Human Universe
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?
There is air and water here on Earth
So life come into existence here
God created us so we can help others
We have come here to suffer our sins
I feel we all exist for a reason
for ourselves or someone else
A scientific answer to this question
may not be far away.
HUMAN UNIVERSE
Part Two Why are we here?
Edited Version
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.
Brahmaswam Madham School Kerala
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.
I need to be a Priest
I am intersted in that
I'm intersted in other things also
What I like most is cricket
Shankar is one of 40 students here,
all of them training for the Hindu priesthood.
Their day follows a strict routine starting at 5am.
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.
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 themselves are later than creation
So who knows truly whence it has arisen?
"The gods are later than creation."
I think that's a remarkable sentence.
It displays real intellectual rigour and honesty.
The gods are later than creation
So who knows truly whence it has arisen?
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.
Chambal River
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.
Bera Rajasthan
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.
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.
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.
Bhand Devra Temple Baran
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.
Pushkar Rajasthan
In Pushkar they have quite a tradition of camel racing.
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?
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.
Kyoto Japan
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 Japanese sword is totally unique
it's often said to be the symbol of Japanese mentality
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.
Quenching is the most nerve wracking (part) for a swordsmith
as he has to put his soul into the metal
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. North Pacific
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?
For small creatures such as we,
the vastness is bearable only through love
For small creatures such as we, the vastness is bearable only through love Carl Sagan
End