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Human Universe

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

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..yet we are matter
with curiosity,

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we ask questions.

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And, in the private world
of our minds,

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one particular question burns...

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Why are we here?

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There is air and water here on Earth

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So life come into existence here

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God created us so we can help others

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We have come here
to suffer our sins

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I feel we all exist
for a reason

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for ourselves or someone else

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A scientific answer to this question

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may not be far away.

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HUMAN UNIVERSE

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Part Two
Why are we here?

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Edited Version

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If the existence of any one of us
is singled out

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

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looks like pure chance.

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Like any particular individual,

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baby Shurik was born into this world as the
culmination of a chain of apparent coincidences.

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A chain so long that,
at first sight,

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it looks highly improbable.

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

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

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and their parents too...

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and generations of ancestors
before that.

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But don't stop there.

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

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..to our planet
and its position in space.

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

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

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

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for the temperatures on its surface
to be just right

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to permit liquid water to exist.

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

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

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And this seeming luck
continues beyond our solar system.

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

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for stars and galaxies to form.

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And within those stars, the forces
of nature are just

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

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carbon, oxygen and iron,
in their cores.

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If you trace it right back,

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

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they seem almost
infinitesimally small.

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Why are we here?

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Is our existence merely accidental?

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And if we are just happy accidents,

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then what about the universe?

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Is its form, its nature,
its very existence

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also accidental?

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

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

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

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Brahmaswam Madham School
Kerala

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Shankar is 12 years old

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and has lived at this school
since he was eight.

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He sees his parents only every
three months...

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But, to him, it's worth it

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because he has a singular life ahead
of him as a Hindu priest, or Brahman.

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I need to be a Priest

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I am intersted in that

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I'm intersted in other things also

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What I like most is cricket

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Shankar is one of 40 students here,

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all of them
training for the Hindu priesthood.

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Their day follows a strict routine
starting at 5am.

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Almost every day the students chant
between seven in the morning

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and seven at night.

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They're chanting Vedas,
ancient verses which date back

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4,000 years, containing
the poetry and myths

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on which Hinduism is based.

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These religious verses hold
some unexpected thoughts.

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They contain the concept of zero

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and they touch on the notion
of infinity.

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And they use mathematical
concepts such as Pi, square roots

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and Pythagoras' theorem.

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

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you can find a very
interesting thought.

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It addresses a crucial question
about the formation of the universe.

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The gods themselves
are later than creation

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So who knows truly
whence it has arisen?

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"The gods are later than creation."

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I think that's
a remarkable sentence.

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It displays real intellectual
rigour and honesty.

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The gods are later than creation

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So who knows truly
whence it has arisen?

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

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"Well, all this exists because it was willed
into existence "merely by some kind of deity."

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It's reasonable to then ask
the question,

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

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

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

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that kind of thinking which is
really what you might say

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

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

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grand questions like
"Why are we here?"

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we have to begin with "how".

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

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

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"Why is it that when you let
something go

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"it falls to the ground?"

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

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

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tiny, small regularities,

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

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Through that process
we've been led to

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an intellectual framework
that maybe allows us

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to answer questions about the
very origin of reality itself.

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From the marketplace
to outer space,

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

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Galileo said nature is a book

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written in the language
of mathematics.

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

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the more you see it...

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..everywhere.

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Chambal River

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Rivers meander through the landscape
in a seemingly random way

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and if you just look at a few turns

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then they will be random.

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The river might change its course

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because of some geology,
a big rock formation.

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

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say tens or hundreds of kilometres,

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

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a pattern emerges,
there's order there.

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

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the meander you can see here,

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and the mathematical relationship,

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

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If I measure the wavelength
of the meander,

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which is just the length
between the point

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where the river starts to turn

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

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

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

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then it's something
like one centimetre,

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so the ratio of the wave length

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

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

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so not just one bend
but hundreds of bends,

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you'll find that that ratio
is always somewhere

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between about 10 and 14.

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

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this isn't a special river.

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If you look at any river
on the planet,

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no matter how small or wide,

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

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There's obviously some
pattern there,

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it reflects something fundamental
about the way that fluids

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flow across the surface
of Planet Earth.

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And this rule can even be
seen on other planets.

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On Mars, the rivers have long
since dried up,

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but the arid river beds show
the same meandering pattern.

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

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

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But even here the same ratio
appears to exist.

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This rule seems to hold true
for every river

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found across the solar system.

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Bera
Rajasthan

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

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to living things,

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even the most exotic
and elusive of creatures.

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

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

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

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"and the Hartebeest lived there,

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"but the Leopard,
he was the 'sclusivest

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"sandiest-yellowish-brownest
of them all."

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

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

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he used to go hunting
with the Leopard.

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

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very successful, it had a plain,
sandy coat,

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whereas all the other animals
had camouflage.

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

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So he took his fingers and his thumb
and he pressed

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into the Leopard's coat to give it
that distinctive

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five-pointed camouflage pattern.

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

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

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No-one disputes the reason
why leopards have spots,

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they evolved as camouflage.

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

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Let's have a look.

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Fantastic.

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

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

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then you turn round to see it again,

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it's very, very difficult
to find it.

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You've essentially got to wait
till it moves.

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It just shows you
the effectiveness of camouflage.

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How does that complex camouflage
emerge from the millions

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of separate cells
across the leopard's skin?

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Measure out...
..a precise amount of indicator.

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Then I'm just going to add it in.

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It turns out that complex patterns
can emerge from simple ingredients.

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And, mix them up.

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

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There, you see?

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And now can you see the colour
coming back,

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fading back in?

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It's not the usual chemical
reaction,

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

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which is what all chemists love.

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00:19:25,600 --> 00:19:29,080
This reaction is continually
oscillating

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backwards and forwards.

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So we started with the simplest
of ingredients,

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mixed them together

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and they reacted in such a way

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that complexity,

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that pattern, emerged
from the underlying simplicity.

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00:19:47,120 --> 00:19:49,920
A similar process
happens in living things.

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00:19:50,120 --> 00:19:51,840
When the leopard
was still an embryo,

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00:19:52,040 --> 00:19:55,880
it's thought that two competing
chemicals, washing over the skin,

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created the distinctive spots.

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00:19:58,560 --> 00:20:00,640
So if you have a sandy background,

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then you can imagine
one of these chemicals

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that causes or stimulates
pigment to appear,

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so as it grows you get a dark spot.

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

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It grows again, you get a dark spot

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and returns to the sandy background.

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

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

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Scientists get very excited
when they discover
an explanation like this

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

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and that's that complexity masks
an underlying simplicity.

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All the intricacy that we
see across the natural world

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emerges from a few simple laws.

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The meander of a river
and a leopard's spots

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are just two examples
of patterns in nature,

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but there are countless more.

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By looking carefully
at the patterns in nature

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and trying to understand
their origin,

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00:21:21,560 --> 00:21:24,080
that's what Copernicus and Kepler

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00:21:24,280 --> 00:21:26,600
and Newton and Einstein and Galileo

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00:21:26,800 --> 00:21:31,080
and Curie and Dirac and Feynman and
a thousand others have discovered.

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00:21:32,360 --> 00:21:34,520
There are regularities in nature,

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00:21:34,720 --> 00:21:37,720
there are patterns as far
as the eye can see,

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00:21:37,920 --> 00:21:40,960
on every scale from atoms
to galaxies

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00:21:41,160 --> 00:21:49,880
and those patterns are a reflection of the simplicity
and beauty of the underlying laws of nature.

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A blueprint for creation does exist,

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a scientific one.

248
00:22:26,640 --> 00:22:31,360
But how do the laws of physics
explain the existence of human beings?

249
00:22:31,560 --> 00:22:38,063
How, or why, did atoms come together
to form us in particular?

250
00:22:55,560 --> 00:22:58,920
The game of cricket is
unfathomable to some

251
00:22:59,120 --> 00:23:02,480
but to those who understand it
it's bewitching.

252
00:23:05,200 --> 00:23:08,640
I really love it,
I just can't express it...

253
00:23:08,840 --> 00:23:11,440
I...I don't express it in words.

254
00:23:11,640 --> 00:23:14,040
My dream is to play for India.

255
00:23:14,240 --> 00:23:17,600
This is what I've been aiming for
since my childhood.

256
00:23:20,600 --> 00:23:22,680
Today Subitu Bose and his team-mates

257
00:23:22,880 --> 00:23:25,880
are playing against rivals
Neerja Modi School.

258
00:23:33,400 --> 00:23:36,480
Cricket is based on a set of rules

259
00:23:36,680 --> 00:23:40,080
and they haven't altered
significantly since the 1800s.

260
00:23:48,720 --> 00:23:54,560
But, despite the existence of these
rules, no match is ever predictable.

261
00:24:00,960 --> 00:24:03,640
Take, for instance, the ball.

262
00:24:05,840 --> 00:24:09,400
Climate makes a big difference
to its swing,

263
00:24:09,600 --> 00:24:11,500
dew picked up from wet grass

264
00:24:11,700 --> 00:24:13,600
or scuffing from dry ground...

265
00:24:18,840 --> 00:24:20,960
..not to mention how it's bowled.

266
00:24:25,400 --> 00:24:27,240
And then there's the bat.

267
00:24:30,160 --> 00:24:33,640
Each batsman has a preference
for a bat of a particular weight

268
00:24:33,840 --> 00:24:35,800
and that will affect his stroke.

269
00:24:37,480 --> 00:24:41,440
Not forgetting the temperament
of each player,

270
00:24:41,640 --> 00:24:43,500
the mood of the umpire

271
00:24:43,700 --> 00:24:45,560
and the mood of the crowd.

272
00:24:52,440 --> 00:24:55,880
When you get so many variables,
the number of possibilities

273
00:24:56,080 --> 00:25:00,280
becomes enormous
and yet all this complexity

274
00:25:00,480 --> 00:25:03,360
emerged from a set of fixed rules.

275
00:25:08,400 --> 00:25:11,480
A game of cricket is played out
according to a set of simple laws

276
00:25:11,680 --> 00:25:13,480
and so it is for the universe,

277
00:25:13,680 --> 00:25:16,560
and here are the laws
of the universe.

278
00:25:16,760 --> 00:25:18,880
This is the standard model of
particle physics

279
00:25:19,080 --> 00:25:22,360
and this is Einstein's General
Theory of Relativity

280
00:25:22,560 --> 00:25:25,000
and you can fit them
easily on a scorecard.

281
00:25:25,200 --> 00:25:27,080
And here are the laws of cricket

282
00:25:27,280 --> 00:25:30,880
and it has to be said,
at least in this notation,

283
00:25:31,080 --> 00:25:34,680
that cricket is more complicated
than the universe.

284
00:25:34,880 --> 00:25:36,840
But even given these simple laws,

285
00:25:37,040 --> 00:25:40,400
the number of ways that both games
can play out

286
00:25:40,600 --> 00:25:42,560
is effectively infinite.

287
00:25:42,760 --> 00:25:47,040
So the laws do not make
the outcome predictable.

288
00:25:50,400 --> 00:25:53,640
But all we really
care about is the outcome.

289
00:25:53,840 --> 00:25:56,880
In the case of the game
of cricket - who won?

290
00:25:57,080 --> 00:26:01,000
In the case of the game
of the universe - we exist.

291
00:26:01,200 --> 00:26:02,400
And for the cricket match,

292
00:26:02,600 --> 00:26:07,520
the result could have turned on the
tiniest, most insignificant little event,

293
00:26:07,720 --> 00:26:10,580
the way the ball gripped the pitch
and deflected off

294
00:26:10,780 --> 00:26:13,640
a couple of blades of grass,
clipped the edge of the bat

295
00:26:13,840 --> 00:26:15,920
and was caught
by the wicketkeeper.

296
00:26:16,120 --> 00:26:18,000
And it's the same for the universe.

297
00:26:18,200 --> 00:26:22,000
Some collision of two dust particles
ten billion years ago

298
00:26:22,200 --> 00:26:26,320
could have led to a chain of
seemingly insignificant,

299
00:26:26,520 --> 00:26:29,040
infinitesimally unlikely
little events

300
00:26:29,240 --> 00:26:33,640
that led to something that we care
deeply about.

301
00:26:33,840 --> 00:26:35,440
Our existence.

302
00:26:41,960 --> 00:26:45,200
Today the way the game of cricket
played out

303
00:26:45,400 --> 00:26:47,040
had an undesired outcome for Bose.

304
00:26:48,680 --> 00:26:51,160
The fielder caught my, er...

305
00:26:51,360 --> 00:26:53,080
caught the ball here.

306
00:26:58,360 --> 00:27:01,320
Had I have hit the ball
a little to the...

307
00:27:01,520 --> 00:27:04,520
to his left or right, it would
have gone to the boundary.

308
00:27:08,040 --> 00:27:11,120
But, sadly, it went straight
to the fielder.

309
00:27:12,400 --> 00:27:14,480
I was like, "Ahh...

310
00:27:14,680 --> 00:27:16,760
"What have I done?"

311
00:27:25,080 --> 00:27:27,080
Just like a game of cricket,

312
00:27:27,280 --> 00:27:30,600
the way the universe played out
to create us humans

313
00:27:30,800 --> 00:27:33,760
was not determined
by the rules alone.

314
00:27:33,860 --> 00:27:37,018
Chance played a part, too.

315
00:27:43,059 --> 00:27:52,343
Bhand Devra Temple
Baran

316
00:28:07,120 --> 00:28:09,520
This temple's over
a thousand years old,

317
00:28:09,720 --> 00:28:12,080
it's dedicated to
Lord Shiva the Destroyer

318
00:28:12,280 --> 00:28:14,440
and it's built
in the Tantric tradition,

319
00:28:14,640 --> 00:28:19,300
which is at least in part
a celebration of pleasure.

320
00:28:19,500 --> 00:28:24,160
But whilst I find some of these
suggestions instructive,

321
00:28:24,360 --> 00:28:25,720
that's not why we're here.

322
00:28:25,920 --> 00:28:28,880
We're here because of the location
of this temple.

323
00:28:35,040 --> 00:28:40,920
Because this temple is in the centre
of a crater, three kilometres wide.

324
00:28:44,040 --> 00:28:46,560
Geologists are still debating
what made it

325
00:28:46,760 --> 00:28:52,000
but it could well be the scar left by
a meteorite smashing into the Earth.

326
00:29:01,680 --> 00:29:07,440
Throughout its lifetime the Earth has been
constantly bombarded by objects from space.

327
00:29:17,400 --> 00:29:19,760
Think about one particular
collision,

328
00:29:19,960 --> 00:29:24,080
the impact that probably wiped out
the dinosaurs 66 million years ago,

329
00:29:24,280 --> 00:29:26,520
and think about the history,

330
00:29:26,720 --> 00:29:30,940
the lifetime of that rock
that smashed into the Earth.

331
00:29:31,140 --> 00:29:35,360
Imagine one particular day
in the lifetime of that rock,

332
00:29:35,560 --> 00:29:39,600
on one orbit, perhaps billions
of years ago,

333
00:29:39,800 --> 00:29:43,400
when another rock,
no bigger than that,

334
00:29:43,600 --> 00:29:46,000
instead of missing it, hit it,

335
00:29:46,200 --> 00:29:50,040
smashed into it and changed
its orbit very, very slightly.

336
00:29:50,240 --> 00:29:57,920
And, over millions and millions of orbits, that change
would have got amplified, until, perhaps, that day,

337
00:29:58,120 --> 00:30:01,640
66 million years ago, instead
of smashing into the Earth,

338
00:30:01,840 --> 00:30:04,560
the dinosaurs were looking up
at the sky

339
00:30:04,760 --> 00:30:07,480
and they saw a fireball
blaze across the sky

340
00:30:07,680 --> 00:30:09,960
and miss rather than hit.

341
00:30:10,160 --> 00:30:11,960
That would have changed history.

342
00:30:12,160 --> 00:30:15,120
In all probability the dinosaurs
would still be roaming

343
00:30:15,320 --> 00:30:20,040
the surface of the Earth today
and we probably wouldn't exist.

344
00:30:28,080 --> 00:30:32,100
But the rock DID strike,
the dinosaurs WERE wiped out,

345
00:30:32,300 --> 00:30:36,320
and purely by chance our human
existence became possible.

346
00:30:42,720 --> 00:30:47,600
And fateful accidents of equal
importance for our existence

347
00:30:47,800 --> 00:30:50,560
have also happened on a much
smaller scale.

348
00:30:55,763 --> 00:31:00,971
Pushkar
Rajasthan

349
00:31:16,720 --> 00:31:19,600
In Pushkar they have quite
a tradition of camel racing.

350
00:31:27,720 --> 00:31:29,160
There's a saying, apparently,

351
00:31:29,360 --> 00:31:32,120
which is the camel
and its driver go their own way...

352
00:31:34,240 --> 00:31:35,880
..and there's the proof.

353
00:31:45,920 --> 00:31:51,200
Despite that, there's a surprising
similarity between camels and us.

354
00:32:01,320 --> 00:32:08,720
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.

355
00:32:08,920 --> 00:32:11,640
What's his name? Rapi. Rapi.

356
00:32:11,840 --> 00:32:13,480
Rapi? Yeah. Right.

357
00:32:13,680 --> 00:32:17,000
So to take my cell sample
is quite easy.

358
00:32:17,200 --> 00:32:18,840
I just have to...

359
00:32:21,080 --> 00:32:23,780
..rub that on the corner
of my cheek

360
00:32:23,980 --> 00:32:26,680
so there are my cheek cells
on there.

361
00:32:28,440 --> 00:32:32,680
I'm going to do the same now
to Rapi, but could you hold him,

362
00:32:32,880 --> 00:32:35,200
hold his mouth open?

363
00:32:42,560 --> 00:32:47,120
Actually, you know what,
can I ask you to come?

364
00:32:47,320 --> 00:32:49,840
There's no way I'm going in there!

365
00:32:50,040 --> 00:32:52,560
Can you just rub that on his cheek?

366
00:32:54,880 --> 00:32:58,380
That...that's going to be
enough, that's plenty.

367
00:32:58,580 --> 00:33:02,080
That's plenty, yeah, and then
hand it over there.

368
00:33:02,280 --> 00:33:03,560
There we go!

369
00:33:05,160 --> 00:33:08,120
Right, thank you, thank you.

370
00:33:10,040 --> 00:33:11,880
I apologise.

371
00:33:12,080 --> 00:33:14,960
So now we've got a...
a sample of Rapi's cells

372
00:33:15,160 --> 00:33:17,220
and a sample of my cells

373
00:33:17,420 --> 00:33:19,480
and we'll make a comparison.

374
00:33:19,680 --> 00:33:20,840
I apologise again.

375
00:33:24,160 --> 00:33:28,800
So this is the slide
of my cheek cell.

376
00:33:29,000 --> 00:33:32,600
You see there it's stained blue.

377
00:33:32,800 --> 00:33:36,660
Quite small, but I can see
detail inside it.

378
00:33:36,860 --> 00:33:40,720
And this is a slide
of the camel's cheek cells.

379
00:33:43,040 --> 00:33:47,280
And the most obvious thing to say
is they look identical,

380
00:33:47,480 --> 00:33:49,160
impossible to tell them apart,

381
00:33:49,360 --> 00:33:53,180
and that's because for all intents
and purposes they are identical

382
00:33:53,380 --> 00:33:57,200
and that's because myself and
the camels over there are mammals.

383
00:33:57,400 --> 00:33:58,240
But...

384
00:33:58,440 --> 00:33:59,960
if you look more closely,

385
00:34:00,160 --> 00:34:03,760
then you see that the cells have
many structures inside them.

386
00:34:05,040 --> 00:34:07,360
The most obvious feature
is the nucleus,

387
00:34:07,560 --> 00:34:09,640
where most of our DNA is stored.

388
00:34:11,400 --> 00:34:14,160
But you can also see
hundreds of little dots.

389
00:34:14,360 --> 00:34:17,120
Many of these structures
are called mitochondria.

390
00:34:21,040 --> 00:34:26,560
These are the power stations
found in the cells
of every complex living thing.

391
00:34:30,360 --> 00:34:34,840
And, yet, once upon a time these
essential structures

392
00:34:35,040 --> 00:34:38,080
were separate,
free-living creatures.

393
00:34:40,480 --> 00:34:44,400
A long time ago,
two or three billion years ago,

394
00:34:44,600 --> 00:34:48,720
the Earth was populated
only by single-celled organisms,

395
00:34:48,920 --> 00:34:53,040
two great kingdoms of life,
the bacteria and the archaea,

396
00:34:53,240 --> 00:34:56,360
and, it has to be said,
things were pretty dull,

397
00:34:56,560 --> 00:35:00,160
there was nothing that we might call
complex and, in fact,

398
00:35:00,360 --> 00:35:02,520
very little happened.

399
00:35:02,720 --> 00:35:07,880
Those two single-celled things just
stayed the same for billions of years.

400
00:35:08,080 --> 00:35:13,840
But then one day, quite by accident,
everything changed.

401
00:35:16,520 --> 00:35:21,240
What many biologists believe to have
happened is that a bacterium

402
00:35:21,440 --> 00:35:26,120
got inside an archaean
and for some reason wasn't digested.

403
00:35:26,320 --> 00:35:29,440
Instead, a symbiotic
relationship began.

404
00:35:31,160 --> 00:35:34,720
The bacterium may have been
protected by the archaean

405
00:35:34,920 --> 00:35:39,600
while the archaean got access to the
energy generated by the bacterium.

406
00:35:47,120 --> 00:35:51,640
Once that cell had access to
the vast amounts of energy,

407
00:35:51,840 --> 00:35:56,000
the potential that the
internal bacterium gave it,

408
00:35:56,200 --> 00:35:58,720
then basically all hell broke loose.

409
00:36:03,760 --> 00:36:08,600
And that energy allowed the cell to
begin to work in larger colonies,

410
00:36:08,800 --> 00:36:11,600
to begin to build complex
living things.

411
00:36:15,880 --> 00:36:20,240
So the mitochondria in your cells
today are the descendants

412
00:36:20,440 --> 00:36:25,448
of that chance collision
billions of years ago.

413
00:36:28,640 --> 00:36:32,040
That singular event,
that fateful encounter,

414
00:36:32,240 --> 00:36:36,840
was purely accidental, but the cells
that it produced had such

415
00:36:37,040 --> 00:36:39,920
a survival advantage,
the energy made available to them

416
00:36:40,120 --> 00:36:51,280
by the mitochondria, that its effect
was amplified beyond imagination
by natural selection, which is not
accidental and it is non-random.

417
00:36:51,480 --> 00:36:55,960
So it's the interaction
between accident and rules,

418
00:36:56,160 --> 00:36:59,440
chance heavily constrained
in the framework of natural laws,

419
00:36:59,640 --> 00:37:04,280
that led to the evolution
of humans here on the Earth.

420
00:37:12,240 --> 00:37:16,280
In our universe there was
no particular aim,

421
00:37:16,480 --> 00:37:19,200
no intention for us humans to exist.

422
00:37:21,640 --> 00:37:26,040
Instead the life of the universe
is just like a game of cricket...

423
00:37:28,880 --> 00:37:32,320
..where rules
and chance play out together...

424
00:37:44,200 --> 00:37:50,240
..and quite by accident happen to
produce a human universe.

425
00:38:09,560 --> 00:38:12,480
Over the course of centuries
we've worked to find

426
00:38:12,680 --> 00:38:18,757
the combination of rules and
accidents that made today's world.

427
00:38:19,800 --> 00:38:22,440
We now understand the laws of nature
so well

428
00:38:22,640 --> 00:38:26,680
that we have at least a reasonable
scientific understanding

429
00:38:26,880 --> 00:38:35,280
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,

430
00:38:35,480 --> 00:38:38,680
it's the great achievement
of modern science.

431
00:38:38,880 --> 00:38:41,880
But just as the origin of the
gods themselves is

432
00:38:42,080 --> 00:38:46,560
questioned in the ancient
Hindu hymns and the Rigveda then

433
00:38:46,760 --> 00:38:51,240
so we are faced with a question,
a very profound question -

434
00:38:51,440 --> 00:38:53,320
who wrote the rules of the game,

435
00:38:53,520 --> 00:38:56,480
what is the origin of
the laws of nature?

436
00:39:03,680 --> 00:39:06,200
What is the origin
of the universe itself?

437
00:39:10,120 --> 00:39:12,240
What went before the Big Bang?

438
00:39:21,760 --> 00:39:28,395
It's a question that takes us
to another world entirely.

439
00:39:40,125 --> 00:39:45,193
Kyoto
Japan

440
00:39:48,400 --> 00:39:52,120
A samurai sword is both sharp
and strong.

441
00:40:04,520 --> 00:40:06,880
Able to cut a body in half...

442
00:40:13,760 --> 00:40:18,799
..but precise enough to slice
through a single hair.

443
00:40:31,480 --> 00:40:35,160
Gassan Sadatoshi is
a master sword maker.

444
00:40:35,360 --> 00:40:39,080
His family have been making swords
for over 800 years.

445
00:40:40,565 --> 00:40:44,745
The Japanese sword is totally unique

446
00:40:44,945 --> 00:40:48,853
it's often said to be the symbol of
Japanese mentality

447
00:40:51,480 --> 00:40:55,880
The first stage is to reduce the
carbon content of the raw material.

448
00:40:56,080 --> 00:40:58,360
If there's too little carbon
it'll be soft,

449
00:40:58,560 --> 00:41:01,280
but too much and it'll be brittle.

450
00:41:18,120 --> 00:41:21,080
This is all a remarkably
high-precision process,

451
00:41:21,280 --> 00:41:25,440
everything that they're doing
matters to make the perfect sword.

452
00:41:28,280 --> 00:41:32,040
And even the force
with which they hammer down matters,

453
00:41:32,240 --> 00:41:36,000
that helps set the precise
mixture of ingredients,

454
00:41:36,200 --> 00:41:42,440
and they're aiming for precisely
0.7% carbon in that steel.

455
00:41:49,240 --> 00:41:53,920
Repeated heating and layering mixes
the iron and carbon

456
00:41:54,120 --> 00:41:56,080
so the block is uniform.

457
00:41:59,200 --> 00:42:03,169
This process can take weeks.

458
00:42:05,440 --> 00:42:09,760
The final stage is to harden
the cutting edge of the sword,

459
00:42:09,960 --> 00:42:13,654
a process called quenching.

460
00:42:15,551 --> 00:42:20,625
Quenching is the most
nerve wracking (part) for a swordsmith

461
00:42:20,825 --> 00:42:25,304
as he has to put his soul into the metal

462
00:42:40,400 --> 00:42:44,200
In the case of a Japanese sword, if
you get all the ingredients right,

463
00:42:44,400 --> 00:42:47,040
the precise mixture
of iron and carbon,

464
00:42:47,240 --> 00:42:51,180
if you get the temperature right,
you get the hammering right,

465
00:42:51,380 --> 00:42:55,190
everything right, over a year,
then you get the perfect sword.

466
00:42:55,390 --> 00:43:03,480
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,

467
00:43:03,680 --> 00:43:12,000
they're called constants of nature, they're things like the strength
of gravity, the speed of light and the masses of the particles.

468
00:43:12,200 --> 00:43:15,360
And they also require precision.

469
00:43:15,560 --> 00:43:18,780
They have to be set in just
the right way

470
00:43:18,980 --> 00:43:24,727
if you want a universe
that supports life.

471
00:43:26,000 --> 00:43:29,080
In the same way that
a samurai sword would be weakened

472
00:43:29,280 --> 00:43:33,520
if the ingredients were different,
the universe might be unable

473
00:43:33,720 --> 00:43:37,960
to support life if the constants
of nature were somehow altered.

474
00:43:42,720 --> 00:43:46,260
Now, if I was some all-powerful
deity, which arguably I'm not,

475
00:43:46,460 --> 00:43:51,120
then I could imagine varying
all those constants of nature
to see what happened.

476
00:43:51,320 --> 00:43:55,200
I could imagine some great big control
board with little knobs on it.

477
00:43:55,400 --> 00:43:59,480
One of them changes the strength
of gravity, the next one changes

478
00:43:59,680 --> 00:44:03,760
the mass of the electron, the next
one changes the speed of light.

479
00:44:03,960 --> 00:44:07,680
And the question is how much freedom do
I have if I want living things to exist?

480
00:44:21,720 --> 00:44:25,560
The answer is, not very much
freedom at all.

481
00:44:27,800 --> 00:44:32,560
If at the Big Bang the strength
of gravity were increased

482
00:44:32,760 --> 00:44:35,800
then the universe would have
collapsed in on itself

483
00:44:36,000 --> 00:44:37,800
before life had time to evolve.

484
00:44:40,800 --> 00:44:46,040
But if the strength of gravity were
decreased then galaxies

485
00:44:46,240 --> 00:44:53,787
wouldn't form, so there'd be
no planets, no stars and no life.

486
00:44:54,800 --> 00:44:58,560
If you decrease the speed of light
by just a few percent

487
00:44:58,760 --> 00:45:01,600
our universe would have
no carbon in it.

488
00:45:04,040 --> 00:45:06,580
Increase it by about the same amount

489
00:45:06,780 --> 00:45:09,320
and our universe would have
no oxygen.

490
00:45:15,600 --> 00:45:20,240
Because we have no idea why the
constants are the values that they are

491
00:45:20,440 --> 00:45:24,720
then we're presented with something of a
mystery, because you can ask the question,

492
00:45:24,920 --> 00:45:29,780
well, if it's just random, if indeed
the universe began and somehow

493
00:45:29,980 --> 00:45:34,210
these random numbers got chosen,
then how lucky are we that we exist?

494
00:45:34,410 --> 00:45:38,640
How lucky are we that we live in a
universe where those constants

495
00:45:38,840 --> 00:45:42,180
are just right to allow
galaxies to from and stars to shine

496
00:45:42,380 --> 00:45:45,720
and elements like carbon to form
in the hearts of stars?

497
00:45:47,040 --> 00:45:52,341
So what could account for the uncanny
precision of this set of numbers?

498
00:46:10,120 --> 00:46:14,320
Hello, can I have just one? Yeah.

499
00:46:19,560 --> 00:46:20,720
Thank you.

500
00:46:21,960 --> 00:46:26,640
You know, our universe, with
all its beautiful laws of nature

501
00:46:26,840 --> 00:46:29,800
and its finely tuned constants,
feels incredibly lucky.

502
00:46:30,000 --> 00:46:33,360
I mean, it's like buying a lottery
ticket and winning the lottery,

503
00:46:33,560 --> 00:46:36,680
but it's stranger than that,
because it's like winning

504
00:46:36,880 --> 00:46:40,000
the lottery in which only one ticket
was ever printed.

505
00:46:43,480 --> 00:46:46,000
But that's of course not how
a lottery works.

506
00:46:46,200 --> 00:46:49,680
Yes, it is extremely unlikely that
I'll win the lottery

507
00:46:49,880 --> 00:46:53,360
with this ticket, but there
are millions of tickets printed

508
00:46:53,560 --> 00:46:56,680
so it's not surprising at all
that someone wins it.

509
00:47:28,680 --> 00:47:33,440
So could we think of our universe
in the same way as the lottery?

510
00:47:33,640 --> 00:47:36,800
The reason that we appear to
live in a perfect universe with

511
00:47:37,000 --> 00:47:39,480
the perfect numbers,
the perfect constants of nature,

512
00:47:39,680 --> 00:47:44,720
the perfect laws, is because there
are in fact countless millions,

513
00:47:44,920 --> 00:47:48,860
perhaps an infinite number
of universes, each with different

514
00:47:49,060 --> 00:47:52,550
physical laws, different numbers,
different constants of nature.

515
00:47:52,750 --> 00:47:55,895
Then we shouldn't be so surprised to
live in the perfect universe.

516
00:47:56,095 --> 00:47:59,240
It's like the lottery - somebody's
got to get the right ticket,

517
00:47:59,440 --> 00:48:00,960
somebody's got to win it.

518
00:48:06,240 --> 00:48:08,760
Just as the lottery has many
tickets,

519
00:48:08,960 --> 00:48:11,603
each bearing different numbers...

520
00:48:13,040 --> 00:48:15,400
..so there may be many universes,

521
00:48:15,600 --> 00:48:19,880
each with different values for
the constants of nature.

522
00:48:23,360 --> 00:48:27,000
Universes with stronger or weaker
gravity,

523
00:48:27,200 --> 00:48:29,520
slower light or faster light.

524
00:48:32,920 --> 00:48:35,680
Now, that might make sense
mathematically

525
00:48:35,880 --> 00:48:38,640
but is it really
a sensible suggestion,

526
00:48:38,840 --> 00:48:41,100
an infinite number of universes?

527
00:48:41,300 --> 00:48:43,560
What does that mean for reality?

528
00:49:06,079 --> 00:49:11,754
Miyake Jima island.
North Pacific

529
00:49:14,360 --> 00:49:21,360
3,000 people live here,
making a living from the sea.

530
00:49:32,480 --> 00:49:36,993
But it's a precarious
place to call home.

531
00:49:44,680 --> 00:49:48,280
Because this entire island is
an active volcano.

532
00:50:04,560 --> 00:50:07,840
Occasionally it belches forth
scorching lava that

533
00:50:08,040 --> 00:50:10,600
incinerates anything that
stands in its way.

534
00:50:15,400 --> 00:50:20,240
Until an eruption in 1983,
this was the island's school.

535
00:50:27,120 --> 00:50:33,884
But volcanism doesn't just destroy,
it also creates.

536
00:50:39,120 --> 00:50:43,260
Around 30,000 years ago this
whole island emerged

537
00:50:43,460 --> 00:50:47,600
from the vast emptiness of
the North Pacific Ocean.

538
00:50:51,480 --> 00:50:59,360
And it's not just this island, it's
the whole of the Izu Archipelago
and much of Japan.

539
00:50:59,560 --> 00:51:06,080
All of these islands have risen up
out of the ocean,
seemingly from nothing.

540
00:51:12,800 --> 00:51:16,148
And it's even happening right now.

541
00:51:21,320 --> 00:51:29,400
This island, called Nishinoshima,
has been growing steadily
since it suddenly
appeared in November 2013.

542
00:51:37,040 --> 00:51:40,320
If we didn't know better, we might
ascribe that creation

543
00:51:40,520 --> 00:51:42,600
to the act of the gods,
but we do know better

544
00:51:42,800 --> 00:51:46,220
because we know about geology,
we've done some science,

545
00:51:46,420 --> 00:51:49,640
so we know that the origin of
this island is volcanism.

546
00:51:49,840 --> 00:51:53,640
It comes from the inner heat of the
Earth, which is itself a leftover

547
00:51:53,840 --> 00:51:57,840
from the history of its formation
4½ billion years ago.

548
00:51:58,040 --> 00:52:02,040
So we have a mechanism
for the creation of new land.

549
00:52:05,480 --> 00:52:08,560
Contrast that with the scientific
explanation for the origin

550
00:52:08,760 --> 00:52:12,960
of the most important thing of all,
the origin of the universe itself,

551
00:52:13,160 --> 00:52:15,440
and for decades
we've been happy to say

552
00:52:15,640 --> 00:52:17,480
the universe began at the Big Bang

553
00:52:17,680 --> 00:52:21,400
and it's almost as if we're
not to ask what happened before.

554
00:52:21,600 --> 00:52:22,600
There was nothing before,

555
00:52:22,800 --> 00:52:27,440
there's no scientific mechanism to
explain how the Big Bang occurred.

556
00:52:30,440 --> 00:52:33,880
But there are now plausible
theories that provide

557
00:52:34,080 --> 00:52:38,680
a mechanism for how universes might
be made from apparently nothing.

558
00:52:44,160 --> 00:52:49,960
So what is this magical
theory that explains
the origin of the universe,
and how did we find it?

559
00:52:50,160 --> 00:52:53,240
Well, the answer is it's a theory
called inflation,

560
00:52:53,440 --> 00:52:57,240
and really the clues
to the theory were there all along,

561
00:52:57,440 --> 00:52:58,840
we just had to look for it.

562
00:52:59,040 --> 00:53:01,640
They lie in the rules of the game.

563
00:53:02,920 --> 00:53:07,720
If there's one basic rule
it's this - things have to happen.

564
00:53:07,920 --> 00:53:11,000
Nothing, emptiness,
is about the only thing that's

565
00:53:11,200 --> 00:53:14,040
forbidden by the rules of
quantum mechanics.

566
00:53:21,160 --> 00:53:29,560
Before our universe
became filled with
particles of matter, it wasn't
empty, it was filled with energy,

567
00:53:29,760 --> 00:53:35,460
and like the surface of the sea it
was constantly fluctuating, rippling

568
00:53:35,660 --> 00:53:43,419
with a form of energy that causes
space to expand exponentially fast.

569
00:53:45,560 --> 00:53:48,920
At the trough of one of the waves,
the energy driving

570
00:53:49,120 --> 00:53:51,480
the expansion
fell below a certain level.

571
00:53:54,960 --> 00:53:59,520
So that region stopped inflating and
the energy was transformed

572
00:53:59,720 --> 00:54:05,053
into the recognisable particles
of today's universe.

573
00:54:06,000 --> 00:54:09,920
And that transformation is what we
see as the Big Bang,

574
00:54:10,120 --> 00:54:12,760
the birth of
our observable universe.

575
00:54:15,600 --> 00:54:18,160
The theory of inflation
is extraordinary

576
00:54:18,360 --> 00:54:22,400
and extraordinary claims
require extraordinary evidence.

577
00:54:22,600 --> 00:54:25,920
Well, here is
the extraordinary evidence.

578
00:54:26,120 --> 00:54:30,140
This is a photograph of
the oldest light in the universe

579
00:54:30,340 --> 00:54:34,160
and it's got many intricate
and detailed properties.

580
00:54:34,360 --> 00:54:39,080
The most obvious one is that
it's an extremely uniform glow,

581
00:54:39,280 --> 00:54:41,560
it's almost all at the same
temperature.

582
00:54:43,160 --> 00:54:46,940
This and all the other properties
of this ancient light are best

583
00:54:47,140 --> 00:54:50,920
explained by an inflationary
expansion of the early universe.

584
00:54:52,880 --> 00:54:59,402
No-one has thought of any theory that
can reproduce this other than inflation,

585
00:54:59,602 --> 00:55:02,600
and that is why I love physics.

586
00:55:02,800 --> 00:55:04,640
Isn't that remarkable?

587
00:55:11,200 --> 00:55:14,200
But, just like the formation
of islands or any other

588
00:55:14,400 --> 00:55:19,760
mechanism in nature, inflation
needn't stop at one universe.

589
00:55:21,360 --> 00:55:23,160
Why should it?

590
00:55:29,800 --> 00:55:33,920
The process of inflation could be
going on eternally,

591
00:55:34,120 --> 00:55:37,120
always making universes, even now.

592
00:55:41,760 --> 00:55:43,440
And each one of these universes

593
00:55:43,640 --> 00:55:46,240
could be like a ticket
in a lottery...

594
00:55:50,760 --> 00:55:54,560
..bearing different numbers for
constants of nature...

595
00:55:56,120 --> 00:56:00,080
..such as the strength of gravity
or the speed of light.

596
00:56:07,560 --> 00:56:09,880
So amongst them all...

597
00:56:10,080 --> 00:56:12,320
there has to be a winning ticket.

598
00:56:15,960 --> 00:56:17,760
A human universe.

599
00:56:22,520 --> 00:56:24,520
It's absolutely inevitable.

600
00:56:36,720 --> 00:56:40,500
If the theory of inflation is
correct, it explains

601
00:56:40,700 --> 00:56:44,480
how our universe appeared
apparently from nothing.

602
00:56:46,800 --> 00:56:51,680
And it also strongly suggests that
there's not just our universe

603
00:56:51,880 --> 00:56:55,840
but a vast number,
perhaps even an infinity of them.

604
00:57:24,560 --> 00:57:28,440
Now we've known for a long time
that we're infinitesimal specks

605
00:57:28,640 --> 00:57:32,960
in a vast universe,
but now the suggestion is that

606
00:57:33,160 --> 00:57:38,240
we're infinitesimal specks
in a vast infinity of universes.

607
00:57:41,600 --> 00:57:45,120
Our current best theory for
the origin of the universe,

608
00:57:45,320 --> 00:57:49,520
backed up by experimental evidence,
suggests that there are an infinite

609
00:57:49,720 --> 00:57:54,120
number of universes, an infinite
number of copies of you and me,

610
00:57:54,320 --> 00:57:59,680
and that the existence of the
whole thing is inevitable.

611
00:57:59,880 --> 00:58:05,240
No purpose, nothing special,
you are because you have to be.

612
00:58:05,440 --> 00:58:07,280
How does that make you feel?

613
00:58:07,480 --> 00:58:11,720
Well, the wonderful
thing is nobody knows,

614
00:58:11,920 --> 00:58:16,840
nobody's worked it out yet,
so the answer is up to you.

615
00:58:18,080 --> 00:58:19,440
What do you think?

616
00:58:29,330 --> 00:58:33,774
For small creatures such as we,

617
00:58:34,251 --> 00:58:38,235
For small creatures such as we,
the vastness is bearable only through love

618
00:58:38,435 --> 00:58:42,983
For small creatures such as we, the vastness
is bearable only through love Carl Sagan

619
00:58:46,055 --> 00:58:53,007
End