The cosmic model I prefer is an observable universe as relative to an integral part of an infinite one, fading out of view at the Schwartzschild radius of the observable part. Tired light fits this model, as for resoving Olber's paradox for both light and gravity. I considered two possibilities: (1) the reduction of light energy is the same for all light; (2) the reduction is proportionally the same for all light. I preferred (1), but (2) seems the end result of observation.
I read more in your Big Bang Blasted and pages 220 and 223 caught my eye. Page 220 seemed confusing, at first, relating to possibility (1). The increase in wavelenth for all wavelengths is h/mc, which I recognized as the Compton wavelenth in the hydrogen atom. In contrast, page 223 is for possibility (2), where the increase in wavelength is proportional to the wavelength being increased.
I was confused until I reread for more detail and the light finally came into my head. Possibility (1) occurs with each encouter with an individual electron, whereas possibility (2) occurs because the number of encounters is proportional to the wavelength. Both possibilities are possible without contradiction.
