Great attractor and the CMB dipole

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SUMMARY

The discussion centers on the Great Attractor and its relationship with the Dipole Repeller, highlighting the latter's dominance as a surprising finding in recent studies. The paper titled "The Dipole Repeller" (https://arxiv.org/abs/1702.02483) suggests that the universe may not be infinite, as local matter density does not balance out in all directions, challenging the cosmological principle. The conversation also references the Shapley Supercluster and the implications of cosmic flows being in tension with the Lambda Cold Dark Matter (LCDM) model, as discussed in related papers.

PREREQUISITES
  • Understanding of cosmological principles and models, particularly the LCDM model.
  • Familiarity with cosmic flow surveys and their implications.
  • Knowledge of superclusters and voids in cosmology.
  • Ability to interpret scientific papers and research findings in astrophysics.
NEXT STEPS
  • Read "The Dipole Repeller" (https://arxiv.org/abs/1702.02483) for an in-depth analysis of the findings.
  • Explore "Cosmic Flows surveys and CLUES simulations" (https://arxiv.org/abs/1205.4627) to understand cosmic flow dynamics.
  • Investigate "Frames of most uniform Hubble flow" (https://arxiv.org/abs/1607.07377) for alternative explanations of cosmic expansion.
  • Study the implications of the Shapley Supercluster on cosmic structure and density distribution.
USEFUL FOR

Astronomers, astrophysicists, and cosmologists interested in the dynamics of cosmic structures and the implications of recent findings on the nature of the universe.

Chronos
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The Great Attractor has been a source of controversy since its discovery. Some think it is just a fluke, others feel it to be a clue to a greater mystery. This paper; https://arxiv.org/abs/1702.02483, The Dipole Repeller, offers a deeper look without necessarily resolving the enigma.
 
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I don't see an enigma or mystery.
If there can be regions in the cosmos which are unusually dense, there should be other regions almost devoid of matter.
 
Is this Dipole Repeller a "supervoid"? Would it be accurate to say expansion is accelerating faster in these voids than attractor regions?

Edit: I get the sense from this article that focus on the Great Attractor has been overtaken by the Shapley Supercluster (Concentration/Attractor) and the Dipole Repeller:

Arguably, the dominance of the Dipole Repeller over the Shapley Attractor is the main novel and surprising finding of this study.
 
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The void/overdense model has baggage. It certainly suggests, imo, the universe may not be infinite. In an infinite universe the average matter density should balance out in all directions. It's hard to imagine the scale at which a local flow of such magnitude is not highly improbable without creating tension with the cosmological principle.
 
Chronos said:
It certainly suggests, imo, the universe may not be infinite. In an infinite universe the average matter density should balance out in all directions
Why would that be the case? It's like saying that since we're accelerating towards the Andromeda, the universe may not be infinite.
 
At sufficiently large scales, our measurements of cosmic flows are in tension with the LCDM model. That sounds like the makings of a mystery to me. This issue is addressed here; https://arxiv.org/abs/1205.4627, Cosmic Flows surveys and CLUES simulations. Another potential solution is offered here; https://arxiv.org/abs/1607.07377, Frames of most uniform Hubble flow.
 
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