I was watching this Stephen Hawking documentary recently and they had a really awkward scene where a group of his students and he were sitting around some living room eating and laughing and having a good time. Hawking was eating too, but he was being fed by some care giver. They never actually showed him eating. They showed her moving toward his mouth with a spoon, but not actually eating. Probably because it's one of those things you wish you could un-see. It was really gratuitous. The camera would generously show these students laughing and enjoying their food, then Hawking from the back of his wheel chair.

Anyway, There was another physicist on there that was explaining a very interesting thing about atoms. If you inflated an atom (for the sake of illustration) until its nucleus was the size of a marble, its electron would be the width of a hair. The electron, of coarse, orbits the nucleus. At the scale of the marble and the hair, how far away would you say the hair would be from the marble to be accurately to scale? Think about it first. Look around you, and look at your self, your physical body. Look at the ground, feel the solidness of your chair. Everything is made up of atoms. They are, as far as we can tell, all there is to make stuff out of.

At the scale where the nucleus is the size of a marble and the orbiting electron is the width of a hair, the electron would orbit about two miles away from the marble sized nucleus. All the rest is empty space. Atoms touch (unless under extreme circumstances) at the electron orbit. That means that the nucleus is this tiny, tiny little thing, just floating there in this vast empty space, almost not existing.

We are all made of this stuff. Almost nothing. It's mathematically provable.