Not wanting to belive the acceleration universe model

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SUMMARY

The forum discussion centers on the debate surrounding the acceleration of the universe and the validity of alternative theories to the standard model. Key papers by Wiltshire et al. and Kolb et al. propose models that challenge the necessity of dark energy and cosmic acceleration, suggesting that a moderate density of ordinary matter beyond the observable universe could explain the observed phenomena. The discussion highlights the importance of maintaining an open mind in scientific inquiry while emphasizing the need for theories to align with observational data. The skepticism surrounding these new theories is noted, particularly in light of their academic backing.

PREREQUISITES
  • Understanding of cosmological models, specifically the Friedmann equations.
  • Familiarity with Type Ia supernovae and their role in measuring cosmic distances.
  • Knowledge of general relativity and its implications for cosmological theories.
  • Awareness of the concept of dark energy and its significance in modern cosmology.
NEXT STEPS
  • Read the paper "Exact model universe fits type IA supernovae data with no cosmic acceleration" by Wiltshire et al.
  • Explore the implications of the Kolb et al. papers on dark energy and cosmic acceleration.
  • Investigate the critiques of alternative cosmological models, such as those by Geshnizjani and Hirata.
  • Study the role of observational data in shaping cosmological theories and the importance of hypothesis testing.
USEFUL FOR

Astrophysicists, cosmologists, and researchers interested in the fundamental questions of the universe's expansion and the nature of dark energy will benefit from this discussion.

  • #31
SpaceTiger said:
Again, you're mixing up proper motion and velocity. Proper motion refers to an angular motion on the sky and it's always orthogonal to an object's redshift. Nevertheless, dark matter was not invoked to explain this particular paradox, nor is it needed to resolve it, so it's just a red herring.
I apologize for the imprecise terminology, but there are hundreds, more likely thousands of papers out there written about clusters that invoke dark matter to supply the gravitational attraction need to bind clusters and keep them together. The standard model absolutely needs DM in clusters to hold them together. Indeed, many large-scale searches for DM have been modeled using cluster geometry as tracers of DM distribution. If there is a model that can explain the Fingers of God effect without invoking intrinsic redshift and without the need for DM to help bind the clusters so they don't fly apart, can you point me to the paper(s)?
 

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