A Quantum Snippet from Jim Al-Khalili’s TEDGlobal talk

Deb Maes - Tuesday, August 25, 2015

Capture1TEDGlobalLondon · Filmed June 2015 · 16:09 Jim Al-Khalili: How quantum biology might explain life’s biggest questions

He starts with, ‘I’d like to introduce you to an emerging area of science, one that is still speculative but hugely exciting, and 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 it’s only in the last decade or so that careful experiments — in biochemistry labs, using spectroscopy — have shown very clear, firm evidence that there are certain specific mechanisms that require quantum mechanics to explain them.

‘I’ve spent more than three decades trying to get my head around quantum mechanics. One of the founders of quantum mechanics, Niels 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. 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 an everyday object like the tennis ball, and just go down orders of magnitude in 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 try and 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.’

Ultimately, there’s a quantum level where we have to delve into this weirdness. 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.

He gives a few examples of how. His final third example I agree is the most beautiful and wonderful idea. He says, ‘It’s also still very speculative, but I have to share it with you. The European robin migrates from Scandinavia down to the Mediterranean, every autumn, and like a lot of other marine animals and even insects, they navigate by sensing the Earth’s magnetic field. Now, the Earth’s magnetic field is very, very weak; it’s 100 times weaker than a fridge magnet, and yet it affects the chemistry — somehow — within a living organism. That’s not in doubt — a German couple of ornithologists, Wolfgang and Roswitha Wiltschko, in the 1970s, confirmed that indeed, the robin does find its way by somehow sensing the Earth’s magnetic field, to give it directional information — a built-in compass.

The mystery was: How does it do it?

Well, the only theory in town — we don’t know if it’s the correct theory, but the only theory in town — is that it does it via something called quantum entanglement. Inside the robin’s retina — I kid you not — inside the robin’s retina is a protein called cryptochrome, which is light-sensitive. Within cryptochrome, a pair of electrons are quantum-entangled.

I love this part,  ‘quantum entanglement is when two particles are far apart, and yet somehow remain in contact with each other. Even Einstein hated this idea; he called it “spooky action at a distance.”‘

‘So if Einstein doesn’t like it, then we can all be uncomfortable with it. Two quantum-entangled electrons within a single molecule dance a delicate dance that is very sensitive to the direction the bird flies in the Earth’s magnetic field.

‘We don’t know if it’s the correct explanation, but wow, wouldn’t it be exciting if quantum mechanics helps birds navigate? Quantum biology is still in it infancy. It’s still speculative. But I believe it’s built on solid science. I also think that in the coming decade or so, we’re going to start to see that actually, it pervades life — that life has evolved tricks that utilize the quantum world. Watch this space.’