I know that if there was a way to compress and control air (think air bender) then it can be used to remove friction between two surfaces. A person could just skate on their feet by focusing this compressed air between their feet and ground (kind of like an ice bender creating ice floor to skate). I want to understand though, what underlying physics makes this possible? I'm guessing it is a combination of pressurized air filling-in/smoothing the roughness on ground, and thereby the reduction of friction. Or is my initial hypothesis incorrect, and skating is impossible even if we could overcome the issue of controlling wind?