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I have on several occasions on PF flagged up examples where it appears that there is an age problem in the early universe, in other words highly evolved objects have been observed whose existences are difficult to explain at their high red shifts in the standard [itex]\Lambda[/itex]CDM cosmological model.
Another example has been recently published in the Journal of the Korean Astronomical Society (48: 21-55, February 2015) and on the physics arXiv Massive Structures of Galaxies at High Redshifts in the Great Observatories Origins Deep Survey Fields
Garth
Another example has been recently published in the Journal of the Korean Astronomical Society (48: 21-55, February 2015) and on the physics arXiv Massive Structures of Galaxies at High Redshifts in the Great Observatories Origins Deep Survey Fields
(emphasis mine)8. CONCLUSIONS
Using the multi-wavelength data, we identied 59 Massive Structures of Galaxies (MSGs) from the combined areas of the GOODS-South and the GOODS-North fields with signicances of 3:5 - 8 [itex]\sigma[/itex] from z = 0:6 to z ~ 4:5. Among them, ~20% of MSGs show plausible associations with AGN/radio sources.
In comparison with a simulation data set, we find a discrepancy between the observed number densities of MSGs and those from the simulation at z > 1 (M > 7 X 1013M[itex]\odot[/itex] ). The discrepancy becomes more signicant at higher redshifts (z > 2) by a factor of ~5 or more. Even after considering possible systematic effects, our result implies that there are too many massive structures at z > 2 compared to the [itex]\Lambda[/itex]CDM prediction. By tweaking the conditions for the initial density fluctuation or baryonic physics in galaxy formation, one may be able to explain the result within the [itex]\Lambda[/itex]CDM cosmology framework, but as of now the overabundance of MSGs at z > 2 stands as a challenge to the models based on the [itex]\Lambda[/itex]CDM cosmology.
Garth
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