set very high now.

So a very eloquent piece of writing there from one of our 10-year-old listeners.

Yeah, I think the first complaint we ever got was, Well done, Radio 4, Yet Again You Celebrate Vivisection.

This is way back in 2009, 2009.

And as you know, it was just a loose collection of words with some idea of an infinite cage of monkeys.

Do we mean the universe?

What do we actually mean?

Well, arguably, the universe is an infinite cage.

Yeah, yeah, an infinite monkey cage is roomy.

So, let's get to the first question.

Now, this is a general question from

one of the shows where we did talk about black holes, but that has cropped up a few times.

And this is from Katrina Hillhouse.

Hi, folks.

I love the show.

I love the way people always talk with it.

It makes me feel a little bit more like Steve Wright.

Hi, Brian and Robin.

Loving the show.

This might make me sound like an idiot, but I have, which is normally my job on the show.

Yes.

Which is

my job.

She's auditioning.

She's auditioning for the job of idiot.

Remember, you do have to, Katrina, like me, be a genuine idiot and not merely playing the part of an idiot.

I have a question about black holes.

Is a black hole a three-dimensional object?

I've always wondered, because in artist renderings, it really looks like a flat hole, like a drain, only pulling things from one side.

Wouldn't a black hole pull everything from all directions?

If that's true, then wouldn't artist rendering be more like a visual representation of a cross-section of what a black hole would look like?

Just curious, I'm no scientist, so please be nice.

Yes.

With high precision, yes, absolutely right.

A black hole is a...

what you talk about when you say what's the I suppose what's the edge of a black hole or what defines where the black hole is is something called the event horizon which is spherical it's a sphere so it's just like a star so she's absolutely right and everything would would if things were flying towards a black hole they'd fall in from all directions so you do tend to see them drawn as this kind of a like a plug hole in a way with everything vanishing into it.

And that's that's she's right, it's a three-dimensional thing.

So, the next question, dear infinite monkeys.

Apparently, the world's first robot suicide has been reported from Austria.

A robot, the iRobot Rumba 760, tasked with cleaning the family home, was so fed up it was found burnt to death on a hot plate in an apparent act of suicide.

Is this the brave new world you materialist rationalists are leading us into?

And this is from Paul G.

Well, I'm going to let that pass without comment.

I mean, a more likely explanation.

This is science, in general, you need to search for the most likely explanation.

So,

either, right, either this domestic robot, which is basically a very simple and primitive computer that cleans your house, didn't notice that the hot plate was on, probably because it doesn't have heat sensors, and so it strayed onto the hot plate and set on fire.

That's one explanation.

The other explanation is that this thing, which has probably got the processing power of a mobile phone, became conscious, looked for a hot plate, jumped on it, and committed suicide.

I leave the listeners to decide which is the most likely explanation.

Personally, I think that it may have accidentally wandered onto the hot plate and caught fire.

Right, Brian, you'll be glad to know this is now back to physics, and this is a question from Pete, who signs it puzzled and intrigued.

He writes, Hi guys, when a photon is absorbed by an atom, an electron jumps up to a higher energy level.

My question is, how close does the photon energy have to be to the difference in energy levels for the photon to be absorbed?

Go on then, Brian, that old chestnut.

That's a super.

Does Melvin Bragg get these kind of questions, do you think?

These are good questions.

Very close.

You can see very close by the fact that if you look at the light from the sun, which and you split it up through a prism, it'll be a rainbow.

But it'll have black lines in it, which are very, very thin, specific so-called absorption lines.

So for example, there are two of those in the yellow part of the spectrum which correspond to sodium in the Sun's atmosphere.

So, they're telling you about

the electronic structure of, if you like, of sodium atoms.

And so, those lines are very thin, indeed.

And so, they're very specific frequencies.

So, the photon has to be extremely precisely matched to the energy difference between the orbits in order to make the electron jump.

And you can see that by looking at absorption lines.

Well, there, Pete Galton, I hope that you are less puzzled but remain intrigued.

Jeff Tucker, I have heard that quantum entanglement will be instantaneous across the universe.

I find it difficult to comprehend instantaneous in a relativistic universe.

Can you explain?

It's a brilliant question.

It's a very good question.

That myself and three other physicists at Manchuria have just published a paper on this, actually.

The question is: so, quantum theory is what physicists call non-local, as far as we can tell, which does mean that things appear to happen instantly.

But that violates

the spirit and the principles of relativity.

But our quantum theory, the one that we use at places like CERN, so the

quantum field theories, as they're called, are relativistic.

They're a union of quantum mechanics and special relativity.

So how do you square those things?

It's an extremely good question.

And the key thing to say is that information can't be passed faster than the speed of light in quantum theories, even in quantum theories.

So even though you seem to get effects that are absolutely instant and can span huge distances,

you know, as far as the theory is concerned, light years.

So, instantly.

It's certainly the case that you can't use that to transfer information or build a time machine.

But the way that that actually pans out is extremely complicated.

And so, I just point people to the paper that I just published with three other physicists.

You can access it online, and it's very long and got lots of maths in it.

Yeah, certainly not for for a 28 minute show on Forex Trail.

While we're recording this we have just had an email from Sweden come in and this is from I think it's Sega it might be Saga and she is currently studying second year high school college physics and she just said she's never heard of the idea of a particle dying until now and she's just been learning about the muon.

And she wondered if you could tell her a little bit more about this to help, obviously, with her revision and exams.

Well, the muon is a particle that's identical in every way to an electron, except it's more massive.

And so in particle physics, we've discovered 12 particles of matter arranged into three families.

So the muon is a heavy version of the electron.

The general rule in physics is that,

in particle physics, is that if a particle can decay, so die as the questioner puts it,

and it can decay into lighter particles than it will, if it's allowed to by the laws of physics and a muon is it is allowed to decay into an electron and

some neutrinos actually a neutrino so so so it will and it has a lifetime to do that

and so that that's what happens so so they fall to bits heavy particles fall to bits and the I mean the the classic example I suppose at the moment is is the Higgs particle we make them at the Large Hadron Collider but we don't see them they fall to bits immediately because they're very heavy 125 times as heavy as a proton.

So they fall to bits into lots of, there's lots of ways they can fall to bits.

And what we do in particle physics is we detect them.

So we detect all these ways they can fall to bits.

Now we had quite a few responses to our program on perception in which you and neuroscientist Bo Lotto had a row about the nature of consciousness.

You do get cross when we talk about the mind.

You know, Brian hankers for a world where everything could just be viewed objectively.

And I wondered how...

No, I live in a world where everything can be viewed viewed objectively.

You perceive

it objectively.

There is a physical reality out there, so we're not sort of brains in a jar on shelves making it all up.

But in another sense, we are literally making it up.

So that information comes in.

We have these measurements, and we can use physics to measure the world.

The deeper question is: what?

No, there can't be a deeper question.

The harder question,

because physics is actually quite easy.

So the harder question.

Wow, this has turned WWF pretty early, hasn't it?

So after hearing all that, Richard Holbrook wrote, Hi all, I enjoyed the episode on perception.

I always think of perception as the model of the real world we carry in our heads.

I agree that there is an objective reality out there, but scientists only work on models of reality.

They construct a model that the facts fit, but a new model that the facts fit and is predictive is equally as valid.

I always think of science as making models that fit reality closer and closer.

Just as a map can describe and predict terrain, the model can explain and predict the system we are modelling, but the map is not the territory.

Before that show, every now and again we argue when we're trying to think about what questions are going to be asked.

And you and I argued for about an hour, I think, over something that Bo Lotto said, which is that we as human beings cannot observe nature from the outside.

We can measure nature, but we ourselves are part of nature.

We have evolved as part of nature.

And we had quite an argument about that, didn't we?

Yeah, I mean, of course, we're part of nature, but there's a reality out there.

Nature is there to be observed.

And if we can only strip away the distortions that we introduce, I suppose, through our conscious experience, our preconceptions, etc., then we can see nature and describe it as it really is.

And

a lot of the practice of science, if you like,

is learning how to strip away those distortions to see that nature as it really is.

In the end, can we ever be entirely objective?

When you think of the limitations of the human mind and what we're beginning to understand about the human mind, it's an old debate.

It goes back actually to the foundations of modern science.

So you can look back into the 16th century and

the 17th century, and you'll see this debate being had.

Bacon, Bacon, the philosopher,

he said, there's a wonderful quote from Bacon.

He said, For the mind of man is far from the nature of a clear and equal glass.

Well, the implication is that what he understood to be the beginnings of science was that we need to make it a clear and equal glass.

So we need to work, we need to develop experiments and be very careful about the way we observe nature so we can remove the distortions.

He said our mind is like an enchanted glass, and we have to remove all this enchantment to make it clear so we can see nature as it really is.

And that really is part of the scientific method, the way that science progresses.

Part of it is doing experiments that strip away extraneous influences, the things you're not interested in.

So, if you want to know, for example,

how gravity works, then you don't want to be measuring air resistance.

Air resistance has got nothing to do with gravity.

So, if you drop a feather and a cannonball, and Galileo thought about these things and remarkably came to the right conclusion, if you actually do the experiment in air, then you'll find the feather floats to the ground, and obviously, the cannonball hits the ground first.

That's not gravity.

You're not seeing through a clear glass, you're seeing through the enchanted glass, and you've confused yourself and there's air resistance.

So what you really have to do is build a vacuum chamber and if you pump all the air out you'll find the feather and the cannonball fall at the same rate.

And so

I think that's the sense in which I kind of argued with you and with

you know Beau to an extent on the programme is because I think that there's two things here.

There's the study of the human mind and there's a study of perception, which is clearly a legitimate and useful thing to do.

But there's also that for a physicist, there's the study of nature.

And we're not at the point by a long way in physics that we can study the human mind as a structure in nature.

It's very difficult to do because it's so complex.

This is from James Watson, not James Watson, as in Crick and Watson.

How do you know?

I might be wrong on this, but I don't think James Watson's Facebook name is Sky Pimp.

But I may well be wrong.

It could be that, James Watson.

Anyway, so one of the James Watsons, who's been skydiving recently, he just wanted to say this about perception.

This was just a reaction he had.

He said, You were speaking about your friend the climber who fell 40 feet and was able to have, in his recall, time to try and select where he landed and to take action to avoid as much injury as possible.

I can completely understand this.

I'm a skydiver, and the average freefall time is 55 seconds.

One of the many amazing things within the sport is the stretching of your perception of time.

When you review the same freefall on a video playback, the time seems so much shorter.

Another thing that changes dramatically is the speed in which you think and act.

Wonderfully, Einstein's description of free fall is that it's the state in which there are no forces acting.

It's called an inertial frame of reference, according to Einstein.

So there are no forces acting on you at all.

So it'd be difficult to injure yourself during free fall.

It is always when the free fall stops that the problems occur.

Unless sometimes, you know, when you're doing free fall, but you've also decided to open a tin of peaches at the same time and you cut your finger on it.

I have stopped opening tins of fruit whenever I do a parachute jump now.

Yeah.

Now the next letter refers to the last program of the previous series of Monkey Cage.

That's when we were at the Science Museum and where we talked about science and wonder.

And we had cosmologist Neil deGrasse Tyson on, who told us about one of his darkest fears, which involved chimpanzees, strangely or not.

No, I had these sort of terrifying thoughts that our measure of our own intelligence is insufficient to actually deduce what's going on in the universe.

You know, can a chimp do trigonometry?

Well, no, I don't think.

And so why should we believe that we, who are just, you know, 1% different in DNA, somehow have magical powers to figure out what is necessary to truly understand our place in the universe?

So I lay awake at night,

not being able to sleep, worried that humans as a species are too stupid to understand our actual plight.

I thought you were going to finish that with, can chimps do trigonometry?

I've just listened to the last podcast from Dan.

I've just listened to your last podcast from the Science Museum.

The show ended with a guest asking the question, can chimps do trigonometry?

And everyone agreeing that the idea was ridiculous.

And I would like to say I did not agree with the idea being ridiculous.

I said very little about chimps and trigonometry, Dan, actually.

Maybe a couple of the others did.

And Dan, they can't do trigonometry.

Well, this is the thing, I suppose.

This is where Dan, who is

rather lovely, says, I'm an evolutionary biology misfit and lover of the cocks and a Sagittarius.

As if he's trying to woo you in and then push you away at the same time.

What's he trying to say?

He's trying to say that chimps can do trigonometry.

Well, what he's saying is, in terms of practically, even though they may not be aware of the trigonometry, I suppose, what he's saying is the angles and distances chimps, and of course other animals, calculate whilst going about their day-to-day business, swinging on trees, etc., is incredible.

Well, they don't calculate it.

They have an instinctive map of the way that the universe works, how objects behave in their environment.

That's what they do.

But they don't do trigonometry.

They don't calculate.

They don't know about sine and cosine and tangent.

Ask a different, ask a new question.

That's nonsense.

Right, okay.

Thanks, Dan.

That's Brian for a thing for you.

Anyway, so now our next letter is a rant about bias.

And obviously, by the mere fact that I've said it's a rant, it has shown that I have my own personal bias, that I've now biased your view of the letter.

And later on, Brian, if you're very lucky, we will deal with Timothy Leary's idea of reality tunnels.

Anyway, so I have warned you, and it's a complaint about our programme on geology and dinosaurs when Hermione Coburn was explaining to Python Eric Idle how life at Cambridge could have taken a different turn had he paid more attention in geology class.

Prior to plate tectonics, all geoscientists were really working away in their own niche areas.

Plate tectonics was the grand unifying theory that brought everything together.

So who was that?

Who did that?

Who was plate tectonics?

Well, a number of names, but they were all at Cambridge about the same time as you were.

I just made a career choice that was wrong, you know.

In a frenzy of her pro-British gush about your local fossils and Cambridge-centric science, your expert declined to mention Canadian Tuzo Wilson, who surely made the greatest contribution to plate tectonics theory.

How's that for a partisan rant?

Rob Chappell, British Columbia.

They're close to where you live.

Just look at where you live.

Just to just.

What's your place of residence called?

British Columbia.

Enough said.

We also, of course, we did a show on science and spin.

Sheena Cruikshank has a rant about factual inaccuracy in the media, but prior to this, he was espousing nonsense about asthma and allergy being far less common in parasite endemic areas.

Shakes head and slowly sighs.

Biologists, you didn't get into medical school.

Get over it.

Thanks, John.

We had a lot of feedback, and it was very nice from people saying how wonderful it was to hear James Burke back on the show.

Yes, it was, wasn't it?

And that was.

And surprisingly, I didn't know that he taught medieval English in an Italian university and then wandered back to London and they said, well, why don't you present Tomorrow's World?

Well, that was the great thing because we neither of us had realised that his background was.

He taught Middle English, didn't he?

He taught Middle English.

And then basically at that point, the BBC went, we kind of want some people who teach the arts to do some things about science.

And he thought, this will be fun.

I like the idea of doing Tomorrow's World.

And that was how the career came about.

Let me have a look.

Undoubtedly, the show that had the most reaction, I would say, in terms of Faraday reaction, both on stage and afterwards, was when we dealt with Hilbert's Hotel and Infinity.

Infinity is a word that belongs to the wordy people, like me and Robin.

You cannot place a numerical value on infinity, and therefore you cannot have a plus one to it or a minus one.

We've just proved that you could, so we can stop.

It's been proved.

That's not proof.

That's not the process.

That's a problem with you.

That's just

word proof.

It's gameplay.

There are either an infinite number of numbers or there aren't.

There are.

Hello, all.

I enjoy listening to your programme.

I've always been interested in maths.

I was amused to hear the multiple explanations of understanding infinity, but I'm sure you all missed the simplest and most obvious one.

It is that any number or formula is infinite if it is divided by zero.

Brian Cox said that minus two is less than zero.

This cannot be so, as any number or formula divided by minus two is not infinite or above infinity, but simply becomes negative.

I'm nearly seventy-seven years old, catching up on Doctor Who, but still remembering everything I've learned with revision.

So, what do you reckon to that then?

You've got to be extremely careful here.

That's not a threat, is it?

You said that in a way, doesn't it?

Ray, you've got to be extremely careful.

Number theory.

We're talking about a branch of mathematics called number theory.

And if you listen to the programme, you go back to Sabre, you'll find it's extremely complicated.

As we discussed in the program, there are many different kinds of infinity, many different sorts of infinity.

This is what Cantor did.

The huge volumes of mathematical work on what we mean by this infinity and that infinity and the other infinity, as we discussed in the programme, the infinities are bigger than other infinities.

It's all a complete mess.

And division by zero is an undefined thing.

It's a good question.

Number theory is fascinating.

And some others on this as well.

Why is it that no one thought to correct John Lloyd when he talked about longitudinal lines being parallel?

Surely as the originate and terminate at singularly fixed points, they can never be considered parallel.

Having said that, Brian is still wrong about infinity, spouting the same drivel that comes from the mouth of sportsmen about contributing 110%.

No matter how much harder they try or how many ones you add to infinity, it's still infinity.

Who wrote that?

That's from Liam, but to be fair, he says it's still infinity.

Or have I missed something?

You've missed something.

Okay.

What I find really interesting is we've got loads of letters, loads of letters about the mathematics programme.

And it is true that number theory, pure mathematics, is abstract and counterintuitive and fascinating.

And it's worth investigating.

So if any listeners are interested and found that programme confusing, it is extremely confusing and difficult, number theory.

A long, long history of some great mathematicians all working very hard to just show

they're looking at the logical structure of mathematics.

And it's very complicated and very counterintuitive.

Yeah, undoubtedly, I think in the last series it was the show that people, we got the most kind of engagement from people, enormous

number of, we definitely should.

And this is from Joseph Joseph, age 16.

Brian said that there were 88 narcissistic numbers in base 10.

Well, is that my opinion?

No,

he didn't say it was your opinion.

He said that you said.

So he's saying that that's fair enough.

Brian said that there were 88 narcissistic numbers in base 10.

And as I was on holiday in the French Alps and had no internet connection to check what they were, I created a spreadsheet to calculate them.

On the plane back, I began to crunch the numbers and identified the first 17 numbers if zero is counted.

Age 16.

But the caliber of our listeners is quite remote.

That's wonderful.

I have planned to continue calculating the narcissistic numbers until I've found all of them using the spreadsheet, but that may take a while.

Yes.

Thank you, Joseph.

Wonderful.

That is, well, that's part of as well.

We should say that what the show is about is that we're not attempting to give a half-hour answer.

Here we go.

This is this subject.

We've now delivered you that module.

What we hope we achieve by doing the show is to engage you enough that you think, I need to know more about this.

And so many of the letters that we've got, I mean, I am now in this studio surrounded by the letters that we didn't manage to get to of the few that we printed out.

And there are hundreds of them.

We want to make people think, don't we?

Because I know we both like thinking.

Thinking is a wonderful thing.

Being challenged is a wonderful thing.

And so if you listen to the monkey cage and hear something you don't like, you find it challenging, that should be a pleasurable experience.

Or one that is both agonising, but nevertheless still worthwhile.

Yes.

Thank you very much for listening to Brian and Robin's Infinite Inbox.

As you see, it wasn't infinite.

In fact, we had a really great letter dealing with the dead strawberry and the definition of death of a strawberry.

We've had no time to read that.

Well, no, we were going to give the answer.

Is a strawberry dead?

I was about to give the definitive answer, but unfortunately, we've run out of time.

We had the exact point.

of the strawberry demise, but that will

try and get some form of equation up on the website as soon as possible.

But thank you very much for listening.

Thank you very much for everyone who has sent their emails and allowed us to read them out.

And as we said before, do not fear fear questioning the world, questioning scientists, asking it's to be confused is actually a very, very exciting thing.

But to desire to remain confused, that's where the disaster arises.

You'll never get all the answers, but try and make sure you can get as many as possible in your finite existence.

The best definition of science I've ever heard, science is the desire to remain confused.

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