Cold Spot in CMB: Real or Systemic Error?

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The discussion centers on the cold spot in the Cosmic Microwave Background (CMB) and whether it represents a systemic error or a real anomaly. The cold spot is notable due to its contrast with the surrounding hotter regions, and its significance has been confirmed by the latest Planck analysis, which suggests it may have cosmological implications. Attempts to attribute the cold spot to systematic errors or local astrophysical sources have failed, indicating it is a genuine feature of the CMB. The LCDM model faces scrutiny due to this and other anomalies, raising questions about its validity. A proposed solution is the Dark Energy and Matter Gravity Coupling (DEMC) model, which may address these anomalies and align better with observed cosmic expansion rates.
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Is this a systemic error?
Quote from wiki
The cold spot is mainly anomalous because it stands out compared to the relatively hot ring around it; it is not unusual if one only considers the size and coldness of the spot itself.[7] More technically, its detection and significance depends on using a compensated filter like a Mexican hat wavelet to find it.
end quote.
Or is it real?
 
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Hmm, thanks bapowell, from the paper:

. Attempts to explain the observed features in terms of systematic artefacts, local astrophysical sources of emission, or structure in the local Universe have not been successful. It is clear that these anomalies represent real features of the CMB sky.

IS the LCDM in danger?
 
Together with the other CMB anomalies, it certainly compels a raised eyebrow. The difficulty with assigning significance to these anomalies is that even Gaussian random fields will have features that appear non-Gaussian from time to time.
 
Thank you bapowell.
I have come across this paper: Cosmology with Coupled Gravity and Dark Energy

http://arxiv.org/pdf/1409.0782.pdf

It seems to me that it explains these anomalies and deals well with other problems::

Dark energy is a fundamental constituent of our universe, its status in the cosmological field equation should be equivalent to that of matter gravity. Here we construct a dark energy and matter gravity coupling (DEMC) model of cosmology in a way that dark energy and matter are introduced into the cosmological field equation in parallel with each other from the beginning. The DEMC universe possesses a composite symmetry from global Galileo invariance and local Lorentz invariance. The observed evolution of the universe expansion rate at redshift z > 1 is in tension with the standard LCDM model, but can be well predicted by the DEMC model from measurements of only nearby epochs. The so far most precise measured expansion rate at high z is quite a bit slower than the expectations from LCDM, but remarkably consistent with that from DEMC. It is hoped that the DEMC scenario can also help to solve other existing challenges to cosmology: large scale anomalies in CMB maps and large structures up to ∼ 103 Mpc of a quasar group. The DEMC universe is a well defined mechanical system. From measurements we can quantitatively evaluate its total rest energy, present absolute radius and expanding speed.
 
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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