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Fraser
2006-Mar-17, 01:51 AM
SUMMARY: An international team of astronomers have performed one of the most detailed surveys of the most distant galaxies. These galaxies are so far away, we see them as they looked when the Universe was less than half its current age. One of the big surprises of this survey; however, is how much these young galaxies match the structures we see in the current Universe. This means that galaxies probably evolved through collisions and mergers much earlier than previously believed.

View full article (http://www.universetoday.com/am/publish/aa_early_universe.html)
What do you think about this story? post your comments below.

antoniseb
2006-Mar-17, 02:07 PM
Didn't we see this story a couple months ago? Basically, it is looking at galaxies from seven billion years after the big bang, and saying they look similar to galaxies we see from 13 billion years after the big bang. It discuses it as a tool for looking at such galaxies much earlier, but the earlier galaxies aren't part of this study. This is an interesting study, but it is not casting doubt on any mainstream idea.

Jerry
2006-Mar-17, 05:28 PM
Didn't we see this story a couple months ago? Basically, it is looking at galaxies from seven billion years after the big bang, and saying they look similar to galaxies we see from 13 billion years after the big bang. It discusses it as a tool for looking at such galaxies much earlier, but the earlier galaxies aren't part of this study. This is an interesting study, but it is not casting doubt on any mainstream idea.
Bull pucky!



This means that galaxies probably evolved through collisions and mergers much earlier than previously believed...Up to now, distant galaxies were believed to be mainly interacting galaxies, with irregular and complex shapes.

This 'belief' is not a belief, this is a prediction of BB physics. Pushing the envelope back further means the prediction is wrong and must be revised. While it is true, revising the mainstream idea is a common practice, every time a prediction fails, the critical analysis process requires us to look at the roots, figure out why the prediction was made, and what parameter has to be modified, and then philisophically determine whether or not modifying the parameter makes sense.

True, other observations, such as XMS-Newton's catalogue of distant X-ray sources, and the radio background, have already pushed well beyond the visual light threshold, but these 'infant galaxies', as surveyed by Abraham and others, were first reported to be decidedly different from the local population.

This is very good, very productive analysis, and it does have major implications for currently accepted theories: There are many, many MS papers that study and report the evolution of galaxies between this early epoch and now. In stating that the earliest galaxies we can spectrographically analyse are as evolved as the current population, how do we interpret all these studies of galactic evolution?

ArgoNavis
2006-Mar-18, 11:53 PM
One of the big surprises of this survey; however, is how much these young galaxies match the structures we see in the current Universe. This means that galaxies probably evolved through collisions and mergers much earlier than previously believed.


The images accompanying this article would indicate that these galaxies are highly disturbed, which is not that frequent in the local Universe. Does anyone have a URL for the original paper? The way it has been written up sounds like nonsense.

Galaxies probably formed through a bottom up more than a top down process, as the early Universe was smaller, mergers and collisions were more frequent and galaxies grew by agggregation. This is still happening with the Milky Way, but on a less grander scale. This broad picture remains unchanged.