Another age problem in the early universe?

In summary, a recent study has identified 59 massive structures of galaxies at high redshifts, with a discrepancy between the observed number densities and those predicted by the ΛCDM cosmological model. This suggests that there may be too many massive structures at high redshifts compared to the standard model, and further research is needed to explain this discrepancy.
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Garth
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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
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.
(emphasis mine)

Garth
 
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Given the variance is sensitive to the assumptions employed in the Millenium simulation, this result is not altogether surprising. We already knew, for example, that the apparent mass of high z black holes that power ancient quasars is a challenge to explain under LCDM, so it is reasonable to expect the answer to both enigmas is probably related.
 
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As they say in the conclusions of the article Garth quoted:
" 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 ΛCDM cosmology framework. ..."

It sounds like what we have here is a tweaking problem---adjusting the initial conditions of the standard cosmic model to get a better fit to all the data.
 

1. What is the "age problem" in the early universe?

The "age problem" refers to the discrepancy between the estimated age of the universe and the age of the oldest objects in the universe. According to the Big Bang theory, the universe is approximately 13.8 billion years old, but some of the oldest objects such as globular clusters have been found to be around 13.2 billion years old. This inconsistency raises questions about the accuracy of our understanding of the early universe.

2. How does this age discrepancy affect our understanding of the universe?

The age discrepancy challenges our current models and theories about the early universe. It suggests that there may be aspects of the Big Bang theory that we do not fully understand or that there may be other factors at play that are influencing the age of the universe and its objects.

3. What are some potential explanations for the age problem in the early universe?

There are several proposed explanations for the age problem, including the possibility of errors in our measurements and calculations, the existence of dark energy that is accelerating the expansion of the universe, and the presence of new physics that we have not yet discovered.

4. How do scientists study and try to solve this age problem?

Scientists use a variety of methods to study and try to solve the age problem, including analyzing data from telescopes and satellites, conducting experiments in particle accelerators, and developing new theories and models to better understand the early universe.

5. What implications does the age problem have for our understanding of the future of the universe?

The age problem has significant implications for our understanding of the future of the universe. It suggests that our current models and predictions about the fate of the universe may not be entirely accurate and that there may be unknown factors that could influence its ultimate fate. Further research and study of the age problem may help us gain a better understanding of the long-term evolution of the universe.

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