Sometimes you think you have a complete understanding of something and then BOOM—a simple problem throws everything out the window. Let's consider a very basic physics problem involving pushing a ...

I'll be honest—friction is pretty complicated. Imagine that I have a block of wood sliding on a table. In some way, the atoms on the surface of the wood block are interacting with the surface atoms on ...

Cold ions sliding across periodic energy-potential patterns formed by lasers have been used to elucidate the physics of dry friction between crystals. Experiments with no more than six ions suffice to ...