Horizon scale at the onset of cosmic acceleration

In summary: XivIn summary, the lack of large-scale correlations in the cosmic microwave background (CMB) at the horizon scale of cosmic acceleration poses a challenge to generic inflationary models and potentially even the validity of general relativity on the observable universe scale. While the deficiency of large-angle anisotropies may be attributed to statistical flukes, the significant deficiencies in quadrupole and octopole modes, along with their alignment to local geometry, suggest a possible gravitational lensing effect by local matter. This could indicate a very deficient CMB power spectrum in these modes, causing trouble for the mainstream LCDM model. However, this problem can be resolved without completely discarding the current cosmological paradigm, but rather
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turbo
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http://www.arxiv.org/PS_cache/astro-ph/pdf/0508/0508047.pdf

paper said:
It is at least amusing to note that the scale on which the lack of large scale correlations is then manifested is comparable to the horizon scale at the onset of cosmic acceleration. At the least this profound lack of large-angle correlations would further challenge generic inflationary models, maybe even general relativity on the scale of the observable universe will need to be reconsidered.
 
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We have already discussed this subject here.

The large angle low l-mode anisotropies are few in number and therefore their deficiency might be a statistical fluke. However the quadrupole and octopole deficiencies are significant to high sigma. If they are also aligned to local geometry as they appear to be, possibly caused by a gravitational lensing of the much larger CMB dipole by the motion of local matter, our galactic cluster and supercluster(?), then the CMB anistropy power spectrum is very deficient at these modes. The mainstream LCDM model would be in trouble in this case.

To resolve the problem one does not need to throw out the whole cosmological paradigm but adapt it. The power-spectrum peaks are consistent with a flat universe, the absence of low l-modes is consistent with a finite universe.

As I have repeatedly said the data is consistent with a finite conformally flat model, as predicted by Self Creation Cosmology as well as other more exotic topologies such as the http://www.nature.com/nature/journal/v425/n6958/abs/nature01944.html;jsessionid=9C2E90589BD72EC42B0FA3AE831B62CA 'soccer ball' model.
Garth
 
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1. What is the horizon scale at the onset of cosmic acceleration?

The horizon scale at the onset of cosmic acceleration refers to the distance at which objects in the universe begin to recede from each other faster than the speed of light. This is known as the cosmic event horizon and is estimated to be about 14 billion light years away from us.

2. How does the horizon scale relate to the expansion of the universe?

The horizon scale is closely tied to the expansion of the universe because it marks the point at which the expansion of the universe begins to accelerate due to the mysterious force known as dark energy. This acceleration causes the horizon scale to increase over time.

3. How is the horizon scale calculated?

The horizon scale is calculated using the Hubble parameter, which is a measure of the current rate of expansion of the universe, and the critical density of the universe. It also takes into account the amount of dark energy present in the universe.

4. Why is the horizon scale important in understanding the universe?

The horizon scale is important because it gives us insight into the expansion and structure of the universe. It helps us understand how objects in the universe are moving in relation to each other and how the universe has evolved over time.

5. How has the horizon scale changed over time?

The horizon scale has increased over time as the universe continues to expand at an accelerating rate. This means that the horizon scale today is much larger than it was in the past, and it will continue to increase in the future.

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