I'd like to introduce you to an emerging area of science. One that is still speculative, but hugely exciting. It's certainly one that's growing very rapidly. Quantum biology asks a very simple question. Does quantum mechanics, that weird and wonderful, and powerful theory of the subatomic world of atoms and molecules that underpins so much of modern physics and chemistry, also play a role inside the living cell? In other words, are there processes, mechanisms, phenomena in living organisms that can only be explained with a helping hand from quantum mechanics. Now, quantum biology isn't new. It's been around since the early 1930s. But its only in the last decade or so, that careful experiments in biochemistry labs, using spectroscopy that have shown clear, firm evidence that there are certain specific mechanisms that require quantum mechanics to explain them. Quantum biology brings together quantum physicists, biochemists, molecular biologists. It's a very interdisciplinary field. I come from quantum physics. So, I'm a nuclear physicist. I've spent more than three decades trying to get my head around quantum mechanics. One of the founders of quantum mechanics, Neil Bohr said, If you're not astonished by it, then you haven't understood it. So, I sort of feel happy that I'm still astonished by it and that's a good thing. But it means I study the very smallest structures in the universe. The building blocks of reality. If we think about the scale of size, start with something, an everyday object like the tennis ball, and just go down orders of magnitude and size. From the eye of a needle, down to a cell, down to a bacterium, down to an enzyme. You eventually reach the nano world. Now, nanotechnology may be a term you've heard of. A nanometer is a billionth of a meter. My area is the atomic nucleus, which is the tiny dot inside an atom. It's even smaller in scale. This is the domain of quantum mechanics, and physicists and chemists have had a long time to get used to it. Biologists on the other hand have got off lightly, in my view. They are very happy with their balls-and-sticks models of molecules. (Laughter) The balls are the atoms, the sticks are the bonds between the atoms and when they can't build them physically in the lab, nowadays they have very powerful computers that will simulate a huge model. This is a protein made up of 100,000 atoms. It doesn't really require much in the way of quantum mechanics to explain it. Quantum mechanics was developed in the 1920s. It is a set of beautiful and powerful mathematical rules and ideas that explain the world of the very small. And it's a world that very different from our everyday world made up of trillions of atoms. It's a world built on probability and chance. It's a fuzzy world. It's a world of phantoms, where particles can also behave like spread out waves. If we imagine quantum mechanics or quantum physics, then as the fundamental foundation of reality itself. That's not really surprising that we say quantum physics underpins organic chemistry. After all, it gives us the rules that tells us the rules that tell us how the atoms fit together to make organic molecules. Organic chemistry, scaled up in complexity gives us molecular biology, which of course leads to life itself. So, in a way, it's sort of not surprising. It's almost trivial. Say, well of course life ultimately must depend of quantum mechanics -- so does everything else. So does all inanimate matter, made up of trillions of atoms. Ultimately, there's a quantum level that we know where we have to delve into this weridness. But in everyday life, we can forget about it. Because once you put together trillions of atoms, that quantum weirdness just dissolves away. Quantum biology isn't about this. Quantum biology isn't this obvious. Of course quantum mechanics underpins life at some molecular level. Quantum biology is about looking for the non-trivial, the counterintuitive ideas in quantum mechanics and to see if they do indeed play an important role in describing the processes of life. Here is my perfect example of the counterintuitiveness of the quantum world. This is the quantum skiier. He seems to be intact, he seems to be perfectly healthy. And yet, he seems to have gone around both sides of that tree at the same time. Well, if you saw some tracks like that you'd guess some sort of stunt of course. But in the quantum world, this happens all the time. Particles ca multitask, they can be in two places at once. They can do more than one thing at the same time. Particles can behave like spread out waves. It's almost like magic. Physicists and chemists have had nearly a century of trying to get used to this weirdness. I don't blame the biologists for not having or wanting to learn quantum mechanics. You see, this weirdness is very delicate and we physicists work very hard to maintain it on our labs. We sort of cool our system down to near absolute zero, We carry out our experiments in vacuums, we try and isolate it from any external disturbance. That's very different from the warm, messy, noisy environment of a living cell.