In terms of a ray-tracing problem, it's hard to understand how light that's incident below the eye ends up in the eye. It also seems to be a much more common practice among football players than baseball players. The key question is does it make any difference in performance? I find that a...
Grease under the eyes of football players -- dumb or not?
Maybe this is silly question, but why do football players put grease under their eyes? I've always assumed that it's supposed to reduce glare, but this seems to make little sense considering the angle of the incident light, which mostly...