The Secret Life of Chaos Page #3

abstract science.

The way Belousov's chemicals

move as co-ordinated waves

is exactly the way our heart

cells are co-ordinated as they beat.

Animal skins and heart beats.

Self-organisation seems to operate

all over the natural world.

So why were the scientific community

in Turing and Belousov's day,

so uninterested, or even hostile to

this astonishing and beautiful idea?

Well, the reason was all too human.

Mainstream scientists

simply didn't like it.

To them it seemed

to run counter to science,

and all that it had achieved.

To change that view

would require a truly shocking

and completely unexpected

discovery.

In essence, by the beginning

of the 20th century,

scientists saw the universe

as a giant,

complicated, mechanical device.

Kind of a super-sized

version of this orrery.

The idea was that the universe

is a huge and intricate machine

that obeys

orderly mathematical rules.

If you knew the rules of how the

machine was configured to start with,

as you turned the handle,

over and over again,

it would behave

in an entirely predictable way.

Back in the times of Isaac Newton

when people were discovering

the laws that drove the universe,

they came up with this kind of

metaphor of a clockwork universe.

The universe looked like a machine

which had been set going at the

instant of creation and just

followed the rules and ticked along.

And it was a complicated machine and

therefore complicated things happen.

But once you set it going

it would only do one thing,

and the message

that people drew from this

was that anything describable

by mathematical rules

must actually

basically be fairly simple.

Find the mathematics

that describes a system

and you can then predict

how that system will unfold.

That was the big idea.

It began with Newton's

law of gravity

which can be used to predict

how a planet moves around the sun.

Scientists soon found many

other equations just like it.

Newtonian physics seemed

like the ultimate crystal-ball.

It held up

the tantalising possibility

that the future could,

in principle, be known.

The more careful

your measurements are today,

the better you can predict

what will happen tomorrow.

But Newtonianism

had a dangerous consequence.

If a nice mathematical system,

that worked in a similar way

to my orrery, did sometimes become

unpredictable, scientists assumed

some malign outside force was

causing it. Perhaps dirt had got in?

Perhaps the cogs were wearing out?

Or perhaps someone

had tampered with it?

Basically we used to think,

if you saw very irregular behaviour

in some problem you're working on,

this must be the result of some sort

of random outside influences,

it couldn't be internally generated.

It wasn't an intrinsic part

of the problem,

it was some other thing

impacting on it.

Looked at from this point of view,

the whole idea of self-organisation

seemed absurd.

The idea that patterns of the kind

Turing and Belousov had found

could appear of their own accord,

without any outside influence,

was a complete taboo.

The only way for self-organisation

to be accepted

was for the domineering

Newtonian view to collapse.

But that seemed very unlikely.

After all, by the late '60s

it had delivered

all the wonders of the modern age.

Beautiful, beautiful.

Ain't that something?

Magnificent desolation.

But then, at the same time

as the moon mission,

a small group of scientists,

all ardent Newtonians,

quite unexpectedly

found something wasn't right.

Not right at all.

During the second half

of the 20th century,

a devil was found in the detail.

A devil that would ultimately

shatter the Newtonian dream

and plunge us literally into chaos.

Ironically, the events that forced

scientists to take self-organisation

seriously was the discovery

of a phenomenon known as chaos.

Chaos is one of the most over-used

words in English, but in science

it has a very specific meaning. It

says that a system that is completely

described by mathematical

equations is more than capable

of being unpredictable without

any outside interference whatsoever.

There's a widespread misapprehension

that chaos is just somehow saying,

the very familiar fact,

that everything's complicated.

I mean, the nitwit chaoticist

in Jurassic Park,

was under that confusion.

It's something much simpler and

yet much more complicated than that.

It says, some very, very simple

rules or equations,

with nothing random in them,

they're completely determined,

we know everything about the rule,

can have outcomes

that are entirely unpredictable.

Chaos is one of the most

unwelcome discoveries in science.

The man who forced the

scientific community to confront it

was an American meteorologist

called Edward Lorenz.

In the early 1960s he tried

to find mathematical equations

that could help predict the weather.

Like all his contemporaries,

he believed that in principle

the weather system was no

different to my orrery.

A mechanical system

that could be described

and predicted mathematically.

But he was wrong.

When Lorenz wrote down what looked

like perfectly simple mathematical

equations to describe the movement

of air currents,

they didn't do

what they were supposed to.

They made no useful predictions

whatsoever.

It was as if the lightest breath

of wind one day could make the

difference a month later between a

snowstorm and a perfectly sunny day.

How can a simple system that works

in the regular clockwork manner

of my orrery become unpredictable?

It's all down

to how it's configured.

How the gears are connected.

In essence,

under certain circumstances,

the tiniest difference in

the starting positions of the cogs,

differences that are too small

to measure,

can get bigger and bigger

with each turn of the handle.

With each step in the process

the system then moves

further and further away

from where you thought it was going.

Lorenz captured this radical idea in

an influential talk he gave called,

"Does a flap of a butterfly's wings

in Brazil set off a tornado

in Texas?"

It was a powerful

and evocative image

and within months a new

phrase had entered our language.

"The butterfly effect."

And the butterfly effect,

the hallmark of all chaotic systems,

started turning up everywhere.

In the early '70s, a young

Australian called Robert May,

was investigating a mathematical

equation

that modelled how animal

populations changed over time.

But here too lurked

the dreaded butterfly effect.

Immeasurably small changes to the

rates at which the animals reproduced

could sometimes have huge

consequences

on their overall population.

Numbers could go up and down wildly

for no obvious reason.

The idea that a mathematical

equation gave you the power

to predict how a system will behave,

was dead.

In some sense this is

the end of the Newtonian dream.

When I was a graduate student,

the belief was,

as we got more and

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