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I'd like to introduce you 
to an emerging area of science.

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One that is still speculative,
but hugely exciting.

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It's certainly one that's 
growing very rapidly.

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Quantum biology asks
a very simple question.

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Does quantum mechanics, that weird
and wonderful, and powerful theory

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of the subatomic world
of atoms and molecules

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that underpins so much of modern
physics and chemistry, also play

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a role inside the living cell?

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In other words, are there processes,
mechanisms, phenomena in living organisms

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that can only be explained with a helping
hand from quantum mechanics?

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Now, quantum biology isn't new.
It's been around since the early 1930s.

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But its only in the last decade or so,
that careful experiments

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in biochemistry labs, using spectroscopy
that have shown very clear, firm evidence

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that there are certain specific mechanisms
that require quantum mechanics

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to explain them.

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Quantum biology brings together 
quantum physicists, biochemists,

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molecular biologists.

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It's a very interdisciplinary field.

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I come from quantum physics.
So, I'm a nuclear physicist.

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I've spent more than three decades trying 
to get my head around quantum mechanics.

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One of the founders of quantum 
mechanics, Neil Bohr said,

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If you're not astonished by it,
then you haven't understood it.

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So, I sort of feel happy that I'm still
astonished by it and that's a good thing.

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But it means I study the very smallest
structures in the universe.

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The building blocks of reality.

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If we think about the scale of size,
start with something, an everyday object

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like the tennis ball, and just go down
orders of magnitude and size.

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From the eye of a needle, down to a cell,
down to a bacterium, down to an enzyme.

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You eventually reach the nano world.

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Now, nanotechnology may 
be a term you've heard of.

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A nanometer is 
a billionth of a meter.

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My area is the atomic nucleus,
which is the tiny dot inside an atom.

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It's even smaller in scale.

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This is the domain of quantum mechanics,
and physicists and chemists have had

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a long time to get used to it.

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Biologists on the other hand
have got off lightly, in my view.

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They are very happy with their 
balls-and-sticks models of molecules.

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(Laughter)

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The balls are the atoms, the sticks
are the bonds between the atoms

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and when they can't build them
physically in the lab,

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nowadays they have very powerful
computers that will simulate a huge model.

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This is a protein made up 
of 100,000 atoms.

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It doesn't really require much in the way 
of quantum mechanics to explain it.

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Quantum mechanics was 
developed in the 1920s.

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It is a set of beautiful and powerful 
mathematical rules and ideas

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that explain the world
of the very small.

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And it's a world that very different
from our everyday world

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made up of trillions of atoms.

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It's a world built on probability
and chance.

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It's a fuzzy world.

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It's a world of phantoms, where particles
can also behave like spread out waves.

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If we imagine quantum mechanics
or quantum physics, then as

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the fundamental 
foundation of reality itself.

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That's not surprising 
that we say quantum physics

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underpins organic chemistry.

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After all, it gives us
the rules that tells us

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how the atoms fit together
to make organic molecules.

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Organic chemistry, scaled up in complexity
gives us molecular biology,

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which of course leads 
to life itself.

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So, in a way, it's sort 
of not surprising.

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It's almost trivial.

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Say, well of course life ultimately
must depend of quantum mechanics.

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But, so does everything else.

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So does all inanimate matter, 
made up of trillions of atoms.

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Ultimately, there's a quantum level
that we know where we have to delve

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into this weridness.

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But in everyday life, 
we can forget about it.

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Because once you put together trillions 
of atoms, that quantum weirdness

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just dissolves away.

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Quantum biology isn't about this.
Quantum biology isn't this obvious.

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Of course quantum mechanics underpins
life at some molecular level.

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Quantum biology is about looking
for the non-trivial, the counterintuitive

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ideas in quantum mechanics and to see
if they do indeed play an important role

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in describing the processes of life.

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Here is my perfect example
of the counterintuitiveness

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of the quantum world.

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This is the quantum skiier.

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He seems to be intact, he seems
to be perfectly healthy.

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And yet, he seems to have gone around
both sides of that tree at the same time.

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Well, if you saw some tracks like that
you'd guess some sort of stunts of course.

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But in the quantum world,
this happens all the time.

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Particles can multitask, they can be
in two places at once.

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They can do more than
one thing at the same time.

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Particles can behave
like spread out waves.

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It's almost like magic.

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Physicists and chemists have had
nearly a century of trying

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to get used to this weirdness.

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I don't blame the biologists for not
having or wanting to learn

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quantum mechanics.

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You see, this weirdness is very delicate
and we physicists work very hard

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to maintain it on our labs.

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We sort of cool our system down
to near absolute zero,

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We carry out our experiments 
in vacuums, we try and isolate it

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from any external disturbance.

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That's very different from the warm,
messy, noisy environment of a living cell.

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Biology itself, if you think of molecular
biology, seems to have done very well

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in describing all the processes of life,
in terms of chemistry.

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Chemical reactions!

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And these are reductionist, deterministic
chemical reactions showing that

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essentially life, is made of the same
stuff as everything else,

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and if we can forget about quantum 
mechanics in the macro world,

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then we should be able to forget 
about it in biology, as well.

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Well, one man begged 
to differ with this idea.

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Erwin Schrödinger, he of Schrödinger's Cat
fame, an Austrian physicist.

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He was one of the founders
of quantum mechanics in the 1920s.

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In 1944, he wrote a book
called "What is Life?"

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It was tremendously influential.

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It influenced Francis Crick
and James Watson,

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the discoverer's of the double helix
structure of DNA.

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To paraphrase a description in the book,
he says, at the molecular level,

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living organism have a certain order,
a structure to them that's very

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different from the random thermodynamic
jostling of atoms and molecules

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in inanimate matter 
of the same complexity.

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In fact, living matter seems to behave
in its order, in its structure

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just like inanimate matter cooled
down to near absolute zero,

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where quantum effects 
play a very important role.

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There's something special about
the structure, the order

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inside a living cell.

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So, Schrödinger speculated that maybe
quantum mechanics plays a role in life.

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It's a very speculative, sort of
far-reaching idea and it didn't

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really go very far.

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But, as I mentioned at the start,
in the last 10 years

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there have been experiment emerging,
showing where some of these certain

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phenomena in biology, do seem
to require quantum mechanics.

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I want to share with you
just a few of the exciting ones.

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This is one of the best known 
phenomena in the quantum world.

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Quantum tunneling.

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The box on the left, shows the wavelike
spread out distribution of quantum entity.

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A particle, like an electron.

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Which is not a little ball 
bouncing off a wall.

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It's a wave that has a certain probability
of being able to permeate through

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a solid wall, like a phantom 
leaping through to the other side.

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You can see a faint smudge of light
in the right hand box.

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Quantum tunneling suggests that a particle
can hit an impenetrable barrier and yet,

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somehow, as if by magic, disappear from
one side and reappear on the other.

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The nicest way of explaining it,
is if you want to throw a ball

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over a wall, you have to give it enough
energy to get over the top of the wall.

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In the quantum world, you don't have
to throw it over the wall.

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You can throw it at the wall and three's
a certain non-zero probability that it'll

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disappear on your side,
and reappear on the other.

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This isn't speculation, 
by the way, we're happy

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-- I'm sorry, happy is not the right word.

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(Laughter)

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We are familiar with this.

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(Laughter)

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Quantum tunneling takes place 
all the time, in fact

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it's the reason our sun shines.

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The particles fuse together in the sun
is turning hydrogen into helium

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through quantum tunneling.

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Back in the 70s and 80s, it was discovered
that quantum tunneling also takes place

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inside living cells.

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Enzymes, those workhorses of life,
the catalysts of chemical reaction.

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Enzymes are biomolecules that speed
up chemical reactions in living cells.

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By many, many orders of magnitude.

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And it's always been a mystery
how they do this.

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Well, it was discovered that one
of the tricks that enzymes have evolved

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to make use of, is by transferring
subatomic particles, like electrons

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and indeed protons, from one part
of a molecule to another via

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quantum tunneling.

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It's efficient, it's fast, 
it can disappear

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-- a proton can disappear from one place
and a reappear on the other.

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Enzymes help this take place.

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This is research that's been carried out
back in the 80s, particularly by a group

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in Berkeley, Judith Klinman.

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Other groups in the UK have now also
confirmed that enzymes really do this.

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Research carried out by my group
-- so I mentioned I'm a nuclear physicist,

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but I've realize I've got these tools
of using quantum mechanics

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in atomic nuclei and so can apply those
tools in other areas, as well.

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One question we asked was, whether 
quantum tunneling plays a role

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in mutations in DNA.

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Again, this is not a new idea.
It goes all the way back to the early 60s.

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The two strands of DNA, the double helix 
structure are held together by rungs,

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it's like a twisted ladder.

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And those rungs of the ladder
are hydrogen bonds.

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Protons that act as the glue
between the two strands.

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So, if you zoom in, what they're doing
is holding these large molecules,

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nucleotides, together.

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Zoom in a bit more.

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So, this a computer simulation.

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The two white balls in the middle
are protons and you can see that

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it's a double hydrogen bond.

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One prefers to sit one side, 
the other on the other side of the stands.

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The two strands of the vertical lines
going down, which you can't see.

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It can happen that these 
two protons can hop over.

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Watch the two white balls.
They can jump over to the other side.

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If the two strands then separate,
leading to the process of replication,

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and the two protons are in the wrong
positions, this can lead to a mutation.

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This has been known for half a century.

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The question is how likely can they do 
that, and if they do, how do they do it?

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Do they jump across, like the ball
going over the wall?

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Or can they quantum tunnel across,
even if they don't have enough energy?

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Early indications suggest that quantum
tunneling can play a role here.

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We still don't know yet how important
it is, it's still an open question.

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It's speculative, but it's one of those 
questions that it is so important,

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that if quantum mechanics plays
a role in mutations, surely this must

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have big implications, to understand
certain types of mutations, possibly even

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those that lead to turning 
a cell cancerous.

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Another example of quantum mechanics
in biology is quantum coherence

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in one of the most important process
in biology, photosynthesis.

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Plants and bacteria taking sunlight,
using that energy to create biomass.

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Quantum coherence is the idea
of quantum entities multitasking.

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It's the quantum skier.

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It's an object that behaves like a wave,
so that it doesn't just move

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in one direction or the other, but can
follow multiple pathways at the same time.

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Some years ago, the world of science
was shocked when a paper was published

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showing experimental evidence,
that quantum coherence takes place

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inside bacteria, 
carrying out photosynthesis.

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The idea is that the photon, 
the particle of light, the sunlight,

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the quantum of light, captured by 
a chlorophyl molecule, is then delivered

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to what's called the reaction center where
it can be turned into chemical energy.

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And in getting there, it doesn't just
follow one root, it follows multiple

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pathways at once, to optimize the most
efficient way of reaching the reaction

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center, without dissipating 
as waste heat.

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Quantum coherence taking place
inside a living cell.

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A remarkable idea, and yet evidence
is growing almost weekly with new papers

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coming out, confirming that 
this does indeed take place.

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My third and final example is the most
beautiful, wonderful idea.

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It's also still a very speculative,
but I have to share it with you.

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The European Robin migrates from
Scandinavia, down to the Mediterranean

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every autumn and like a lot of other
marine animals and even insects,

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they navigate by sensing 
the Earth's magnetic field.

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Now the Earth's magnetic 
field is very, very weak.

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It's 100 times weaker than
a fridge magnet and yet

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it affects the chemistry, somehow,
within a living organism.

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That's not in doubt, 
a German couple of onothologists

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Wolfgang and Roswitha Wiltschko,
in the 1970s confirmed that indeed

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the robin does find it's way by somehow
sensing the Earth's magnetic field,

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to give it directional information,
a built-in compass.

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The puzzle, the mystery was
how does it do it?

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Well, the only theory in town,
we don't know if it's the correct theory,

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but the only theory in town, is that
it does it via something called

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quantum entanglement.

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Inside the robin's retina
-- I kid you not.

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Inside the robin's retina, 
is a protein called cryptochrome,

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which is light sensitive.

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Within cryptochrome, a pair of electrons
are quantum entangled.

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Now quantum entanglement is when two
particles are far apart and yet somehow

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remain in contact with each other.

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Even Einstein hated that idea, he called
it spooky action at a distance.

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(Laughter)

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If Einstein doesn't like it, then we can
all be uncomfortable with it.

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Two quantum entangled electrons within
a single molecule, dance a delicate dance

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that is very sensitive 
to the direction the bird flies

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in the Earth's magnetic field.

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We don't know if it's the correct
explanation, but wow wouldn't it be

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exciting if quantum mechanics
helps birds navigate.

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Quantum biology is still in it infancy.
It's still speculative.

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But I believe it's built on solid science.

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I also think that in the coming decade,
or so, we're going to start to see

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that actually it pervades life, that life
has evolved tricks that utilize

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the quantum world.

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Watch this space.

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Thank you.

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(Applause)