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I want to show you a little
video of why this matters.

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So weak forces-- now, weak
forces are really strong.

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We know this because of
"Mission: Impossible".

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We know this also because
of our own students.

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There was one of my
former students, Rory,

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and he won all sorts
of prizes, because he

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was trying to be like a gecko.

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And so he made gloves that
were like gecko gloves,

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and much to the delight of
the facilities people at MIT,

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he actually climbed one of the
buildings using his gloves.

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In case you are wondering, it
wasn't actually their delight.

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But really cool stuff.

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So let me show you.

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This is like a 30-second video.

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He found the answer in the sheer
number and design of the hairs

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on the geckos feet.

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Geckos have millions
of microscopic hairs

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on their toes.

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And of course, we can't see
this with our naked eye,

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because each hair is only
1/10 the size of a human hair.

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And each of those hairs
branch down to billions

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of little split ends.

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And they can make such close
contact with the surface

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that weak intermolecular
forces can begin to add up

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to something really strong.

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Turns out geckos exploit
something called the Van der

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Waals force.

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No.

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London, London.

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If you think of an atom
as a dancing couple,

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when you bring two atoms
into very close contact,

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part of one atom can get
attracted to part of the other.

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That very weak bond is
the Van der Waals force,

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and it sticks atoms together.

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Proximity is the key.

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But bringing two materials
that near each other

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is harder than you'd think.

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All right.

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Now, obviously, that
got me very excited

40
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when I saw that, because
that is how I see atoms,

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and that is how I see electrons.

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And I saw this, and
I almost fell over.

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And of course, I played it,
and I know all those moves.

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I would suggest you guys--

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it's a Friday.

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There's some good
moves in there.

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There's some good
moves in there.

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And you can take
this on your phone

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and just kind of work
it out at the club.