Sure I understand that cbr and red shift observations are real, but there is more to it. Have a read if you have not done so of Polymath's summary of bb theory, it lists some of the areas that still need resolution.
Btw, as a matter of interest, when I first read of red shift observations many decades ago, the narrative was all about it being due to the speed of the receding galaxies relative us as one looked back in time towards the bb.. But I have of late read, if I am understanding it correctly, the red shift is caused by the expansion of space in an expanding universe, with the distance between all points of space becoming larger, thus creating the red shift. Now here is my question, the earlier in time as I understand it, the less the expansion and so the less the red shift, so how is this reconciled in determining the age of the receding observed object due to red shift?
The latter description of the cosmic red shift is the correct one. For *close* galaxies, this is approximated by a doppler shift corresponding to an apparent velocity, but for larger distances/redshifts, that breaks down. In your earlier reading, only smaller redshifts had been observed.
That had changed over time. For example, we see galaxies that have redshifts over z=1, which would correspond to a velocity more than the speed of light. But the light was still able to catch up because the expansion of space itself brought the light along (the speed of light is constant *locally* in general relativity--global effects can give different results).
The red shift shows how much space has expanding since the light was emitted. So, light emitted from hydrogen (the most common element by far) has very specific wavelengths. As space expands, the wavelengths are extended and become longer. What we observe when we detect that light, may have double the wavelength of the original light from hydrogen.
But the degree of redshift is still related to how long that light has been traveling because it relates to the amount that space has expanded since that time.
In the scientific literature, distances are usually actually given by redshift. That gives relative ages and is easy to determine from observation. When distances in terms of light years or when ages are determined, though, things get more complicated. Again, the relation between redshift and age depends on the specifics of how space expanded during the time of flight of the light. So to get the actual relation between redshifts and age, we need something *else* to resolve that correspondence.
This is what 'standard candles' do. They are objects/events that have a fixed brightness no matter where they occur. Early in the study of cosmology, Cepheid variable stars were used as standard candles. Their brightness is directly correlated to how long they take to cycle. Once their brightness was known, the distance is easy to calculate. Well, for close (within a couple billion light years) things. There is a story here, but determining the brightness of the Cepheid variables was a huge undertaking for a while.
Nowadays, the distances we are probing are such that resolving individual stars, like the Cepheid variables, is impossible unless something dramatic is going on. And, dramatic things do go on: supernovas. These are incredibly bright events that can be detected across the observable universe. And, a specific type of supernova is both fairly common (in the universe as a whole) and a standard candle (as far as we know). This has allowed us to extend our distance measurements far, far further out. More accurately, the correlation between redshift and distance has been extended.
And, in fact, it was the supernova data that showed the accelerating expansion rate. And that resurrected an old, discarded, model that had a cosmological constant proposed by Einstein (another story here). That cosmological constant is equivalent to an energy density for a vacuum, which we now call dark energy.
