The frequency of collision between electrons and other particles in this region during the day is about 10 million collisions per second.

But if you look from really close up, the only problem about dancing on the head of a pin is all those big gaps between electrons.

In the nearly free electron approximation, interactions between electrons are completely ignored.

A metallic surface does it better, due to the interaction between free electrons and the photons.

The interaction between electrons and holes in this setup has an interesting side effect - it generates light!

A phylum is not a fundamental division of nature, such as the difference between electrons and protons.

The relative motion between electrons and ions is driven by rotation.

So, it is a bit misleading to think of 'space' between electrons and the nucleus.

However, the more general band theories do not consider interactions between electrons explicitly.

The gap appears due to many-body effects between electrons feeling the attraction.