Originally Posted By: redewenur
So, to recap, while you have no idea what causes the redshift, you're sure that it's not recessional velocity?

I believe that my comment to the effect that when light travels via the random matter in space and creates an increase in that matter's temperature leaving itself slightly energy depleted - i.e. redshifted - IS an expression of my opinion as to what causes the redshift!

I made NO suggestion that the redshift is not due to recessional velocity but pointed out that the energy loss may RESULT in recessional velocity!