Friction and Relation of Coefficient of Friction to "Smoothness" In my physics class today my teacher began discussing a very peculiar characteristic concerning the static and dynamic coefficients of friction. Apparently, when one makes an object's surface "smoother" (meaning with less impurities and a more uniform surface), the coefficient decreases to a certain point. However, past that point of "smoothness," the smoother the object becomes, the greater the coefficient of friction becomes. Apparently Japanese scientists have machines for this purpose unlike anywhere else in the world that make the surface of an object look uniform, even to a scanning electron microscope, and yet have a quite high coefficient of friction. My teacher said that there were several theories as to why this strange phenomenon occurred, such as a theory that the uniformity of the object's surface creates a uniform electron spin that interferes with the spin of another object placed upon it. However, others say that this and other theories don't hold any water. If anyone has any examples or other theories that explain why this weird and surprising (to me) quirk appears, I would appreciate your input. This is my first post, so I hope you all can cut me some slack.