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View Full Version : Galaxies created just after 3Billion years of BB?



SiriMurthy
2004-Jan-08, 09:12 PM
I just saw this on CNN

http://www.cnn.com/2004/TECH/space/01/08/galaxies.find/index.html

Is it really possible to have galaxies created just 3 billion years after Big Bang? :-?

Anthrage
2004-Jan-08, 09:45 PM
Yes, it is. :)

Normandy6644
2004-Jan-08, 11:23 PM
We're talking about this in BABBling too, though it should probably be here. The fact is, if we see it, it's possible. It has long been questioned why galaxies appear so mature so early. It's a current hot topic that has several possible explanations, but not enough evidence to support any of them.

SiriMurthy
2004-Jan-09, 05:25 PM
We're talking about this in BABBling too, though it should probably be here. The fact is, if we see it, it's possible. It has long been questioned why galaxies appear so mature so early. It's a current hot topic that has several possible explanations, but not enough evidence to support any of them.

Yes, that's definitely possible. However, could it be that the Big Bang occurred much earlier than we thought?

The thing is that I am not sure whether a (well structured?) set of galaxies can form in 3B years.

Normandy6644
2004-Jan-09, 06:17 PM
I'm not sure about an earlier BB, though it may be possible. I can't remember exactly what evidence (aside from running the expansion backwards) there is for when it happened. But I think an earlier BB isn't really being considered as of yet.

dgruss23
2004-Jan-09, 06:28 PM
I think what you're really looking for is a solution that gives an older universe. This could be accomplished if you had a smaller value for the Hubble Constant. For any given Big Bang version, the smaller the current value of the Hubble constant, the older the universe is. If you have an older universe, then you have more time to form large structures.

This is why it is generally felt that these kinds of issues are not a Big Bang problem. If you can find the right values for the Big Bang's parameters and the right galaxy formation mechanisms, then theoretically you can fit these observations to the Big Bang.