When I was in science, my teacher was talking about the periodic table and atoms me and a fellow student wondered, what IS the empty space inside an atom (between the nucleus and the electrons)? Is it possible that there is nothing in that space, or could this question lead to particles smaller than quarks? Maybe it's dark matter. I'm not sure. Does anyone have theories or possible add-ons for this question? It's weird that there could be smaller particles than quarks, or that it is possible for some things to be made of nothing, maybe this could prove dark matter's existence!