we are made from very small things and

we live in a very very big universe and

the small things are so small and the

big things are so big that you might

think we have no hope of ever

understanding them but I'm going to

argue that in fact we already understand

them quite well it's the world in

between the big and the small the world

we live in that we don't understand and

in fact that world is becoming harder

and harder to understand because we keep

discovering more complexity and creating

more complexity and that's something we

have to face if we want to solve our

biggest challenges but let's start in

the beginning I want to tell you how we

came to understand the big that's my

background I studied physics and

cosmology and it also has to do with

where I grew up I grew up in a town

called Olivia's got in Finland where you

get about four hours of daylight during

the day so whenever I walked home from

school it would be dark and I would look

at the stars and it's the stars that

really tell you how big the universe is

stars are very big as bigger bigger as

our Sun only very very far away and

there are so many of them even with the

now ten thousand is a big number but

it's still a comprehensible number if

each star was a grain of sand ten

thousand would be about three teaspoons

of sand so that's not so bad but of

course we don't look at the stars with

the naked eye anymore we use telescopes

and already a hundred years ago around

1900 astronomers had good telescopes and

they could see over a million stars now

a million stars is a lot but it's still

a comprehensible number it's about a

bucket of sand and in fact those

astronomers were pretty sure that that

was it that there were about a million

stars in the universe except for these

funny smudges they had seen in their

photographs and they called them spiral

nebulae and nobody knew what those we're

and it took

a computer to figure out what those

actually we're a human computer called

Henriette believe it because back then a

computer was what you called a woman

doing calculations for scientists now

leave it was paid ten dollars a week to

analyze photographs of stars and she was

deaf but she had a very very good eye

brightness of stars that gave her a new

way to actually figure out how far away

stars we're and he died of cancer very

young but I was able to publish her

finding but couldn't see it applied and

it was Edwin Hubble who later said that

leave it should have really won the

Nobel Prize who used her method to look

at those spiral nebulae and what he

found was that they were much much much

further away millions of times further

away than anyone had ever thought in

fact they were galaxies galaxies just

like our Milky Way systems of hundreds

of billions of stars

and we now know that the visible

universe has hundreds of billions of

galaxies so it's not just a bucket of

sand it's not a million stars it's seven

times 10 to the power of 22 stars now

again if each star was a grain of sand

that would be all the sand in all the

desert sand beaches and sand boxes on

earth times ten thousand ten thousand

wells of sand so in less than a hundred

years that's how much our understanding

of the universe has grown from three

teaspoons to ten thousand Wells of sand

and actually it's even worse because

getting bigger and bigger all those

galaxies are moving away from each other

at tremendous speed so you may wonder

how could we ever figure out what was

going on and what what what where all

those stars came from now fortunately

Einstein came along and Einstein came up

with a theory of relativity that says

that space is really just distances

between points and those distances

change depending on what you have

between those points he came up with

equations that tell us how space itself

changes when matter and energy move

around in it and his equations work

extremely well so well that's all the

phones

in your phones use GPS which is based on

Einstein's equations an Einstein's

equations predicted an expanding

universe and at first we thought he'd

made a mistake but then he found out

about Hubble's discovery and we now know

that the universe has been expanding for

13.8 billion years that means it

actually started out very very small

smaller than an atom and we call the

moment the expansion started the Big

what happened at the very instant of the

Big Bang but thanks to Einstein we do

know how the universe got to be so big

and we know that little ripples tiny

little ripples in that early universe

grew with the universe into seeds that

became stars and galaxies so we do know

where stars came from now one of

Einstein's equations had really big

implications not just for big things but

also for small things and that's his

most famous equation Z equals MC squared

what does it mean well e means energy M

is mass and C squared is speed of light

squared light travels very very fast so

C squared is an enormous number almost

as big as the number of all the grains

of sand in the world and that means that

even the tiniest amount of matter even

an atom has a tremendous amount of

energy so let's talk about atoms and

let's talk about small things how small

are atoms now if you remember that

tremendous number of stars in the

universe we have the same number of

atoms in just three drops of water so

it's quite amazing that we can

understand in all and for a long time we

thought atoms where the smallest thing

discovered an element called

radium and radium was constantly

radiating so much energy that it

couldn't possibly come from reactions

between atoms and people could really

excited about radium science fiction

writer HT wells thought that it could be

a source of infinite power for a utopian

society some people got maybe a little

bit too excited and too carried away and

started putting radium in products like

chocolate and face cream and and other

things something we now know wouldn't

would it be a good idea now Mary Curie I

did something a bit better she was able

to use radium to treat cancer so if he

pioneered radiation therapy but she

herself got exposed

so much radiation that she eventually

died of anemia and even her cookbook to

this day is harmful radioactive but he

lived long enough to see what was really

going on with radium and she suspected

that there might be something going on

inside atoms something that was

converting matter into energy like

Einsteins equation implied and he was

right in 1911
Ernest Rutherford took some radium fired

some of radium's radiation at a gold

leaf very thin gold leaf and saw

something really weird the atoms were

behaving like there was something much

smaller inside something compared to the

size of the atom like a grain of sand in

the middle of a football field and he

had discovered the nucleus the nucleus

of an atom is made out of particles

called protons and neutrons orbited by a

cloud of electrons and to explain his

structure of the atom scientists had to

come up with a new theory called quantum

mechanics and quantum mechanics predicts

that if you split the atom if you split

the nucleus some matter will be

converted into energy and that's what

was going on with radium but Rutherford

himself didn't think that atomic energy

would be of any practical use he

famously said that anyone who looks for

a soft source of power inside an atom is

talking absolute moonshine so of course

there was a very stubborn Hungarian who

decided that it had to be made to work

and he was called Leo Szilard and he was

born right here in Budapest

as a young man he did a lot of work with

Einstein and they became close friends

thermodynamics theoretical physics and

they also invented a new type of fridge

old-fashioned fridges used very

poisonous gases and a family in Berlin

died of Hume scumming coming from those

gases an Einstein got really upset about

it and he was certain that they had beer

had to be a better way to build fridges

so he asked sea lard for help - to

invent a better one so they did it was a

genius design obviously but too

expensive and too noisy to be actually

practical but in the end they made some

money by selling their patents to

Electrolux but sea lard kept inventing

and his next invention was something

much much bigger

in 1933 one morning in London he was

crossing the street at this spot and

just the moment when the traffic light

changed in a flash he had a really

beautiful and a really terrible idea

and he called it the chain reaction if

you could split just one atom that would

release neutrons that would split more

atoms that release more neutrons that

would split more atoms and so on and so

on you could make atomic power work and

weapon and that's exactly what happened

in hiroshima and nagasaki 12 years later

and szilárd himself was horrified he

spent the rest of his life campaigning

against nuclear weapons and he switched

fields from physics to biology and the

atomic bomb is a terrible thing it shows

that there is a dark side to our

understanding of the big in the small

but actually that same understanding

triggered an even bigger explosion

that's still going on today and the

trigger for that explosion was this this

is the first transistor it's a device

about this big it was built by a team

led by William Shockley in Bell Labs in

1947 and what it is is the simplest

building block of a digital computer it

can store a 0 or a 1 and like the atomic

bomb it's based on quantum mechanics in

fact on equations worked out by another

hand garyun called Eugene Wigner who is

one of szilard's friends as well and we

can I showed that there are some

materials that can be made to sometimes

conduct electricity and sometimes not so

that gives you the 1 and 0 and one of

those materials is silicon and silicon

is basically sand so we make transistors

very very very good at it here's a

modern transistor it's about 20

nanometers in size and to give you an

idea how small that is

all the 2 billion transistors in an

iPhone 6 can be made from just two

grains of sand so in 1947 there was just

one transistor today there are 3 times

10 to the power of 21 transistors

that's thousand times all the sand

grains in the world and in just in ten

years there will be more transistors

than there are stars in the known

universe

so we really have started another big

band now think about that for a minute

that's a number that applies not to

atoms but machines that we have made

what does it mean it means we can see

things that we could never see before

the Henry at the levites of today don't

have to do it all by hand computers are

storing data and analyzing it for us and

just like telescope

revealed a much much much bigger

universe computers are revealing a world

that is much more complex than we

thought and that world is around us and

this is a human skin cell so it looks

pretty complicated but thanks to

computers we can now read the code that

runs it we can read its DNA for a long

time scientists thought that only about

2% of that DNA did anything useful and

the rest was junk but recently we got

much better at reading DNA and now we

know that that 98% is actually the

control system for the cell so in just a

few years we found out that the cell is

actually at least 50 times more complex

than we thought now to give you an idea

of what how big a leaf that is let's

think about in terms of computer

programs a small iPhone app like like

candy crush is about 50,000 lines of

code so what 50 times more code give you

it would give you the control system for

CERN's Large Hadron Collider the most

complicated science instrument in the

world so basically we thought a cell was

like candy crush but it turns out to be

more like the Large Hadron Collider in

terms of complexity so that means it's

much harder to fix if something goes

wrong so it's no wonder that we are

really far still from curing cancer and

maybe that's because we've been looking

to fix that we really need to tackle the

cells full complexity it's not just that

we are just using transistors to

discover complexity we're using them to

build complexity we're putting them in

every single device we build and connect

them all together now look at the

Internet in 1977 and then look at it in

2007 it's like a chain reaction the more

complex things we built the more complex

things they allow us to build and now

our transport networks our financial

systems our energy systems are much much

more complex than ever before and

there's a problem with that because very

complex systems can become fragile and

adding a single grain of sand to a sand

pile can trigger an avalanche and those

avalanches are happening faster and

faster we're all familiar with 2008

financial crisis but in 2010 competing

trading algorithms got locked into a

feedback loop that created a trillion

dollar stock market crash in 45 seconds

what's called the flash crash of 2:45

p.m.

connections also mean that problems

spread very very quickly three billion

that the next pandemic we're going to

have is going to be truly global in a

very complex system you can also get

cascading failures one thing failing off

to another this is the electricity grid

of India and in 2012 just one power line

being overloaded crash the entire grid

left 600 million people without power

for three days and sometimes connections

can be very very hard to see

imagine a forest fire in Russia what

does that have to do with the Arab

Spring

well forest fires in Russia led to the

grain export ban which caused massive

financial speculation on food prices

which caused feud riots in North Africa

and ultimately to people deciding they

finally had enough our most difficult

problems like climate change involve

both the complexity of nature and the

complexity we regret creating to fix

climate change we need to understand

finance we need to understand energy we

need to understand soil and biology and

the atmosphere and and the oceans and

quantum mechanics carbon and light all

of those things at the same time so we

live in a world where most of what we

breaking means that big things break and

when things break they break very

quickly everything is connected and we

can't see those connections and to

understand anything you have to

understand everything so that's a little

bit scary but there's no reason to panic

it's actually also quite exciting from

for me looking at all these complexities

to like looking at those stars again and

that's why I did what CLR did and

switched from physics to biology there

are amazing new opportunities if we can

learn to live with complexity and I

think we can actually we now have the

means to make a lot of things much

simpler a lot of our systems like

finance and energy are fragile because

they have central nodes like banks and

power plants that are connected to

everything else so what if we took those

away think about technologies like solar

power or Tesla's power wall again both

powered by transistors maybe we can have

power systems that are much less

centralized and much more resilient we

might be able to do the same thing for

finance Bitcoin is an example of a

transactions without a central authority

like a bank that verifies them but what

about the complexity of nature now

cancer and climate change are soda

problems that they might be too much

even for an Einstein but what about a

million Einsteins

all working together where could we find

those Einsteins well the chances are

that a lot of those Einsteins are now

playing computer games and just all the

hours spent on playing Angry Birds

actually would translate into twelve

Wikipedia's every year and actually the

best way to find a shape of a biological

molecule is already a computer game

called Foldit with 15 million players

there are other platforms like that like

Zooniverse that mean that anyone can now

try to find cancer mutations or new

kinds of galaxies in huge sets of data

and we might even be able to apply that

approach to politics iceland recently

tried to crowdsource the drafting of the

Constitution by social media and now you

might think that was a terrible idea but

actually worked out quite well so there

there are ways to make democracy more

transparent and have more brains working

could ever understand it may be that we

have to give up some ideas about systems

that we have like the fact that we may

not need to be able to understand the

nature of all systems without

understanding them that my company heals

Nano we're trying to build molecular

machines that make writing genetic code

easier using machines that we've evolved

in a test tube and not designed so in a

way we can tackle complexity by

accepting it and embracing it and maybe

ultimately the systems we build will

merge with the systems of nature until

we can no longer tell where one ends and

one begins

Einstein said that things should be as

simple as possible but no simpler and

that's a good rule for us to follow both

as a species and in our lives so let's

embrace complexity where we must but

find simplicity where we can and this is

thought I'd like to leave you with

there's a name for the time in our lives

where everything we think we know turns

out to be wrong where everything is too

complex everything is too overwhelming

and we don't know what to do and it's

adventures really begin thank you very

much