All language subtitles for Order and Disorder S01E01 - Energy (2012) HDTV 1080p.ENG

How did humans acquire the power
to transform the planet like this?

Looking at the earth at night

reveals to us just how
successful we've been

in harnessing
and manipulating energy

and how important it is
to our existence.

Energy is vital to us all.

We use it to build the structures
that surround and protect us.

We use it to power our transport
and light our homes.

And even more crucially, energy
is essential for life itself.

Without the energy we get
from the food we eat, we'd die.

But what exactly is energy?

And what makes it so useful to us?

In attempting to answer
these questions,

scientists would come up with
a strange set of laws

that would link together everything,
from engines, to humans, to stars.

It turns out that energy,
so crucial to our daily lives

also helps us make sense
of the entire universe.

This film is the intriguing story

of how we discovered the rules
that drive the universe.

It is the story
of how we realised

that all forms of energy are
destined to degrade and fall apart.

To move from order to disorder.

It's the story
of how this amazing process

has been harnessed by the universe

to create everything
that we see around us.

Over the course of human history,

we've come up with
all sorts of different ways

of extracting energy
from our environment.

Everything from picking fruit,

to burning wood, to sailing boats,
to waterwheels.

But around 300 years ago,
something incredible happened.

Humans developed machines

that were capable of processing
extraordinary amounts of energy

to carry out
previously unimaginable tasks.

This happened thanks to many people
and for many different reasons,

but I'd like to begin this story

with one of the most
intriguing characters

in the history of science.

One of the first to attempt
to understand energy.

Gottfried Leibniz was a diplomat,
scientist, philosopher and genius.

He was forever trying
to understand the mechanisms

that made the universe work.

Leibniz like several
of his great contemporaries

was absolutely convinced
that the world we see around us

is a vast machine designed
by a powerful and wise person.

And if you could understand
how machines worked,

you could therefore
understand how the universe

and the principles that had been used
to make the universe worked as well.

So there was an extremely close
relationship for Leibniz

between theology and philosophy
on the one hand

and engineering
and mechanics on the other.

It was this relationship
between philosophy and engineering

that in 1676 would lead him
to investigate

what at first sight seemed to be
a very simple question.

What happens when objects collide?

This is was what Leibniz

and many of his contemporaries
were grappling with.

So when these two balls bump
into each other,

the movement of one
gets transferred to the other.

It's as though something's
been passed between them

and this that Leibniz
called the living force.

He thought of it as a stuff,

as a real physical substance that
gets exchanged during collisions.

Leibniz argued that the world
is a living machine

and that inside the machine,

there is a quantity of living force
put there by God at the Creation

that will stay the same forever.

So the amount of living force
in the world will be conserved.

The puzzle was to define it.

Leibnitz would soon find
a simple mathematical way

to describe the living force.

But he would also see
something else.

EXPLOSION

He realised that in gunpowder,
fire and steam,

his living force was being released
in violent and powerful ways.

EXPLOSION

If this could be harnessed,

it could give humankind
unimaginable power.

Leibniz would soon
become fascinated

with ways of capturing
the living force.

A prolific letter writer,
Leibniz struck up correspondence

with a young French scientist
called Denis Papin.

As they corresponded,
Leibniz and Papin realised

the living force released
in certain situations

could indeed be harnessed.

Heat could be converted in
to some form of useful action.

But how far
could this idea be taken?

Papin was in no doubt.

This is an extract
from his letter to Leibniz...

"I can assure you
that the more I go forward,

"the more I find reason to think
highly of this invention,

"which in theory, may augment
the powers of man to infinity.

"But in practice, I believe
I can say without exaggeration,

"that one man by this means

"will be able to do as much as
100 others can do without it."

Now, you might expect me
at this point to tell you

that Leibniz and Papin
changed the world forever.

Well, they hadn't.

Their ideas had been profound
and far reaching, yes,

but they hadn't really
moved things forward.

For that, you need something
much more tangible.

You need innovation, industry.

You need countless skilled workers
and craftsmen

who are going to apply
these ideas,

to experiment with them
in novel and new ways.

Well, in the century
that followed Leibniz and Papin,

this would take place
in the most dramatic way imaginable.

150 years after Leibniz
and Papin's discussions,

the living force had been
harnessed in spectacular ways.

The machines they dreamed of
had become a reality.

Steam engines were now the cutting
edge of 19th century technology.

If you look at steps in civilisation,

then one great step was the steam
engine, because it replaced muscle,

animal muscle, including our muscle,
by steam power.

And the steam power
was effectively limitless

and hugely important to doing
almost unimaginable things.

But steam technology would do more
than just transform human society.

It would uncover the truth
about what Leibniz had called

the living force
and reveal new insights

about the workings of our universe.

This is Crossness
in south-east London.

It's an incredible
industrial cathedral,

home to some of the most impressive
Victorian steam engines ever built.

Constructed in 1854,
Crossness houses four huge engines

that once required
5,000 tonnes of coal each year

to drive their 47-tonne beams.

Everything about this place
seems to have been built to impress.

From the lavish ironwork -

the grand pillars like something
out of a Greek or Roman temple.

It's the kind of effort
you'd think would be lavished

on a luxury ocean liner
for the rich and famous.

And yet this place
was built to process sewage.

Although only a few workers
and engineers would see inside it,

steam had become

such a vital part of Britain's power
and economic prosperity

that it was afforded
almost religious respect.

But for all the great success
and immense power

that engines were
bestowing on their creators

there was still a great deal
of confusion and mystery

surrounding exactly
how and why they worked.

In particular questions like,
"How efficient could they be made?"

"Were there limits to their power?"

Ultimately, people wanted to know

just what might it be possible
to achieve with steam.

The reason these questions persisted
was simple - almost no-one

had understood the fundamental
nature of the steam engine.

Very few were aware of the cosmic
principle which underpinned it.

These great lumbering machines we
think of as the early steam engines

actually were the seed
of understanding

of everything
that goes on in the universe.

As unlikely as it sounds,

steam engines held within them
the secrets of the cosmos.

This is the Chateau
de Vincennes in Paris.

Events here would motivate one man's
journey to uncover the cosmic truth

about the steam engine,
and help to create a new science.

The science of heat and motion.
Thermo-dynamics.

In March 1814,
during the Napoleonic wars,

when Napoleon and his armies
where fighting elsewhere,

Paris itself
came under sustained attack

from the combined forces
of Russia, Prussia and Austria.

Citizens were deployed around
key locations to protect them.

This chateau was being defended
by a group of inexperienced students

who were forced to retreat
under sustained artillery fire.

One of them was a brilliant
young scientist and soldier.

His name was
Nicolas Leonard Sadi Carnot

and the humiliation
he felt personally

would drive him and motivate him

to uncover a profound insight
into how all engines work.

Carnot came from
a highly-respected military family.

After the French defeat here
and elsewhere around Europe,

he became determined
to reclaim French pride.

What really bothered Carnot
was the technological superiority

that France's enemies
seemed to possess.

And Britain, in particular,
had this huge advantage

both militarily and economically

because of its mastery
of steam power.

So Carnot vowed to really
understand how steam engines work

and use that knowledge
for the benefit of France.

He says absolutely explicitly
that if you could take away

steam engines from Britain

then the British Empire
would collapse.

And he's writing in the wake
of French military defeat

and he proposes to analyse,

literally,
the source of British power

by analysing the way in which
fire and heat engines work.

Living on half-pay
with his brother Hippolyte

in a small apartment in Paris,

in 1824 Carnot wrote
the now legendary

Reflections On
The Motive Power Of Fire.

In just under 60 pages,

he developed and abstracted
the fundamental way

in which all heat engines work.

Carnot saw that all heat engines

comprised of a hot source
in cooler surroundings.

Now, Carnot believed heat
was some kind of substance

that would flow like water
from the hot to the cool.

And just like water
falling from a height

the flow of heat could be tapped
to do useful work.

Carnot's crucial insight

was to show that to make
any heat engine more efficient

all you had to do was to increase
the difference in temperature

between the heat source
and cooler surroundings.

This idea has guided
engineers for 200 years.

Ultimately, a car engine is
more efficient than a steam engine

because it runs
at a much hotter temperature.

Jet engines are more efficient still

thanks to the incredible
temperatures they can run at.

Carnot had revealed

that heat engines
weren't just a clever invention.

They were tapping into
a deeper property of nature.

They were exploiting
the flow of energy

between hot and cold.

Carnot had glimpsed the true nature
of heat engines and, in the process,

begun a new branch of science.

But he would never see the impact
his idea would have on the world.

In 1832, a cholera epidemic
spread through Paris.

It was so severe,
it would kill almost 19,000 people.

Now, back then, there was
no real scientific understanding

of how the disease spread,
so it must have been terrifying.

Carnot undaunted by the risks,

decided to study and document
the spread of the disease.

But, unfortunately, he contracted it
himself and was dead a day later.

He was just 36 years old.

A lot of his precious
scientific papers were burned

to stop the spread of the contagion

and his ideas
fell into temporary obscurity.

It seems the world
wasn't quite ready for Carnot.

Carnot had made
the first great contribution

to the science of thermodynamics.

But as the 19th century progressed
the study of heat, motion and energy

began to grip
the wider scientific community.

Soon, it was realised
these ideas could do much more

than simply explain
how heat engines worked.

Just as Leibniz had suspected
with his notion of living force,

these ideas were applicable
on a much grander scale.

By the mid 19th century,

scientists and engineers
had worked out very precisely

how different forms of energy
relate to each other.

They measured how much of a
particular kind of energy is needed

to make a certain amount
of a different kind.

Let me give you an example.

The amount of energy
needed to heat 30ml of water

by one degree centigrade

is the same as the amount
of energy needed

to lift this 12.5kg weight
by one metre.

The deeper point here
that people realised

was that although mechanical work
and heat may seem very different,

they are, in fact, both facets
of the same thing - energy.

This idea would come to be known
as the first law of thermodynamics.

The first law reveals that energy
is never created or destroyed.

It just changes
from one form to another.

19th Century scientists realised
this meant the total energy

of the entire universe
is actually fixed.

Amazingly,
there's a set amount of energy

that just changes
into many different forms.

So, in a steam engine,
energy isn't created -

it's just changed
from heat into mechanical work.

But impressive though the first law
is, it begged an enormous question -

what exactly is going on when one
form of energy changes into another?

In fact, why does it do it at all?

The answer would, in part, be found
by German scientist Rudolf Clausius.

And it would form the basis
what would become known

as the second law of thermodynamics.

Rudolf Clausius was
a brilliant German physics student

from Pomerania

who studied in Berlin

and at a ridiculously young age
became a very brilliant professor

in Berlin and then in Zurich

at the new technology university
set up there in Switzerland.

In the 1850s and 60s,
Clausius offered what was really

the first, coherent,
full-blown, mathematical analysis

of how thermodynamics works.

Clausius realised
that not only was there

a fixed amount of energy
in the universe

but that the energy seemed to be
following a very strict rule.

Put simply,
energy in the form of heat

always moved
in one particular direction.

This insight of his is

in fact one of the most important
ideas in the whole of science.

As Clausius put it,

"Heat cannot of itself pass
from a colder to a hotter body".

This is a very intuitive idea.

If left alone, this hot mug of tea
will always cool down.

What this means is that heat
will pass from the hot mug

say to my hand and then again
from my hand to my chest.

This might seem completely obvious
but it was a crucial insight.

This might seem completely obvious
but it was a crucial insight.

The flow of heat was a one-way
process that seemed to be built

very fundamentally into the workings
of the entire universe.

Of course, objects can get hotter

but you always need to do something
to them to make this happen.

Left alone, energy seems to always
go from being concentrated

to being dispersed.

One of my favourite statements
in science was made

by the biochemist called
Albert St George who said that,

"Science is all about seeing
what everyone else has seen,

"but thinking
what no-one else has thought."

And he, Rudolf Clausius,
looked at the everyday world

and saw what everyone else had seen,

that heat does not flow spontaneously
from a cold body to a hot body.

It always goes the other way.

But he didn't just say,
"Ah, I see that."

He actually sat down
and thought about it.

Clausius brought together
all these ideas about how energy

is transferred and put them
into mathematical context.

It could be summarised
by this equation.

Now, what Clausius did was introduce
a new quantity he called entropy.

This letter S.

Basically, what it's saying
in the context of this equation

is that as heat is transferred
from hotter to colder bodies,

entropy always increases.

Entropy seemed to be a measure of
how heat dissipates or spreads out.

As hot things cool,
their entropy increases.

It appeared to Clausius
that in any isolated system

this process would be irreversible.

Clausius was so confident
about his mathematics

that he figured out
that this irreversible process

was going on out there
in the wider cosmos.

He speculated that the entropy
of the entire universe

had to be increasing
toward a maximum

and there was nothing
we could do to avoid this.

This idea became known as
the second law of thermodynamics

and it turned out to be
stranger, and more beautiful,

more universal than anything
that Clausius could have imagined.

The second law of thermodynamics
seemed to say that all things

that gave off heat were,
in some way, connected together.

All things that gave off heat
were part of an irreversible process

that was happening everywhere.

A process of spreading out
and dispersing.

A process of increasing entropy.

It seemed that, somehow,
the universe shared the same fate

as a cup of tea.

The wonderful thing
about the Victorian scientists

is that they could
make these great leaps

and they could see that their study
of a thermometer in a beaker

actually could be transferred...
could be extrapolated,

could be enlarged
to encompass the whole universe.

Despite the successes
of thermodynamics,

in the middle of the 19th century,

there was great debate
and confusion about the subject.

What exactly was this
strange thing called entropy

and why was it always increasing?

Answering this question would take
an incredible intellectual leap

but it would end up revealing
the truth about energy

and the many forms
of order and disorder

we see in the universe around us.

Many scientists would tackle
the mysterious concept of entropy.

But one more than any other
would shed light on the truth.

He'd show what entropy really was

and why, over time,
it always must increase.

His name was Ludwig Boltzmann

and he was one science's
true revolutionaries.

Boltzmann had been born
in Vienna in 1844.

It was a world of scientific
and cultural certainty.

But Boltzmann took little notice

of the entrenched beliefs
of his contemporaries.

To him, the physical world

was something best explored
with an open mind.

Boltzmann wasn't
your stereotypical scientist.

In fact, he had
the kind of temperament

most people might associate
with great artists.

He was ruthlessly logical
and analytical, yes,

but while working, he'd go through
periods of intense emotion

followed by terrible depressions

which would leave him
completely unable to think clearly.

He had terrible

mental crises and breakdowns

in which he really thought that the
world was coming apart at the seams

and yet these were also accompanied

by some of the most profound insights
into the nature of our world.

Outside of mathematics,
Boltzmann was passionate about music

and was captivated by the grand
and dramatic operas of Wagner

and the raw emotion of Beethoven.

He was a brilliant pianist

and could lose himself for hours in
the works of his favourite composers

just as he could lose himself
in deep mathematical theories.

MUSIC: Beethoven's 5th Symphony -
First Movement.

Boltzmann was a scientist
guided by his emotions and instinct

and also by his belief
in the ability of mathematics

to unlock the secrets of nature.

It was these traits
that would lead him to become

one of the champions of a shocking
and controversial new theory.

One that would describe reality
at the very smallest scales.

Far smaller than anything
we could see with the naked eye.

During the second half of the 19th
century, a small group of scientists

began speculating that,
at the smallest scales,

the universe
might operate very differently

to our everyday experiences.

If you could look close enough,
it seemed possible that the universe

might be made of tiny,
hard particles, in constant motion.

Viewed in terms of atoms

heat would suddenly become
a much less mysterious concept.

Boltzmann and others saw
that if an object was hot

it simply meant that its atoms
were moving about more rapidly.

Viewing the world as atoms seemed
to be an immensely powerful idea.

But this picture of the universe

had one seemingly
insurmountable problem.

How could trillions
and trillions of atoms,

even in a tiny volume of gas,
ever be studied?

How could we come up
with mathematical equations

to describe all of this?

After all, atoms are constantly
bumping into each other,

changing direction and speed,
and there are just so many of them.

It seemed almost
an impossible problem.

But then Boltzmann
saw there was a way.

Boltzmann saw
more clearly than anyone

that for physics to explain
this new strata of reality

it had to abandon certainty.

Instead of trying to understand
and measure the exact movements

of each individual atom, Boltzmann
saw you could build working theories

simply by using the probability
that atoms would be travelling

at certain speeds
and in certain directions.

Boltzmann had transported himself
inside matter.

He had imagined a world
beneath our everyday reality

and found a mathematics
to describe it.

It would be here at this scale
that Boltzmann would one day manage

to unlock energy's deepest secret -

despite the widespread
hostility to his theories.

Boltzmann's ideas were
highly, highly controversial.

And you have to remember that today
we take atoms for granted.

But the reason we take atoms
for granted is precisely because

Boltzmann's mathematics married up
so beautifully with experiments.

One of the most surprising aspects
of this story is that

many of Boltzmann's contemporaries
viewed his ideas about atoms

with intense hostility.

Today the existence of atoms,

the idea that all matter
is composed of tiny particles,

is something
we accept without question.

But back in Boltzmann's time

there were notable, eminent
physicists who just didn't buy it.

Why would they?

No-one had ever seen an atom
and probably no-one ever would.

How could these particles
be considered as real?

After one of Boltzmann's lectures
on atomic theory in Vienna

the great Austrian physicist
Ernst Mach stood up

and said simply,
"I don't believe that atoms exist!"

It was both cutting and dismissive.

And for such a comment to come
from a highly regarded scientist

like Ernst Mach,
it would have been doubly hurtful.

They argued that,
"No, atoms don't exist."

They're names, labels,

convenient fictions,
calculating devices.

They don't really exist.
We can't observe them.

No-one's ever seen one.

And for that reason, so Boltzmann's
critics said, he was a fantasist.

But Boltzmann was right.

He had peered deeper into reality
than anyone else had dared,

and seen that the universe could be
built from the atomic hypothesis

and understood through
the mathematics of probability.

The foundations and certainty
of 19th century science

were beginning to crumble.

As Boltzmann stared into
his brave new world of atoms

he began to realise his new vision
of the universe contained within it

an explanation to one
of the biggest mysteries in science.

Boltzmann saw atoms could reveal why
the second law of thermodynamics

was true, why nature was
engaged in an irreversible process.

Atoms had the power to reveal
what entropy really was

and why it must always increase.

Boltzmann understood
that all objects - these walls,

you, me, the air in this room, are
made up of much tinier constituents.

Basically, everything
we see is an assembly

of trillions and trillions
of atoms and molecules.

And this was the key to his insight
about entropy and the second law.

Boltzmann saw
what Clausius could not.

The real reason why a hot object
left alone will always cool down.

Imagine a lump of hot metal.

The atoms inside it
are jostling around.

But as they jostle, the atoms
at the edge of the object

transfer some of their energy to the
atoms on the surface of the table.

These atoms then bump into
their neighbours, and in this way,

the heat energy slowly and very
naturally spreads out and disperses.

The whole system has gone from
being in a special, ordered state

with all the energy
concentrated in one place,

to a disordered state

where the same amount of energy is
distributed amongst many more atoms.

Boltzmann's brilliant mind

saw this whole process
could be described mathematically.

Boltzmann's great
contribution was that,

although we can talk
in rather sort of casual terms,

about things getting worse,
and disorder increases,

the great contribution of Boltzmann
is that he could put numbers to it.

So he was able to derive
a formula which enabled you

to calculate
the disorder of the system.

This is Boltzmann's famous equation.

It would be his enduring
contribution to science,

so much so, it was engraved
on his tombstone in Vienna.

What this equation means in essence

is there are many more ways for
things to be messy and disordered

than there are for them
to be tidy and ordered.

That's why, left to itself, the
universe will always get messier.

Things will move
from order to disorder.

It's a law that applies
to everything

from a dropped jug
to a burning star.

A hot cup of tea to the products
that we consume every day.

All of this is an expression
of the universe's tendency

to move from order to disorder.

Disorder is the fate of everything.

Clausius had shown
that something he called entropy

was getting bigger all the time.

Now Boltzmann had revealed
what this really meant -

entropy was in fact
a measure of the disorder of things.

Energy is crumbling away.

It's crumbling away now as we speak.

So the second law is all about
entropy increasing.

It's just a technical way
of saying things get worse.

Boltzmann's passionate
and romantic sensibility

and his belief
in the power mathematics

had led him to one of
the most important discoveries

in the history of science.

But those very same intense emotions

had a dark and ultimately
self-destructive side.

Throughout his life

Boltzmann had been prone
to severe bouts of depression.

Sometimes these were induced
by the criticisms of his theories

and sometimes they just happened.

In 1906, he was forced to take
a break from his studies in Vienna

during a particularly bad episode.

In September 1906, Boltzmann
and his family were on holiday

in Duino, near Trieste in Italy.

While his wife and family
were out at the beach,

Boltzmann hanged himself,

bringing his short time
in our universe to an abrupt end.

Perhaps the saddest aspect
of Boltzmann's story

is that, within a few short years
of his death,

his ideas that had been attacked
and ridiculed during his life,

were finally accepted.

What's more, they became
the new scientific orthodoxy.

In the end there is no escaping
entropy - it is the ultimate move

from order, to decay and disorder,
that rules us all.

Boltzmann's equation contains within
it the mortality of everything

from a china jug to a human life
to the universe itself.

The process of change
and degradation is unavoidable.

The second law says the universe
itself must one day

reach a point of maximum entropy,
maximum disorder.

The universe itself
must one day die.

If everything degrades,
if everything becomes disordered

you might be wondering
how is it that WE exist.

How exactly did the universe
manage to create

the exquisite complexity
and structure of life on earth?

Contrary to what you might think

it's precisely because of
the second law that all this exists.

The great disordering of the cosmos
gives rise to its complexity.

It's possible to harness
the natural flow

from order to disorder,
to tap into the process

and generate something new, to
create new order and new structure.

It's what the early steam pioneers
had unwittingly hit upon

with their engines

and it's what makes everything
we deem special in our world -

from this car, to buildings, to
works of art, even to life itself.

The engine of my car,
like all engines,

is designed to exploit
the second law.

It starts out with something
nice and ordered like this petrol -

stuffed full of energy.

But when it is ignited in the engine
it turns this compact liquid

into a mixture of gases
2,000 times greater in volume -

not to mention dumping heat
and sound into the environment.

It's turning order to disorder.

What's so spectacularly clever
about my car

is that it can harness
that dissipating energy.

It can siphon off a small bit of it

and use it to run
a more ordered process -

like driving the pistons which turn
the wheels. That's what engines do.

They tap into that flow
from order to disorder

and do something useful.

But it's not just cars.

Evolution has designed
our bodies to work

thanks to the very same principle.

If I eat this chocolate bar

packed full of
nice, ordered energy,

my body processes it and turns it
into more disordered energy

but powers itself off the proceeds.

Both cars and humans
power themselves by tapping into

the great cosmic flow
from order to disorder.

Although overall the world
is falling apart in disorder

it is doing it
in a seriously interesting way.

It's like a waterfall
that is rushing down,

but the waterfall throws up
a spray of structure

and that spray of structure might be
you or me or a daffodil or whatever.

So you can see that
the unwinding of the universe,

this collapse into disorder,
can in fact be constructive.

Steam engines,

power stations,

life on earth -

all of these things
harness the cosmic flow

from order to disorder.

The reason the earth now looks
the way it does

is because we've learnt
to harness the disintegrating energy

of the universe to maintain and
improve our small pocket of order.

But as humankind has evolved,

we've had to find new pieces
of concentrated energy

we can break down to drive
the ever more demanding

construction of our technologies,
our cities, and our society.

From food, to wood, to fossil fuels
over human history

we've discovered ever more
concentrated forms of energy

to unlock in order to flourish.

Now in the 21st century
we're on the cusp of harnessing

the ultimate form
of concentrated energy.

The stuff that powers the sun.

Hydrogen.

This is the Cullham Centre
for Fusion Energy in Oxford

and at this facility
they're attempting to recreate

a star here on earth.

But as you might imagine

creating and containing a small star

is not an easy process.

It requires many hundreds of people

and some extremely ingenious
technology.

This machine is called a tokamak
and it's designed to extract

an ancient type
of highly-concentrated energy.

The ordered energy
of hydrogen atoms.

These tiny packets of energy
were forged in the early universe,

just three minutes after
the moment of creation itself.

Now using the tokamak we can extract
the concentrated energy

contained in these atoms
by fusing them together.

Inside the tokamak machine
two types of hydrogen gas,

deuterium and tritium,

are mixed together into
a super hot state called a plasma.

Now, when running this plasma
can reach the incredible temperature

of 150 million degrees!

Large magnets in the walls
of the tokamak contain the plasma

and stop it touching the sides
where it can cool down.

When it gets hot enough
the two types of hydrogen atoms

fuse together to form helium
and spit out a neutron.

These neutrons fly
out of the plasma

and hit the walls of the tokamak,
but they carry energy

and the hope is that this energy can
one day be used to heat up water,

turn it into steam to drive
a turbine and generate electricity.

Essentially for a brief moment
inside the tokamak

a small doughnut-shaped star
is created.

The problem is
it's extremely difficult to sustain

the fusion reaction for long enough
to harvest energy from it.

And that's what the scientists
at Cullham are working to perfect.

It's a boundary between
physics and engineering.

How do we hold on to this very
hot thing which is the plasma?

And how do we optimise the way
in the performance of this plasma?

So what we want is the particles
to stay in there as long as possible

to maximise their chance
of hitting each other.

We are trying to push this
to the limit

with what we have available
in this machine.

And whatever we can learn
to understand this plasma better

will allow us to design
a better machine in the future.

Although it happens several times
a day... Oh, here we go.

The scientists here
all gather round the screens.

OK, it's about to come on.

What the tokamak is doing

is mining the fertile ashes
of the big bang.

Extracting concentrated energy
captured at the beginning of time.

As hydrogen is the most
abundant element in the universe,

if future machines
can sustain fusion reactions,

they offer us the possibility
of almost unlimited energy.

From a science that began
as the by-product of questions

about steam engines,

thermodynamics has had a
staggering impact on all our lives.

It has shown us why we must consume
concentrated energy to stay alive

and has revealed to us how the
universe itself is likely to end.

Looking at the earth at night
reveals how

one seemingly simple idea
transformed the planet.

Over the past 300 years, we've
developed ever more ingenious ways

to harness the concentrated energy
from the world around us.

But all our efforts and achievements
are quite insignificant

when viewed from the perspective
of the wider universe.

As far as it's concerned all
we are doing is trying to preserve

this tiny pocket of order
in a cosmos that's falling apart.

Although we can never escape
our ultimate fate

the laws of physics have allowed us

this brief, beautiful,
creative moment

in the great cosmic unwinding.

My hope is that by understanding
the universe in ever greater detail

we can stretch this moment
for many millions

maybe even billions of years
to come.

The concept of information
is a very strange one,

it's actually a very difficult idea
to get your head round.

But in the journey
to try and understand it

scientists would discover that

information is actually
a fundamental part of our universe.