whenever two media and two velocities are involved, one must follow Snell's law if one wants to take the shortest time.
Why snells law must be followed to travel diffrent media in shortest time? Does this mean that the path followed by light in travelling through different media will give a straight line if different media are transformed into like first media?I think so because one would get shortest time if one travel in a straight line.
So how does this apply to particles? Does this statement points wave particle duality?