Transcript:

So, at the centre of the Sun, the temperatures are insanely high. They are ranging from about 4 million Kelvin to up to 15 million Kelvin. Solid lead would start flowing, would start melting at these temperatures. They are so high.

And the way the Sun makes energy is by fusing together hydrogen to make helium. So, at these high temperatures, the hydrogen molecule, the electron, gets stripped off. It's got too much energy. It gets stripped off. You're left with protons. And these protons fuse to make helium. So, four hydrogen protons fuse to make helium. You can calculate the number of collisions that these protons are having with each other to fuse.

When you do the calculations, the answer comes out to be zero. Not one collision is happening. Yet energy is being created by fusion.

The reason that is happening is because these protons are quantum in nature. They are not localized like billiard balls. They have a wave function. And when these things come close to each other, the wave functions overlap. And a tiny, tiny fraction of the protons fuse to make helium. That's how it works.