What if you could shrink yourself
down to 1 mm (0.04 in) tall,
about the size of a frog's egg?
Actually no,
too many creepy crawly predators,
let’s go smaller.
What if you shrunk to 10 micrometers (0.0004 in),
the size of an animal cell.
That's pretty cool,
but I think we can go even smaller.
How about 100 nanometers (0.000004 in),
the size of a virus?
That’s better, but we're not in the mood
to be swallowed by white blood cells.
So let's keep going.
What if you shrunk to 1 angström,
the size of the atom?
Oh yeah,
I think we have a winner.
If you shrunk to the size of an atom,
would it be a fantastic voyage?
Or a death sentence?
From "Gulliver's Travels"
to "Alice in Wonderland"
to "Ant-man,"
the idea of shrinking
has fascinated us for a long time.
The atom, in all its splendor, is tiny.
I mean really, really tiny.
Measuring in at 1 angström.
To put that in perspective,
if you were to blow up an atom 1 billion times,
it would only get as big as a tennis ball.
While shrinking seems like
it would be an amazing superpower,
it would actually be a deadly fight for survival.
The first hurdle you’re going to have to deal with
is your mass.
If you shrunk without changing your mass,
there would be so much compression
that for an ant-sized person,
the pressure underneath your tiny feet
would be ten thousand times greater
than at your normal size.
It would be like a single, ant-sized leg
pushing down 70 kg (155 lbs) on each step.
Next, you would have to deal with your body
turning against you.
Your new, smaller size
will affect almost every aspect of your biology.
For example,
if you shrunk be approximately 2.5 cm (1 in) tall,
the surface area of your body,
through which you lose heat,
would decrease about 5,000 times.
Your lung area would be 5,000 times smaller,
but you could still get
the supply of oxygen you need.
The way you extract oxygen from the air
is dependent on the surface area of your lungs.
As you get smaller
the area of your lungs is larger
than the volume of your lungs,
which means there's more than enough
air to go around.
But you’re not out of the woods yet.
You would need to provide your body
with more fuel,
a lot more fuel.
This is because
the rate at which you produce heat
is proportional to the mass of your body.
The only way to generate more heat
is to increase your metabolic rate dramatically!
This means you have to eat nonstop
as the food needs to be digested
in order to produce heat.
You would have to eat as much food
as your body weighs,
every day, just to stay alive.
And this is just for a 2.5 cm (1 in)
version of you.
You'll have even more dangers to face
when you’re atom-sized.
During your shrinking process,
you’ll notice the world getting bigger …
and then darker.
It's estimated that if you decreased in size
to approximately one 10,000th of your size,
the lenses in your eyes would stop working
in just-visible light.
Or, that may just be you passing out.
When you take the big step
of squeezing your feet into microscopic shoes,
one single oxygen molecule
will look like Mount Everest to you.
You're literally smaller than an oxygen molecule.
How long can you hold your breath?
So, if you feel up to the challenge,
could you even pull this off?
The big problem with shrinking down
to the size of an atom
is that the atoms in your body
can’t be made any smaller.
And your body contains more atoms
than the number of stars
we can see in the Universe.
You’d have to remove some excess baggage.
Is it possible to remove
the atoms in your body?
Imagine a mosaic image,
a picture made entirely out of smaller pictures.
Much like these images,
our body consists of DNA,
built up by molecules consisting of atoms.
If you started removing pictures
from your mosaic image,
you might be able to remove a few
and still see a resemblance to the original.
But there is a limit.
After a while,
the image would no longer make sense.
This is also true of DNA.
We might be able to remove atoms
from the molecules building up the DNA,
but eventually ,we would reach a limit
and make a mess of your human body.
So until you solve that problem,
no shrinking for you.
But if you manage to conquer all the challenges,
you would be able to experience
the insane world of quantum mechanics.
If you could learn to live in this environment,
you could have a blast tunneling
and jumping through impenetrable barriers
on your path to chart the microverse.
Truth be told though,
it's probably easier living at the size we are.
Mostly because we don’t have to deal
with things like giant spiders.
But what if that wasn’t the case?
What if spiders were the size of humans?
Well, that’s a story for another WHAT IF.