Sorry for this little diversion, If light travels at a. different speed for different colors in order to account for the rainbow of a prism, how fast is the. speed of light then?
The speed of light is a physical constant. The frequency (or wavelength) of a photon determines its energy and therefore, to the human eye, its color.
If light's speed is a physical constant, then light wouldn't separate into colors within a prism.
Because light's speed is a physical constant, light separates into colors when passing through a prism.
The higher the frequency of a photon, the higher its energy. Since more energetic photons can not speed up, and less energetic photons can not slow down, they behave AS IF they had more or less 'mass.'
That's a fascinating view that I haven't heard proposed before. You're proposing that they DO NOT change speed, as commonly explained. The separated light would presumably lose mass, because it is now only *part* of the original.
Higher and lower energy photons deflect slightly more or less when forced to change direction in a refractive medium, in a way analogous to heavier and lighter moving objects acted on by, for instance, the wind...
That's a more parsimonious explanation -- that they have more or less energy, not speed. But I think, in fact, that this is where there is a tradeoff in the energy vs. information/data equation of the universe. Information (or data) is the opposite side of energy. Color is data, more than illumination (at least in a rainbow, where it is questionable whether it would illuminate anything). I think you answered part of my question, which was partly didactic to force science to get more rigor in its explanation. I think I will have to content myself with this because I know that rainbows and the sky being blue will NEVER be explainable by science. Mark