Population III stars have low metallicity, so how would they explain the high metallicity of this old cluster?Chronos said:. We know they are 'old' because of high metallicity in their spectrums... I think this can, at least in part, be explained by the abundance of population III stars in the early universe.
Yes, but I sometimes see these tight estimates as a little drawback of the model. To have all the parameters(dark matter, dark energy, baryonic matter, flatness, age...) so highly constrained (finely tuned) make it appealing on one hand (precision cosmology) and very sensitive to discordant observations such as finding old galaxies with ever higher redshift pushing back the age) on the other, because if one changes one parameter, the rest has to change too.Chronos said:.
It is a mystery because we are fairly confident of our estimates of the age of the universe.
Chalnoth said:Personally, I think that ultimately these issues will be resolved with a better understanding of dark matter (which significantly impacts early structure formation), and through more accurate simulations of early galaxies (simulations of galaxy formation are exceedingly difficult to perform).
The second point is the most likely to change our understanding of early galaxy formation, aided by more and better observations of early galaxies.
I don't think that this sort of data will have much to say on the matter for some time yet. The main issue here is that doing the simulations of early structure formation correctly is computationally exceedingly difficult to get right, even if you know the underlying physics perfectly. We are forced to use a number of approximations to the underlying physics, and it's sometimes difficult to know just how much our approximations impact the final result of the simulation.AWA said:Sure, it's just that we are tightly constrained by the concordance model and by observation of high redshift galaxies when it comes to make simulations of early structure formation.
I guess pretty soon we'll have observational evidence to know if the model stands as it is or some corrections need to be made.
...especially as the authors themselves claim no such thing. From their paper, I'd say that they even don't see a real clash with the model they use for galaxy formation.For the time being, I would remain exceedingly skeptical of any claims of new physics that base their observational evidence on something as uncertain as galaxy formation simulations.
"Old and Distant Clusters" refer to groups of galaxies that are extremely old and located at great distances from Earth. These clusters are some of the oldest and most distant structures in the universe, with some dating back to the early stages of the universe's formation.
Scientists study "Old and Distant Clusters" through various methods such as using telescopes to observe and analyze the light emitted from these clusters, studying the movements of stars and galaxies within the cluster, and using computer simulations to model their formation and evolution.
"Old and Distant Clusters" provide valuable insights into the early stages of the universe's formation and evolution. By studying these clusters, scientists can better understand the processes that led to the formation of galaxies and other structures in the universe.
The age of "Old and Distant Clusters" can vary, but they are generally considered to be at least several billion years old. Some clusters have been estimated to be over 10 billion years old, dating back to the early stages of the universe's formation.
By studying the formation and evolution of "Old and Distant Clusters", scientists can gain insights into the fate of the universe. This research can provide clues about the rate of expansion of the universe, the distribution of dark matter and dark energy, and the potential for future structures to form.