Quantum physics for seven-year-olds | Dominic Walliman | TEDxEastVan

In this lighthearted talk, Dominic Walliman gives us four guiding principles for easy science communication and unravels the myth that quantum physics is difficult to understand, it's all in how it's explained.

Dominic Walliman is a physicist, and award-winning science writer. He received his PhD in quantum device physics from the University of Birmingham and currently works at D-Wave Systems Inc., a quantum computing company in Vancouver. Dominic grew up reading science books, and remembers vividly the excitement of discovering the mind-boggling explanations that science gives us about the universe. If he can pass on this wonder and enjoyment to the next generation, he will consider it a job well done.

This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at http://ted.com/tedx

So, have you ever had this experience?

You're having a chat with someone

and they're telling you something
about a subject they're very interested in

or they know a lot about,

and you're following along.

Then, at some stage you realize you kind
of lost the thread of what they saying.

And then, you're standing there

and you realize you have absolutely
no idea what they're talking about.

(Laughter)

I had this recently with a friend
who knows a lot about investing.

And it's something I don't know
a huge amount about,

but it's very important,
very useful information.

But he started talking about
kind of diversified investment portfolio -

blah -

(Laughter)

And unfortunately, I went away
with no useful information.

So, I think it's a situation
we all are familiar with,

and fortunately there's things you can do
to improve this situation,

which is what I'm going
to talk about today.

So, I'm a scientist.
I work in the area of quantum physics.

And so, I've been on both sides
of this kind of interaction.

I've both been the guy explaining
very complicated material to someone,

but I've also been on the receiving end

of lots of very kind of intense scientific
discussions with my colleagues.

And, when this kind of breakdown
of communication happens,

I've noticed something interesting,

which is that, as a person
who's stopped understanding,

you feel kind of guilty about it.

But, if you think about it,
this is completely wrong,

it's the wrong way around
because at that point in time,

there's literally nothing you can do
to understand better.

But there is something that the other
person can do to help you understand

by finding a better way of explaining
what they're talking about.

And so -

during my experience in science,

I found that the only way to survive
was to kind of have the courage

to politely stop the person
who is explaining,

say, "I'm sorry, I don't understand
what you're saying,"

and then try and go back and start off
from where I'd lost the thread.

And it does take
a bit of courage to do this

because you're kind of admitting that you
don't know, you know, the subject matter.

But I think that's OK, and in fact,
my fears were completely unwarranted.

Generally people respect you
if you care much about, you know,

knowing the right information

or care about, like,
understanding it properly.

So, I think we should never ever feel bad
about not knowing something

and we should never feel bad
about asking questions.

So, I do a lot of science communication,

and science really has
this communication issue with it

because generally
the subject matter is very complex.

And you might know
scientists are always complaining

about how their research
is being misrepresented by the media,

like "Drinking wine cures cancer."

(Laughter)

It totally doesn't, by the way.

But on the other hand,
you can kind of understand

how journalists will maybe
oversimplify things or get things wrong

because, to explain cutting-edge research,

you kind of need a PhD
in the subject beforehand,

and that's not something we can expect,
you know, the media, journalists to have

in all the different
scientific disciplines.

So, I think the world would be very
well-served by a whole load of people

who are really good
at science communication,

people who understand the science
but can also explain it in a way

that the general public can understand.

And this is important for many reasons,

but one reason is you might know

that just about all the science research
that goes on around the world

is publicly funded.

So, it'd be nice if the general public
could actually understand

the work that their money
is going towards.

But for me, the even more important reason
that science communication is good

is because it's also interesting.

The research going on is so fascinating
it'd be nice if people could access it.

Take my field for example,
quantum physics.

I find quantum physics to be
a deeply interesting subject,

but it's one that gets this reputation
of being incredibly difficult.

And that's fair, it gets complicated
when you get down into the details,

but it doesn't mean
you can't talk about it at all.

So, let me get a show of hands.

So, put your hand up if you don't know
what quantum physics is.

And if you don't, don't feel bad about it.

Raise your hand, you know.
Own your ignorance.

It's totally fine.

Okay, okay, right.

So, quantum physics is the description
of the smallest things in our universe.

So, if you zoom right down
smaller than cells,

down to the scale of molecules, atoms,
and things atoms are made of,

you know, subatomic particles,
protons, neutrons, electrons,

it just describes how they all work
and also how they interact with light.

And the interesting thing
about quantum physics is

it's like the fundamental rules
of the universe,

and yet, the things that happen there
are so very strange.

So, I'll tell you a few of the phenomena
that go on in quantum physics.

One you might have heard of
is called particle wave duality.

So, you can imagine
all these subatomic particles,

these protons, neutrons, electrons,
like little bouncy balls,

kind of bouncing around,
bouncing off each other.

But sometimes you have to treat them
as like spread-out waves.

And they kind of do both at the same time,
which is hard for us to imagine.

So, I'll paint a picture.

Imagine dropping one of these bouncy balls
into like a pond of water.

The ball would disappear,

and then you'd get these ripples
going out over the surface.

Now, imagine one
of the ripples hits, say, a stick.

All of the ripples
on the surface disappear,

and by that stick suddenly
a bouncy ball pops out again.

That's kind of strange
for us to think about, right?

But this is the kind
of behavior that goes on

in the subatomic realm all the time.

Another phenomena you might have heard
is called quantum tunneling.

So, imagine I've thrown one of these
bouncy balls against a window.

So, it would be like bounce - oh, sorry -

throw, bounce, catch -

throw, bounce, catch -

throw -

It's gone completely through the window.

It's not smashed it.
It's not interacted with it at all.

It's just suddenly
on the other side of the window

and you can see it flying away.

(Laughter)

If we saw that,
we'd think it was crazy, right?

But this goes on at the
subatomic realm all the time.

In fact, it's the only reason we exist.

So, you might know that, in the Sun,

the way it generates energy
is through nuclear fusion.

And nuclear fusion is when
two hydrogen atoms come together

and the protons in their nucleus
bounce off each other.

Now, if it wasn't for quantum tunneling,

they'd bounce off each other
and nothing would happen.

But what actually happens is
they quantum-tunnel into each other,

and that's what lets them fuse
and release the sunlight,

and without that sunlight,
we wouldn't exist.

So, we can thank quantum tunneling
for our existence.

Another phenomenon
is called superposition.

And it's a very fancy word,

but all it means it something that can do
opposite things at the same time.

So, for example,

I can spin around one way,

I can spin around the other way,

but what would it look like for me

to spin around in both directions
at the same time?

(Laughter)

We can't do that, we can't imagine that,

but this is what these subatomic
particles do all the time.

And in fact, we can kind of do it,
at least bits of us can.

So, if you've ever been in an MRI machine,

what an MRI machine does is it finds
all the hydrogen atoms in your body

and makes them spin around
in both directions at the same time

in this superposition.

This is what allows us to see
inside of people's bodies.

So, it's interesting that all of this
physics seems so kind of abstract

and remote from our everyday experience.

And yet, it's happening inside our bodies,
we're made of quantum stuff.

So, it's happening everywhere around us.

And it's no just MRI machines
that we use tech like quantum physics for.

There's been a whole host
of other technologies that come about

because of our understanding
of quantum physics.

So, one of those
is our understanding of silicon

allowed us to invent the silicon chip,

which is in every single
computer in the world.

So, the entire computing
infrastructure of the world exists

because of our understanding
of quantum physics.

And it's in other things, like lasers -
they're quite useful -

and nuclear power plants.

And there's this other sound bite you
might have heard about quantum physics:

it's that no one really
understands quantum physics.

Well, that's actually wrong.

We do understand
quantum physics very well,

and you'd kind of hope that we did

if it forms the technology MRI machines
or nuclear power stations.

What they mean when they say that

is that when we try and picture
in our heads something

that can be both a particle
and a wave at the same time,

or something that can spin around
in two directions at the same time,

we find it very hard
to picture that in our heads.

But we can describe it all very well
using mathematics.

So, it's fascinating that something can be
so counterintuitive on one hand,

but yet, can be so practically
useful on the other.

So, I really enjoy explaining
science to people.

I make YouTube videos
and also write kids books

for the age range around seven
to eleven-year-old,

and I really like pushing myself,
I don't hold back on the science,

I like explaining the most
complicated subjects to that age.

So, quantum physics, nanotechnology,
relativity, rocket science,

those kinds of things.

And I've come to the conclusion

that you can pretty much explain
anything to anybody,

as long as you go about it the right way,

and I've come up with a set
of principles I work by to do that.

So, I'm going to share these with you.

So these are my four principles
of good science communication.

And I say science, but it can be
any kind of technical communication.

Okay.

So, number one:

start off in the right place.

So, everyone's got a different background,

everyone's got a different
set of knowledge.

And it's our job
to explain the information

in terms that they already understand.

It's no good leaving a gap
and starting from there

because they're not going to follow along.

It's better to, yeah, form the information
from what they already understand.

And how do you do this?

It's as simple as asking them
questions about what they know,

or even starting an explanation
and then asking,

"Do you already get this?,"
or, you know, "Is this making any sense?"

And if you're talking to an audience,

you have, you know,
to make your best guess,

and a show of hands can be useful too.

It's always better to err
on the side of caution.

People generally don't mind hearing
information that they already know.

Okay.

Principle two:

don't go too far down the rabbit hole.

People can only take on a certain
amount of information at any one time,

and we have to just be
realistic about that.

So, it's better to explain,
say, three things

that someone will
understand and remember

rather than barrage them
with a whole load of information

that kind of undoes all
of your good work, to begin with.

So, I could have carried on
talking about quantum physics,

but hopefully I gave you enough examples
that kind of piqued your interest

and you can go away with.

Okay.

Number three:

clarity beats accuracy.

So, when we're explaining
things with examples,

the temptation is to give the most
scientifically accurate explanation,

but they tend to be long
and kind of convoluted.

It's better to come up
with a simpler explanation

that maybe isn't completely
technically correct,

but it gets the point across.

Imagine they're here,
and the complete explanation is here.

All you want to do
is just get them along that path.

So, for example, when I was talking
about spin in quantum systems,

the truth is actually
a little bit more abstract,

of spinning in these subatomic particles,

but what I tell you is a good picture,

and, you know, if people
are still interested,

you can always iron out the details later.

Okay.

Number four:

explain why you think it's cool.

(Laughter)

If you're explaining something to someone,

you know, there's a reason
why you're doing it.

Either you think it's super important
or very, very interesting.

And the more that you can
convey that to someone,

the more likely they are to remember it
and kind of get some value from it

And you can do this in many ways.

One way is just to show
your enthusiasm for the subject.

Another way is to show, using examples,
how it's relevant to their lives.

So, for example, quantum physics:
every time you turn on your phone,

you're invoking the fundamental
laws of the universe to do your bidding -

(Laughter)

as you tweet photos of your cat.

(Laughter)

So, those are my four principles.

So, I'd just like to leave on an anecdote.

When I meet people for the first time,

and I introduce myself
and say I'm a physicist,

I get one reaction
more commonly than any other,

which is like, "Ooh, physics.
I was rubbish at physics in school."

(Laughter)

And it happens so often it's such a shame.

You know, science shouldn't be
about whether you're good at it or not.

It should only be about
whether you're interested.

And so, if you find science intimidating
or you have found science intimidating,

I just encourage you: there's so much
good information out there these days.

Just pick the subject
that you're interested in,

find some material,

and then just, from there,
follow your curiosity.

Thank you.

(Applause) (Cheers)