Rays and wave fronts are the same thing. There is no interaction between light and matter. The addition of all colors of light yields black. Double slit interference shows light wave crest and troughs. Light exits in the crest of a wave and dark in the trough.
Refraction is the bending of waves.
The aether exists because something must transmit light. Postulates cannot be used to develop a theory. Length, mass, and time changes are just apparent. Time is absolute. Length and time only change for one observer.