Mickey One

Hello.

My name is Stephen Hawking.

Physicist, cosmologist and something of a dreamer.

Although I cannot move

and I have to speak through a computer.

In my mind...

I am free!

Free to tour the universe

and tell the ultimate story.

The story of everything there ever was.

From the moment the cosmos began,

to the creation of our world and everything in it.

And beyond, to the far, far future.

And the end of the universe itself.

A journey through all of space and all of time.

Check it out.

I spend a lot of time thinking about the universe,

but I never get bored.

After all, it's a pretty extraordinary place.

This is the cosmos at a very large scale.

Each tiny point of light is an entire galaxy.

Each a cluster of as many as 400 billion individual stars.

This view of the universe is only possible due to the latest supercomputers.

I find it indescribably beautiful

uncountable billions of galaxies forming a vast web

stretching away in all directions.

What's more, I never get over the fact that within this massive universe

lies one perfectly ordinary spiral galaxy.

Inside that galaxy exists a commonplace yellow star.

Orbited by eight planets.

On one of those planets lives a species

that has only just worked out what a remarkable place the universe is.

Us.

We've discovered more about the cosmos in the last century

than in all previous human history.

Finally, we are solving the basic mysteries that have perplexed our ancestors

for at least 200,000 years.

What I like above all, is that the facts themselves

are both breathtakingly elegant and surprising.

We are living just as it dawns on us

that the earth and everything around us was made

by the stars.

Boiling furnaces of hydrogen gas, like our sun

made even the atoms in your eyelashes.

We've worked out that the universe is almost unimaginably ancient,

about 14 billion years old.

And that it will continue to exist for at least twice that long.

But without a doubt, the most remarkable fact of all

is that the entire enormous universe,

all the innumerable galaxies, even time and space,

and the forces of nature themselves

simply materialized out of...

nothing.

So now is a good time to be alive, I think.

We may only be an advanced breed of monkey

living on a small planet,

but we are able to contemplate the universe as a whole

which makes us very special.

My goal has always been simple,

to work out how the universe works and why it exists at all.

Luckily there are clues everywhere.

And the most important one is right above our heads.

Examine any patch of the night sky.

Even one as small as the head of a pin

and this is what you'll find.

A tiny part of the vast web of galaxies.

It's less than a millionth of what we can see of the cosmos

from our little planet.

But even this tiny sample is enough to find a clue.

The key to the past, the present...

and perhaps the future, too.

The clue is that, seen from earth, all these distant galaxies

are slightly red in color.

They appear almost as if we were looking through rose-tinted glasses.

It's this very redness that reveals how the universe was born.

And to show you why...

I need a straight road and a noisy car.

Listen to the sound as it passes by.

As the car approaches, the pitch of its engine rises.

As it goes away, the pitch of its engine... falls.

This phenomenon is called a Doppler shift.

And the exact same thing happens with light.

If our eyes were more sensitive to color,

we could see that the car is actually very slightly blue as it approaches.

And very slightly red as it goes away.

The same rules apply in space.

All distant galaxies are slightly red in color.

So by the exact same piece of basic physics,

they must all be moving away, too.

In fact, the whole universe is expanding,

in all directions,

getting bigger and bigger.

Like a balloon inflating.

I admit this sounds strange.

But to cosmologists, it's like winning the lottery.

Because to work out where the universe came from,

all we need to do is to stop time

and make it run in reverse.

Rewind far enough, and everything gets closer together

a lot closer together.

All the galaxies

in fact every single thing converges to a single point,

the start of everything, 13.7 billion years ago.

So it's quite simple really

Follow the clues and we can deduce that a very long time ago

the universe simply burst into existance,

an event called - the Big Bang.

But I'm afraid we have to stop a moment

Before we get carried away by fire and noise.

At the very beginning, the Big Bang actually happened in total darkness,

because light didn't exist yet.

To see it, we'd have needed some kind of cosmic night vision.

But even this, a view from the outside is impossible!

Again it sounds strange,

but space didn't exist then either.

So there was no outside.

The only place there was, was inside.

This early universe was a very strange thing indeed.

There's still much I'd dearly love to know about it.

But standard concepts of time or space don't really apply.

It was just a very tiny, ultra-hot fog of energy.

Then it expanded...

With a tremendous flash of radiation.

From smaller than an atom...

to about the size of an orange

in less than a trillionth of a second,

almost no time at all.

The universe simply inflated into existance.

Unfolding, unfurling...

getting bigger and cooler with every passing moment.

Within 100 seconds, it was as big as our Solar System

trillions of miles across.

While this was happening,

the pure energy of the cosmos began to cool and create matter

in the form of countless trillions of subatomic particles.

The first stuff there ever was.

Half these particles were made of matter

the same kind of stuff which makes us

The rest were made of the opposite of matter

stuff called antimatter.

When the two meet, they destroy each other in a flash of energy.

It seems as if building a universe is a pretty wasteful process.

Fortunately, there was just a bit more matter than antimatter

just one in a billion particles of stuff survived.

Which was lucky for us.

Because that residue, is what our present-day universe is made of.

You could say that we are made of the smoke of the Big Bang.

By the time the cosmos was 10 minutes old,

it was already thousands of light-years in diameter.

After that, everything spread out and cooled for about 330,000 years.

When finally the fog cleared, and the universe became visible.

So that's how everything got going

which I think is a pretty fantastic story

and probably much stranger

than anything our ancestors came up with by way of an explanation.

But the next thing that happened Well, that's pretty spectacular too.

This is the universe seen in extreme fast-forward

all 14 billion years in less than a minute.

It shows how the universe changed from a cloud of gas

into a place filled with perhaps 100 billion galaxies

swirling in a vast chaotic dance.

What I love to get people thinking about

is that all this had to be built atom by atom

celestial engineering on a spectacular scale.

So what drove this cosmic clockwork?

I'd say it was the force of gravity.

The idea of gravity was worked out by Sir Isaac Newton

who had the same job as me

here at Cambridge University back in the 17th century.

It supposedly dawned on him when an apple fell on his head.

The apple helped him realize that all objects attract each other.

And the greater the mass, the stronger the pull.

These apples are attracted to the earth.

And although you can't see it

the earth moves very slightly up towards the apples.

All things come together through the power of gravity.

Gravity was created in the Big Bang and has been at work ever since.

It's what keeps you, me and apples

stuck to the earth.

In the early universe, gravity had a much bigger role to play.

Right after the Big Bang, the universe was just gas.

Almost perfectly spread out throughout space.

Over the next 200 million years

gravity began to pull the gas back together

to produce the very first structures from which everything else would grow.

But even this very nearly didn't happen.

If it weren't for another stoke of cosmic luck,

there would be no you, no me,

no stars or planets, or anything at all.

We know this because in 1982, a group of scientists, including myself,

spent three solid weeks working it out.

Although the calculations were hard, demonstrating what we discovered is easy.

First, I need a nice flat floor, like this one for example.

This is the dining room in my college.

I'm going to fill the place with lots and lots of ball bearings.

These balls represent the matter of the early universe.

A thin gas spread out evenly across the vast cosmos.

Here's where luck comes in.

If they're all the same distance apart,

gravity pulls each ball the same amount in all directions.