Humans can feel molecular differences between nearly identical surfaces
Knew it! Yes!
Stick-slip ! My intuition held up. That was my favorite area of research. Now I can return to it.
“According to the researchers, human subjects can feel these differences because of a phenomenon known as stick-slip friction, which is the jerking motion that occurs when two objects at rest start to slide against each other. This phenomenon is responsible for the musical notes played by running a wet finger along the rim of a wine glass, the sound of a squeaky door hinge or the noise of a stopping train. In this case, each surface has a different stick-slip frequency due to the identity of the molecules in the topmost layer”