If the following article on "phys.org" is accurate, what new model of the formation of the universe could be considered besides the Big Bang?
The article is this: https://phys.org/news/2020-06-distance-bolster-basic-universe.html
Basically, it says that, the Hubble constant latest measurements on the standard candles and the gravitationally-lensed quasars, which relates to the expansion rate of the universe, gave a value of 73–74 kilometers per second per megaparsec. However, predictions of the Hubble Constant from the standard cosmological model when applied to measurements of the cosmic microwave background (CMB)—the leftover radiation from the Big Bang—produce a value of 67.4. This means, of course, that the universe is expanding faster than expected, in other words, the “tired light hypothesis”.
Somebody could explain to me the meaning of the difference between these numbers? And, if they can’t be explained in any other way, what alternative model of the “birth” of the universe could be formed from this?
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I have always thought some version of the “tired light hypothesis” seemed more intuitive… i.e. that there is no start or edge to the universe, but you can only see so far, and that over such extreme distances as we can see, light experiences a redshift that doesn’t represent relative velocity – it’s an effect of vast distance traveled.
In pursuing this idea, I have run into three main counter-arguments which I have not mustered the energy/enthusiasm/time required to fully understand. I do accept it’s a case where people who do understand them find them compelling, though I have some lingering ideas/doubts/hypotheses that as far as I know (which I just admitted isn’t very far) leave some room for a model that would still be tired-light-like. I think it would require at least that light not just redshift over such distances, but that it produce a time-dilation-like effect on observed objects (since e.g. supernovae at the edge of observable distance seem to happen more slowly).
The main part I don’t really understand very well are the arguments about cosmic background radiation, dark matter, and what ideas around those would possibly imply. Apparently the cosmic background radiation doesn’t seem to support tired light models. Or at least, they didn’t seem to in the past. This article seems to suggest different values… but I am not able to really offer an explanation of exactly what all the implications are… I get the basics, but I think it requires more understanding that I currently have to really get. One starting point might be the part of my link above that talks about CBR.
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