What ideas does the discrepancy of CMB photons affect?

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The article discusses an unexpected increase in cosmic microwave background (CMB) radiation near galaxy clusters, contradicting cosmological theories that predict a deficit due to interactions with these clusters. This phenomenon relates to the Sunyaev-Zel'dovich effect, which suggests that CMB photons should gain energy but are not being detected as expected. Current observations indicate that the detected signal is only 0.5-0.7 times what simulations and calculations predict, particularly in low mass clusters. This discrepancy implies a need for a deeper understanding of cluster gas dynamics and could prompt a reevaluation of existing cosmological models. The ongoing confusion highlights the complexity of interpreting CMB data in relation to galaxy clusters.
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An article on news.discovery.com titled, "The Universe is Precisely 13.75 Billion Years Old" on Feb. 4 says:

"The amount of CMB radiation spotted near clusters of galaxies is greater than expected. According to [cosmological] theory, CMB photons should interact with these clusters, getting kicked to higher energies. WMAP cannot detect these higher energy photons, so there should be a deficit of CMB photons around clusters. This is not the case and scientists will probably be confused by this for some time to come."

What ideas of cosmological theory might this make us rethink?
 
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Space news on Phys.org
For anyone wanting to read the full article it can be found http://news.discovery.com/space/the-universe-is-precisely-1375-billion-years-old.html".

In answer to your question, it is a bit confusing as this pop-sci article doesn't mention enough specifics to know what it is referring to exactly (i.e. what study has found a discrepancy?). What is being referred to is the Sunyaev-Zel'dovich effect, and we have observed this in clusters (for instance read up on the South Pole Telescope). I'm not completely sure what the latest observational data of the SZ effect says, but I wasn't aware of any glaring discrepancies to date?
 
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The WMAP results are not discrepant with other SZ observations. The problem is that the detected signal is 0.5-0.7 times that predicted from simulations, analytical calculations and X-ray observations. The result is more significant for low mass clusters and means we probably don't fully understand the cluster gas.
 
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
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