Original subtitles

Each one of us is made from mere matter...

..yet we are matter with curiosity,

we ask questions.

And, in the private world of our minds,

one particular question burns...

Why are we here?

A scientific answer to this question

may not be far away.

MAN CHANTS

If the existence of any one of us is singled out

the answer to the question "Why are we here?"

looks like pure chance.

Like any particular individual,

baby Shurik was born into this world as the culmination

of a chain of apparent coincidences.

A chain so long that, at first sight,

it looks highly improbable.

The chance that a particular sperm reached a particular egg...

The chance that baby Shurik's parents happened to meet...

and their parents too...

and generations of ancestors before that.

But don't stop there.

The apparent coincidences go back much further than that...

..to our planet and its position in space.

We appear to live on a perfect planet in a perfect universe.

It feels as if it's been made for us.

The Earth orbits at just the right distance around just the right star

for the temperatures on its surface to be just right

to permit liquid water to exist.

And those temperatures have remained just right for four billion years,

which is just the right amount of time for us to have evolved.

And this seeming luck continues beyond our solar system.

We live in a universe that's expanding at just the right rate

for stars and galaxies to form.

And within those stars, the forces of nature are just

the right strength to allow them to assemble the elements of life,

carbon, oxygen and iron, in their cores.

If you trace it right back,

the odds of YOU existing in this universe don't just look small,

they seem almost infinitesimally small.

Why are we here?

Is our existence merely accidental?

And if we are just happy accidents,

then what about the universe?

Is its form, its nature, its very existence

also accidental?

And if that's the case, what does it mean to you?

Well, I think modern science is very close to answering these questions

and, in this film, I want to tell you why I think that.

WIND HOWLS

Shankar is 12 years old

and has lived at this school since he was eight.

He sees his parents only every three months...

But, to him, it's worth it

because he has a singular life ahead of him

as a Hindu priest, or Brahman.

Shankar is one of 40 students here,

all of them training for the Hindu priesthood.

CHATTER AND LAUGHTER

Their day follows a strict routine starting at 5am.

BELL CHIMES

CHANTING

Almost every day the students chant between seven in the morning

and seven at night.

They're chanting Vedas, ancient verses which date back

4,000 years, containing the poetry and myths

on which Hinduism is based.

BELL CHIMES

These religious verses hold some unexpected thoughts.

They contain the concept of zero

and they touch on the notion of infinity.

And they use mathematical concepts such as Pi, square roots

and Pythagoras' theorem.

And, in one part of the Rig Veda learned by the older boys,

you can find a very interesting thought.

It addresses a crucial question

about the formation of the universe.

"The gods are later than creation."

I think that's a remarkable sentence.

It displays real intellectual rigour and honesty.

It's obviously not a sufficiently good answer to say,

"Well, all this exists because it was willed into existence

"merely by some kind of deity."

It's reasonable to then ask the question,

"Well, what's the origin of the deity?

"Has the deity existed forever, has the universe existed forever?"

So, I think, just seeing signs of that...

that kind of thinking which is really what you might say

the prerequisite or the first signs of a scientific way of thinking.

The scientific approach acknowledges that if we're ever going to ask

grand questions like "Why are we here?"

we have to begin with "how".

In my view science is a...a humble pursuit.

It starts by asking very simple questions, asks questions like,

"Why is it that when you let something go

"it falls to the ground?"

You let it go, it falls to the ground again,

falls to the ground again, you observe regularities in nature,

tiny, small regularities,

and try and explain them and model them, understand them.

Through that process we've been led to

an intellectual framework that maybe allows us

to answer questions about the very origin of reality itself.

From the marketplace to outer space,

those regularities in nature can be found almost everywhere you look.

Galileo said nature is a book

written in the language of mathematics.

And, the more you start to look for that language,

the more you see it...

..everywhere.

Rivers meander through the landscape in a seemingly random way

and if you just look at a few turns

then they will be random.

The river might change its course

because of some geology, a big rock formation.

But if you look at a river over a large length,

say tens or hundreds of kilometres,

then you see that the meanders aren't quite random,

a pattern emerges, there's order there.

This is the satellite picture of the bend in the river,

the meander you can see here,

and the mathematical relationship,

the pattern that we're looking for, is this.

If I measure the wavelength of the meander,

which is just the length between the point

where the river starts to turn

and meanders up and then meanders down and comes back again,

you see it's around 11 centimetres on this map.

And then if I measure the width of the river at this point

then it's something like one centimetre,

so the ratio of the wave length

of the meander to the width of the river, in this case, is about 11.

Now, the interesting thing is that if you take this whole river,

so not just one bend but hundreds of bends,

you'll find that that ratio is always somewhere

between about 10 and 14.

What's very interesting is it's not just this river,

this isn't a special river.

If you look at any river on the planet,

no matter how small or wide,

you'll find that it's always somewhere between 10 and 14.

There's obviously some pattern there,

it reflects something fundamental about the way that fluids

flow across the surface of Planet Earth.

And this rule can even be seen on other planets.

On Mars, the rivers have long since dried up,

but the arid river beds show the same meandering pattern.

And on Titan, the largest moon of the planet Saturn,

the rivers are made of methane cutting through a bedrock of ice.

But even here the same ratio appears to exist.

This rule seems to hold true for every river

found across the solar system.

Order is hidden in everything, from rivers, rocks and landscapes

to living things,

even the most exotic and elusive of creatures.

"In the days when everybody started fair, Best Beloved,

"the Leopard lived in a place called the High Veldt.

"The Giraffe and the Zebra and the Eland and the Koodoo

"and the Hartebeest lived there,

"but the Leopard, he was the 'sclusivest

"sandiest-yellowish-brownest of them all."

Rudyard Kipling's Just So story, How The Leopard Got Its Spots,

tells the story of an Ethiopian man who was the Leopard's friend,

he used to go hunting with the Leopard.

And one day he noticed that the Leopard wasn't being

very successful, it had a plain, sandy coat,

whereas all the other animals had camouflage.

He said, "That's a trick worth learning, Leopard."

So he took his fingers and his thumb and he pressed

into the Leopard's coat to give it that distinctive

five-pointed camouflage pattern.

So, in the absence of an Ethiopian hunter present at the birth

of every leopard, how did the leopard get its spots?

No-one disputes the reason why leopards have spots,

they evolved as camouflage.

What's less obvious is how the pattern appears on their coats.

(WHISPERS) Oh, there, yeah, yeah.

Let's have a look.

Fantastic.

He's ducked down into a little... little valley.

It's really interesting, the moment you lose sight of the leopard

then you turn round to see it again,

it's very, very difficult to find it.

You've essentially got to wait till it moves.

It just shows you the effectiveness of camouflage.

How does that complex camouflage emerge from the millions

of separate cells across the leopard's skin?

Measure out...

..a precise amount of indicator.

Then I'm just going to add it in.

It turns out that complex patterns can emerge

from simple ingredients.

And, mix them up.

Now, if I pour this into this Petri dish...

There, you see?

And now can you see the colour coming back,

fading back in?

It's not the usual chemical reaction,

you mix two things together, you get a big bang or a cloud of blue smoke,

which is what all chemists love.

This reaction is continually oscillating

backwards and forwards.

So we started with the simplest of ingredients,

mixed them together

and they reacted in such a way

that complexity,

that pattern, emerged from the underlying simplicity.

A similar process happens in living things.

When the leopard was still an embryo,

it's thought that two competing chemicals, washing over the skin,

created the distinctive spots.

So if you have a sandy background,

then you can imagine one of these chemicals

that causes or stimulates pigment to appear,

so as it grows you get a dark spot.

Where it's inhibited and drops you return to the sandy background.

It grows again, you get a dark spot

and returns to the sandy background.

The same principle is believed to create the stripes of the tiger,

the zebra and the sea snail, to name just a few.

Scientists get very excited

when they discover an explanation like this

because it means we've understood something much deeper about nature

and that's that complexity masks an underlying simplicity.

All the intricacy that we see across the natural world

emerges from a few simple laws.

The meander of a river and a leopard's spots

are just two examples of patterns in nature,

but there are countless more.

By looking carefully at the patterns in nature

and trying to understand their origin,

that's what Copernicus and Kepler

and Newton and Einstein and Galileo

and Curie and Dirac and Feynman and a thousand others have discovered.

There are regularities in nature,

there are patterns as far as the eye can see,

on every scale from atoms to galaxies

and those patterns are a reflection of the simplicity and beauty

of the underlying laws of nature.

A blueprint for creation does exist,

a scientific one.

But how do the laws of physics explain the existence

of human beings?

How, or why, did atoms come together to form us in particular?

The game of cricket is unfathomable to some

but to those who understand it it's bewitching.

I really love it, I just can't express it...

I...I don't express it in words.

My dream is to play for India.

This is what I've been aiming for since my childhood.

Today Subitu Bose and his team-mates

are playing against rivals Neerja Modi School.

Cricket is based on a set of rules

and they haven't altered significantly since the 1800s.

CHEERING

But, despite the existence of these rules,

no match is ever predictable.

Take, for instance, the ball.

Climate makes a big difference to its swing,

dew picked up from wet grass

or scuffing from dry ground...

..not to mention how it's bowled.

And then there's the bat.

Each batsman has a preference for a bat of a particular weight

and that will affect his stroke.

Not forgetting the temperament of each player,

the mood of the umpire

and the mood of the crowd.

When you get so many variables, the number of possibilities

becomes enormous and yet all this complexity

emerged from a set of fixed rules.

A game of cricket is played out according to a set of simple laws

and so it is for the universe,

and here are the laws of the universe.

This is the standard model of particle physics

and this is Einstein's General Theory of Relativity

and you can fit them easily on a scorecard.

And here are the laws of cricket

and it has to be said, at least in this notation,

that cricket is more complicated than the universe.

But even given these simple laws,

the number of ways that both games can play out

is effectively infinite.

So the laws do not make the outcome predictable.

But all we really care about is the outcome.

In the case of the game of cricket - who won?

In the case of the game of the universe - we exist.

And for the cricket match,

the result could have turned on the tiniest,

most insignificant little event,

the way the ball gripped the pitch and deflected off

a couple of blades of grass, clipped the edge of the bat

and was caught by the wicketkeeper.

And it's the same for the universe.

Some collision of two dust particles ten billion years ago

could have led to a chain of seemingly insignificant,

infinitesimally unlikely little events

that led to something that we care deeply about.

Our existence.

Today the way the game of cricket played out

had an undesired outcome for Bose.

The fielder caught my, er...

caught the ball here.

Had I have hit the ball a little to the...

to his left or right, it would have gone to the boundary.

But, sadly, it went straight to the fielder.

I was like, "Ahh...

"What have I done?"

Just like a game of cricket,

the way the universe played out to create us humans

was not determined by the rules alone.

Chance played a part, too.

This temple's over a thousand years old,

it's dedicated to Lord Shiva the Destroyer

and it's built in the Tantric tradition,

which is at least in part a celebration of pleasure.

But whilst I find some of these suggestions instructive,

that's not why we're here.

We're here because of the location of this temple.

Because this temple is in the centre of a crater, three kilometres wide.

Geologists are still debating what made it

but it could well be the scar left by a meteorite

smashing into the Earth.

Throughout its lifetime the Earth has been

constantly bombarded by objects from space.

Think about one particular collision,

the impact that probably wiped out the dinosaurs 66 million years ago,

and think about the history,

the lifetime of that rock that smashed into the Earth.

Imagine one particular day in the lifetime of that rock,

on one orbit, perhaps billions of years ago,

when another rock, no bigger than that,

instead of missing it, hit it,

smashed into it and changed its orbit very, very slightly.

And, over millions and millions of orbits, that change

would have got amplified, until, perhaps, that day,

66 million years ago, instead of smashing into the Earth,

the dinosaurs were looking up at the sky

and they saw a fireball blaze across the sky

and miss rather than hit.

That would have changed history.

In all probability the dinosaurs would still be roaming

the surface of the Earth today and we probably wouldn't exist.

But the rock DID strike, the dinosaurs WERE wiped out,

and purely by chance our human existence became possible.

And fateful accidents of equal importance for our existence

have also happened on a much smaller scale.

CAMEL GRUNTS

In Pushkar they have quite a tradition of camel racing.

BRIAN CHUCKLES

There's a saying, apparently,

which is the camel and its driver go their own way...

..and there's the proof.

Despite that, there's a surprising similarity between camels and us.

Now what I'm going to do is I'm going to take a sample of my cells

and a sample of the camel's cells.

What's his name? Rapi. Rapi.

Rapi? Yeah. Right.

So to take my cell sample is quite easy.

I just have to...

..rub that on the corner of my cheek

so there are my cheek cells on there.

I'm going to do the same now to Rapi, but could you hold him,

hold his mouth open?

CAMEL GRUNTS

Actually, you know what, can I ask you to come?

There's no way I'm going in there!

Can you just rub that on his cheek?

That...that's going to be enough, that's plenty.

That's plenty, yeah, and then hand it over there.

There we go!

Right, thank you, thank you.

I apologise.

So now we've got a... a sample of Rapi's cells

and a sample of my cells

and we'll make a comparison.

I apologise again.

So this is the slide of my cheek cell.

You see there it's stained blue.

Quite small, but I can see detail inside it.

And this is a slide of the camel's cheek cells.

And the most obvious thing to say is they look identical,

impossible to tell them apart,

and that's because for all intents and purposes they are identical

and that's because myself and the camels over there are mammals.

But...

if you look more closely,

then you see that the cells have

many structures inside them.

The most obvious feature is the nucleus,

where most of our DNA is stored.

But you can also see hundreds of little dots.

Many of these structures are called mitochondria.

These are the power stations found in the cells

of every complex living thing.

And, yet, once upon a time these essential structures

were separate, free-living creatures.

A long time ago, two or three billion years ago,

the Earth was populated only by single-celled organisms,

two great kingdoms of life, the bacteria and the archaea,

and, it has to be said, things were pretty dull,

there was nothing that we might call complex and, in fact,

very little happened.

Those two single-celled things just stayed the same

for billions of years.

But then one day, quite by accident, everything changed.

What many biologists believe to have happened is that a bacterium

got inside an archaean and for some reason wasn't digested.

Instead, a symbiotic relationship began.

The bacterium may have been protected by the archaean

while the archaean got access to the energy generated by the bacterium.

Once that cell had access to the vast amounts of energy,

the potential that the internal bacterium gave it,

then basically all hell broke loose.

And that energy allowed the cell to begin to work in larger colonies,

to begin to build complex living things.

So the mitochondria in your cells today are the descendants

of that chance collision billions of years ago.

That singular event, that fateful encounter,

was purely accidental, but the cells that it produced had such

a survival advantage, the energy made available to them

by the mitochondria, that its effect was amplified beyond imagination

by natural selection, which is not accidental and it is non-random.

So it's the interaction between accident and rules,

chance heavily constrained in the framework of natural laws,

that led to the evolution of humans here on the Earth.

In our universe there was no particular aim,

no intention for us humans to exist.

Instead the life of the universe is just like a game of cricket...

..where rules and chance play out together...

..and quite by accident happen to produce a human universe.

Over the course of centuries we've worked to find

the combination of rules and accidents that made today's world.

We now understand the laws of nature so well

that we have at least a reasonable scientific understanding

of every step in that chain, from the present day

to the first few moments after the Big Bang, and that is a tremendous achievement,

it's the great achievement of modern science.

But just as the origin of the gods themselves is

questioned in the ancient Hindu hymns and the Rigveda then

so we are faced with a question, a very profound question -

who wrote the rules of the game,

what is the origin of the laws of nature?

What is the origin of the universe itself?

What went before the Big Bang?

It's a question that takes us to another world entirely.

A samurai sword is both sharp and strong.

Able to cut a body in half...

..but precise enough to slice through a single hair.

Gassan Sadatoshi is a master sword maker.

His family have been making swords for over 800 years.

The first stage is to reduce the carbon content of the raw material.

If there's too little carbon it'll be soft,

but too much and it'll be brittle.

This is all a remarkably high-precision process,

everything that they're doing matters to make the perfect sword.

And even the force with which they hammer down matters,

that helps set the precise mixture of ingredients,

and they're aiming for precisely 0.7% carbon in that steel.

Repeated heating and layering mixes the iron and carbon

so the block is uniform.

This process can take weeks.

The final stage is to harden the cutting edge of the sword,

a process called quenching.

In the case of a Japanese sword, if you get all the ingredients right,

the precise mixture of iron and carbon,

if you get the temperature right, you get the hammering right,

everything right, over a year, then you get the perfect sword.

Now, in the case of the universe the ingredients aren't things

like iron and carbon, of course, the ingredients are a set of numbers,

they're called constants of nature, they're things like the strength

of gravity, the speed of light and the masses of the particles.

And they also require precision.

They have to be set in just the right way

if you want a universe that supports life.

In the same way that a samurai sword would be weakened

if the ingredients were different, the universe might be unable

to support life if the constants of nature were somehow altered.

Now, if I was some all-powerful deity, which arguably I'm not,

then I could imagine varying all those constants of nature

to see what happened.

I could imagine some great big control board with little knobs on it.

One of them changes the strength of gravity, the next one changes

the mass of the electron, the next one changes the speed of light.

And the question is how much freedom do I have

if I want living things to exist?

The answer is, not very much freedom at all.

If at the Big Bang the strength of gravity were increased

then the universe would have collapsed in on itself

before life had time to evolve.

But if the strength of gravity were decreased then galaxies

wouldn't form, so there'd be no planets, no stars and no life.

If you decrease the speed of light by just a few percent

our universe would have no carbon in it.

Increase it by about the same amount

and our universe would have no oxygen.

Because we have no idea why the constants are the values that they are

then we're presented with something of a mystery, because you can ask the question,

well, if it's just random, if indeed the universe began and somehow

these random numbers got chosen, then how lucky are we that we exist?

How lucky are we that we live in a universe where those constants

are just right to allow galaxies to from and stars to shine

and elements like carbon to form in the hearts of stars?

So what could account for the uncanny precision of this set of numbers?

Hello, can I have just one? Yeah.

Thank you.

You know, our universe, with all its beautiful laws of nature

and its finely tuned constants, feels incredibly lucky.

I mean, it's like buying a lottery ticket and winning the lottery,

but it's stranger than that, because it's like winning

the lottery in which only one ticket was ever printed.

But that's of course not how a lottery works.

Yes, it is extremely unlikely that I'll win the lottery

with this ticket, but there are millions of tickets printed

so it's not surprising at all that someone wins it.

So could we think of our universe in the same way as the lottery?

The reason that we appear to live in a perfect universe with

the perfect numbers, the perfect constants of nature,

the perfect laws, is because there are in fact countless millions,

perhaps an infinite number of universes, each with different

physical laws, different numbers, different constants of nature.

Then we shouldn't be so surprised to live in the perfect universe.

It's like the lottery - somebody's got to get the right ticket,

somebody's got to win it.

Just as the lottery has many tickets,

each bearing different numbers...

..so there may be many universes,

each with different values for the constants of nature.

Universes with stronger or weaker gravity,

slower light or faster light.

Now, that might make sense mathematically

but is it really a sensible suggestion,

an infinite number of universes?

What does that mean for reality?

Miyake Jima island.

3,000 people live here, making a living from the sea.

But it's a precarious place to call home.

Because this entire island is an active volcano.

Occasionally it belches forth scorching lava that

incinerates anything that stands in its way.

Until an eruption in 1983, this was the island's school.

But volcanism doesn't just destroy, it also creates.

Around 30,000 years ago this whole island emerged

from the vast emptiness of the North Pacific Ocean.

And it's not just this island, it's the whole of the Izu Archipelago

and much of Japan.

All of these islands have risen up

out of the ocean, seemingly from nothing.

And it's even happening right now.

This island, called Nishinoshima, has been growing steadily

since it suddenly appeared in November 2013.

If we didn't know better, we might ascribe that creation

to the act of the gods, but we do know better

because we know about geology, we've done some science,

so we know that the origin of this island is volcanism.

It comes from the inner heat of the Earth, which is itself a leftover

from the history of its formation 4½ billion years ago.

So we have a mechanism for the creation of new land.

Contrast that with the scientific explanation for the origin

of the most important thing of all, the origin of the universe itself,

and for decades we've been happy to say

the universe began at the Big Bang

and it's almost as if we're not to ask what happened before.

There was nothing before,

there's no scientific mechanism to explain how the Big Bang occurred.

But there are now plausible theories that provide

a mechanism for how universes might be made from apparently nothing.

So what is this magical theory that explains

the origin of the universe, and how did we find it?

Well, the answer is it's a theory called inflation,

and really the clues to the theory were there all along,

we just had to look for it.

They lie in the rules of the game.

If there's one basic rule it's this - things have to happen.

Nothing, emptiness, is about the only thing that's

forbidden by the rules of quantum mechanics.

Before our universe became filled with

particles of matter, it wasn't empty, it was filled with energy,

and like the surface of the sea it was constantly fluctuating, rippling

with a form of energy that causes space to expand exponentially fast.

At the trough of one of the waves, the energy driving

the expansion fell below a certain level.

So that region stopped inflating and the energy was transformed

into the recognisable particles of today's universe.

And that transformation is what we see as the Big Bang,

the birth of our observable universe.

The theory of inflation is extraordinary

and extraordinary claims require extraordinary evidence.

Well, here is the extraordinary evidence.

This is a photograph of the oldest light in the universe

and it's got many intricate and detailed properties.

The most obvious one is that it's an extremely uniform glow,

it's almost all at the same temperature.

This and all the other properties of this ancient light are best

explained by an inflationary expansion of the early universe.

No-one has thought of any theory that can reproduce this

other than inflation,

and that is why I love physics.

Isn't that remarkable?

But, just like the formation of islands or any other

mechanism in nature, inflation needn't stop at one universe.

Why should it?

The process of inflation could be going on eternally,

always making universes, even now.

And each one of these universes

could be like a ticket in a lottery...

..bearing different numbers for constants of nature...

..such as the strength of gravity or the speed of light.

So amongst them all...

there has to be a winning ticket.

A human universe.

It's absolutely inevitable.

If the theory of inflation is correct, it explains

how our universe appeared apparently from nothing.

And it also strongly suggests that there's not just our universe

but a vast number, perhaps even an infinity of them.

Now we've known for a long time that we're infinitesimal specks

in a vast universe, but now the suggestion is that

we're infinitesimal specks in a vast infinity of universes.

Our current best theory for the origin of the universe,

backed up by experimental evidence, suggests that there are an infinite

number of universes, an infinite number of copies of you and me,

and that the existence of the whole thing is inevitable.

No purpose, nothing special, you are because you have to be.

How does that make you feel?

Well, the wonderful thing is nobody knows,

nobody's worked it out yet, so the answer is up to you.

What do you think?